Publications by authors named "Haihui Ye"

59 Publications

B-type allatostatin regulates immune response of hemocytes in mud crab Scylla paramamosain.

Dev Comp Immunol 2021 Feb 22;120:104050. Epub 2021 Feb 22.

College of Fisheries, Jimei University, Xiamen, 361021, China. Electronic address:

B-type allatostatins (AST-B) are neuropeptides that have important physiological roles in arthropods, they have also been identified in a number of crustacean species. Recent research on neuroendocrine-immune (NEI) regulatory system in invertebrates has exploded, it reveals that the NEI network plays an indispensable role in optimizing the immune response and maintaining homeostasis. Herein, mud crab Scylla paramamosain provides a primitive and ancient model to study crosstalk between the neuroendocrine and immune systems. In this study, qRT-PCR analysis showed that the nervous system was the main production site for Sp-AST-B mRNA in S. paramamosain, while its receptor gene (Sp-AST-BR) mRNA could be detected in all the analyzed tissues including hemocytes. This reveals that AST-B might act as a pleiotropic neuropeptide. In situ hybridization further confirmed that granular cells of hemocyte subpopulations express Sp-AST-BR. Time-course analysis revealed that bacteria-analog LPS or virus-analog Poly (I:C) challenge significantly induced Sp-AST-B expression in the thoracic ganglion, and the expression of Sp-AST-BR in hemocytes were also positively changed. Furthermore, mud crabs treated with a synthetic AST-B peptide significantly increased the mRNA levels of AST-BR, nuclear factor-κB (NF-κB) transcription factor (Dorsal and Relish), pro-inflammatory cytokine (IL-16) and immune-effector molecules, and also dramatically enhanced the nitric oxide (NO) production and phagocytic activity in hemocytes. Meanwhile dsRNA-mediated knockdown of Sp-AST-B remarkably suppressed the NO concentrations, phagocytic activity and the expression of immune related genes, resulting in markedly impaired ability of crabs to inhibit bacterial proliferation in vivo. Combined, these data demonstrate that AST-B induced innate immune in the mud crab.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.dci.2021.104050DOI Listing
February 2021

Insulin-like androgenic gland hormone 1 (IAG1) regulates sexual differentiation in a hermaphrodite shrimp through feedback to neuroendocrine factors.

Gen Comp Endocrinol 2021 Mar 25;303:113706. Epub 2020 Dec 25.

Fisheries Research Institute of Fujian, Xiamen 361013, People's Republic of China.

Insulin-like androgenic gland hormone (IAG) is regarded as a key sexual differentiation regulator in gonochoristic crustaceans. However, until now the knowledge concerning its functions in hermaphroditic crustaceans is scanty. Herein, we investigated the function of IAG (Lvit-IAG1) in peppermint shrimp Lysmata vittata, a species that possesses protandric simultaneous hermaphroditism (PSH) reproductive system, which is rare among crustaceans. Lvit-IAG1 was exclusively expressed in the androgenic gland. The qRT-PCR demonstrated that its mRNA expression level was relatively high at the functional male phase but decreased sharply in the subsequent euhermaphrodite phase. Both the short-term and long-term silencing experiments showed that Lvit-IAG1 negatively regulated both the gonad-inhibiting hormone (Lvit-GIH) and crustacean female sex hormone (Lvit-CFSH) expressions in the eyestalk ganglion. Besides, Lvit-IAG1 gene knockdown induced a retarded development of the appendices masculinae (AM) and male gonopores while suppressing the germ cells at the primary spermatocyte stage. Also, Lvit-IAG1 gene silencing hindered ovarian development. This in turn led to small vitellogenic oocytes and decreased expression of vitellogenin and vitellogenin receptor genes in hepatopancreas and ovarian region, respectively. Generally, this study's findings imply that Lvit-IAG1 modulated the male sexual differentiation in PSH species L. vittata, and exhibited negative feedback on Lvit-GIH and Lvit-CFSH genes expression in the species' eyestalk ganglion.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ygcen.2020.113706DOI Listing
March 2021

An effective digitization method for CTG paper report with binary background grids taken by smartphone.

Comput Methods Programs Biomed 2021 Mar 30;200:105872. Epub 2020 Nov 30.

Department of Obstetrics, Woman' s Hospital, School of Medicine, Zhejiang University, Hangzhou, 310006, China. Electronic address:

Background And Objective: Cardiotocography (CTG) is the most popular prenatal diagnostic examination, which includes continuous monitoring of foetal heart rate (FHR, bpm) and uterine contraction (UC, mmHg) signals. Compared with CTG paper reports, digitized reports have better storage, transmission and retrieval capabilities, in addition to being able to assess foetal health. However, most of the existing digitization methods extract signals from paper reports with colour background grids, and they cannot extract signals completely from paper reports with binary background grids, which are widely used in clinical CTG monitoring. Moreover, the existing digitization algorithms often neglect the image distortion caused by the imaging equipment.

Methods: To overcome the above drawbacks, a digitization method for CTG paper reports with binary background grids taken by smartphones is proposed in this paper. In the stage of removing the grid background, a region merger based on super-pixels and an improved binary line mask removal are designed. Then, signal extraction is performed separately according to the different states of the image column. Through a projection map used to synchronize the signal, the distortion effect of the mobile phone is removed.

Results: The experimental results show that the average correlation coefficient (ρ) between the recovery signal obtained by the proposed method and the reference signal is 0.9855±0.0108 for FHR and 0.9866 ± 0.1020 for UC, and the root mean square errors (RMSE) of FHR and UC processed by the proposed method are 1.0366 ± 0.4953 and 2.0355 ± 1.0246, and the mean absolute errors (MAE) of FHR and UC processed by the proposed method are 0.8735 ± 0.0684 and 1.4991 ± 0.2837, which are higher than those of the existing digitization methods. Compared with clinical signals, no significant difference is found in the feature of digitization CTG.

Conclusion: The proposed digitization method is a promising useful tool to realize the electronization of CTG signal.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cmpb.2020.105872DOI Listing
March 2021

Stimulatory roles of epidermal growth factor receptor (EGFR) in ovarian development of mud crab Scylla paramamosain.

Gen Comp Endocrinol 2020 12 17;299:113616. Epub 2020 Sep 17.

College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China. Electronic address:

The epidermal growth factor receptor (EGFR) is a pleiotropic glycoprotein which plays a role in regulating cell proliferation, migration and differentiation. However, to date little is known about its functions in crustaceans. In this study, we successfully identified SpEGFR from mud crab Scylla paramamosain. RT-PCR result showed that SpEGFR was widely distributed in all tested tissues and highly expressed in ovary. In situ hybridization revealed that SpEGFR mainly localized in oocyte perinuclear region with notably obvious signals. In vitro experiments showed that the expression of SpVgR and SpCyclin B in ovary explants from late vitellogenic stage crabs (summer) were significantly increased when treated with 1 nM human EGF (hEGF) for 1 h, while there was no obvious change towards SpEGFR. Interestingly, as for winter crab at the same vitellogenic stage, the expression of SpVgR and SpCyclin B in ovary explants did not show significant increase until treated with higher concentration of 10 nM hEGF and longer incubation time of 12 h. In addition, the hEGF-induced effect could be suppressed by pre-treated with EGFR inhibitor AG1478 and PD153035, respectively, which further indicated that EGF-EGFR pathway played a vital role in ovarian development in mud crab. In conclusion, SpEGFR might promote ovarian development by stimulating the expression of SpVgR and SpCyclin B under hEGF-induced treatment. The different physiological response to hEGF in the same vitellogenic stage crabs between summer and winter might be attributed to the changes in metabolism and physiological sensitivity.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ygcen.2020.113616DOI Listing
December 2020

Hepatopancreas immune response during molt cycle in the mud crab, Scylla paramamosain.

Sci Rep 2020 08 4;10(1):13102. Epub 2020 Aug 4.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, 361102, China.

Molt is a critical developmental process in crustaceans. Recent studies have shown that the hepatopancreas is an important source of innate immune molecules, yet hepatopancreatic patterns of gene expression during the molt cycle which may underlie changes in immune mechanism are unknown. In this study, we performed Illumina sequencing for the hepatopancreas of the mud crab, Scylla paramamosain during molt cycle (pre-molt stage, post-molt stage, and inter-molt stage). A total of 44.55 Gb high-quality reads were obtained from the normalized cDNA of hepatopancreas. A total of 70,591 transcripts were assembled; 55,167 unigenes were identified. Transcriptomic comparison revealed 948 differentially expressed genes (DEGs) in the hepatopancreas from the three molt stages. We found that genes associated with immune response patterns changed in expression during the molt cycle. Antimicrobial peptide genes, inflammatory response genes, Toll signaling pathway factors, the phenoloxidase system, antioxidant enzymes, metal-binding proteins and other immune related genes are significantly up-regulated at the post-molt stage and inter-molt stage compared with the pre-molt stage, respectively. These genes are either not expressed or are expressed at low levels at the pre-molt stage. To our knowledge, this is the first systematic transcriptome analysis of genes capable of mobilizing a hepatopancreas immune response during the molt cycle in crustaceans, and this study will contribute to a better understanding of the hepatopancreas immune system and mud crab prophylactic immune mechanisms at the post-molt stage.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-020-70139-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7403367PMC
August 2020

Transcriptional Inhibition of by Crustacean Female Sex Hormone in the Mud Crab, .

Int J Mol Sci 2020 Jul 26;21(15). Epub 2020 Jul 26.

College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China.

In crustaceans, the regulation of sex differentiation is mediated by insulin-like androgenic hormone (IAG) and crustacean female sex hormone (CFSH). CFSH is reported to inhibit IAG gene () expression in the mud crab , but the regulatory mechanism is not well understood. A 2674 bp 5' flanking contains many potential transcription factor binding sites. In this study, analysis of serially deleted 5' flanking and site-directed mutation (SDM) of transcription factor binding sites of the same gene showed that the promoter activity of reporter vectors with Sox-5-binding site, signal transducers and activators of transcription (STAT)-binding site and activator protein 1 (AP-1)-binding site were significantly higher than that of vectors without these regions, suggesting that they were involved in transcriptional regulation of expression. The expression analysis of these transcription factor showed that there was no difference in the level of mRNA in and in androgenic gland treated with recombinant CFSH, but expression of was significantly reduced, suggesting that CFSH regulates the expression of , inhibiting its function to regulate . Further experiment revealed that RNAi mediated gene knockdown reduced the expression of . These results suggested that CFSH regulates by inhibiting STAT. This is a pioneering finding on the transcriptional mechanism of gene in crustaceans.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms21155300DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7432471PMC
July 2020

Roles of gonad-inhibiting hormone in the protandric simultaneous hermaphrodite peppermint shrimp†.

Biol Reprod 2020 10;103(4):817-827

College of Ocean and Earth Sciences, Xiamen University, Xiamen, People's Republic of China.

To date, the molecular mechanisms of the unique gonadal development mode known as protandric simultaneous hermaphroditism (PSH) are unclear in crustaceans. In this study, cDNA of a gonad-inhibiting hormone (Lv-GIH1) was isolated from the PSH peppermint shrimp Lysmata vittata, and its expression was exclusively found in the eyestalk ganglion. Real-time quantitative polymerase chain reaction (qRT-PCR) revealed that the expression of Lv-GIH1 increased during gonadal development of the functional male stages but decreased significantly at subsequent simultaneous hermaphroditism stage. Further in vitro experiment showed that recombinant GIH1 protein (rGIH1) effectively inhibited Vg expression in the cultured hepatopancreas tissues while the short-term injection of GIH1-dsRNA resulted in reduced expression of Lv-GIH1 and upregulated expression of Vg in the hepatopancreas. Moreover, long-term rGIH1 injection led to significantly reduced expression of Lv-Vg, Lv-VgR, and Lv-CFSH1, subdued growth of oocytes, and feathery setae as a secondary sexual characteristic in females. Interestingly, while germ cells in testicular part were suppressed by rGIH1 injection, the expression of Lv-IAGs showed no significant difference; and long-term GIH1-dsRNA injection results were contrary to those of rGIH1 injection. Taken together, the results of this study indicate that Lv-GIH1 is involved in gonadal development and might also participate in controlling secondary sexual characteristic development in L. vittata by inhibiting Lv-CFSH1 expression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/biolre/ioaa111DOI Listing
October 2020

A Possible Role of Crustacean Cardioactive Peptide in Regulating Immune Response in Hepatopancreas of Mud Crab.

Front Immunol 2020 30;11:711. Epub 2020 Apr 30.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.

Crustacean cardioactive peptide (CCAP), a cyclic amidated non-apeptide, is widely found in arthropods. The functions of CCAP have been revealed to include regulation of heart rate, intestinal peristalsis, molting, and osmotic pressure. However, to date, there has not been any report on the possible involvement of CCAP in immunoregulation in crustaceans. In this study, a CCAP precursor (designated as -CCAP) was identified in the commercially important mud crab , which could be processed into four CCAP-associated peptides and one mature peptide (PFCNAFTGC-NH). Bioinformatics analysis indicated that -CCAP was highly conserved in crustaceans. RT-PCR results revealed that was expressed in nerve tissues and gonads, whereas the -CCAP receptor gene () was expressed in 12 tissues of , including hepatopancreas. hybridization further showed that an -positive signal is mainly localized in the F-cells of hepatopancreas. Moreover, the mRNA expression level of in the hepatopancreas was significantly up-regulated after lipopolysaccharide (LPS) or polyriboinosinic polyribocytidylic acid [Poly (I:C)] challenge. Meanwhile, the mRNA expression level of , nuclear transcription factor NF-κB homologs ( and ), member of mitogen-activated protein kinase (MAPK) signaling pathway (), pro-inflammatory cytokines factor ( and ), and antimicrobial peptide (, and ) in the hepatopancreas were all up-regulated after the administration of synthetic -CCAP mature peptide both and . The addition of synthetic -CCAP mature peptide also led to an increase in nitric oxide (NO) concentration and an improved bacterial clearance ability in the hepatopancreas culture medium. The present study suggested that -CCAP signaling system might be involved in the immune responses of by activating immune molecules on the hepatopancreas. Collectively, our findings shed new light on neuroendocrine-immune regulatory system in arthropods and could potentially provide a new strategy for disease prevention and control for mud crab aquaculture.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fimmu.2020.00711DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7204942PMC
March 2021

Identification of Peptides and Their GPCRs in the Peppermint Shrimp , a Protandric Simultaneous Hermaphrodite Species.

Front Endocrinol (Lausanne) 2020 30;11:226. Epub 2020 Apr 30.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.

Peptide hormones commonly binding with G-protein coupled receptors (GPCRs) achieve their function in reproduction. The peppermint shrimp popular in marine ornamental trade and is known to display protandric simultaneous hermaphrodite (PSH). Knowledge on reproductive biology of this commercial species is critical for resources management and aquaculture. This study employed Illumina sequencing and bioinformatics analysis to identify peptides and their candidate GPCRs from male phase (MP) and euhermaphrodite phase (EP) of . A total of 61 peptide and 40 peptide GPCR transcripts derive from 44 peptide families and 13 peptide GPCR families were identified, respectively. Among them, insulin-like androgenic gland hormone and crustacean female sex hormone have two unique mature peptides, respectively, and their transcripts showed higher expression levels in MP than EP, which suggest that these sex differentiation hormones might be involved in sexual characters than spermatogenesis or vitellogenesis. Overall, the first study on identification of peptides and their GPCRs in the genus extends our knowledge of peptidergic signaling in PSH species, and provides an important basis for development of aquaculture strategies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fendo.2020.00226DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7212414PMC
April 2020

B-type allatostatin modulates immune response in hepatopancreas of the mud crab Scylla paramamosain.

Dev Comp Immunol 2020 09 4;110:103725. Epub 2020 May 4.

College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China. Electronic address:

B-type allatostatin (AST-B) is a pleiotropic neuropeptide, widely found in arthropods. However, the information about its immune effect in crustaceans is unknown. In this study, we identified the nervous tissue as the main site for Sp-AST-B expression, while its receptor gene (Sp-AST-BR) is widely expressed in various tissues, including the hepatopancreas. This suggests the peptide's potential role in diverse physiological processes in the mud crab Scylla paramamosain. In situ hybridization revealed that Sp-AST-BR is mainly localized in the F-cell of hepatopancreas. Furthermore, we found a significant up-regulation of Sp-AST-BR transcripts in the hepatopancreas following exposure to lipopolysaccharide (LPS) or polyriboinosinic polyribocytidylic acid (Poly (I:C)). Results from in vitro and in vivo experiments revealed that treatment with a synthetic AST-B peptide mediated significant upregulation in expression of AST-BR, nuclear factor-κB (NF-κB) pathway components (Dorsal and Relish), pro-inflammatory cytokine (IL-16) and antimicrobial peptides (AMPs) in the hepatopancreas. In addition, AST-B treatment mediated significant elevation of nitric oxide (NO) production and enhanced the bacteriostasis capacity of the hepatopancreas tissue in vitro. Taken together, these findings reveal the existence of a basic neuroendocrine-immune (NEI) network in crabs, and indicate that AST-B could couple with its receptor to trigger downstream signaling pathways and induce immune responses in the hepatopancreas.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.dci.2020.103725DOI Listing
September 2020

DNA Methylation Inhibits the Expression of CFSH in Mud Crab.

Front Endocrinol (Lausanne) 2020 9;11:163. Epub 2020 Apr 9.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.

Crustacean female sex hormone (CFSH) is a key regulator of crustacean sex differentiation. The expression of in the mud crab showed a tissue-specific and gender-variant pattern. To explore the role of DNA methylation in expression, the 5'-flanking region of was cloned, and one CpG island containing 12 CpG sites was found. Results of sodium bisulfite sequencing and methylated DNA immunoprecipitation showed that CpG island methylation was stable in the eyestalk ganglion during ovarian development of the females, which was significantly lower than that in the muscle of the females and in the eyestalk ganglion of the males. Such results suggested that the involvement of DNA methylation in regulating expression followed an eyestalk ganglion-specific and gender-variant pattern. The analysis of CpG dinucleotide site methylation and activity of the site-directed mutation (SDM) reporter vector further demonstrated that methylation inhibited expression by blocking the binding of transcription factor Sp1. The finding suggested for the first time the involvement of CpG methylation in the regulation of expression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fendo.2020.00163DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7160318PMC
March 2021

Short neuropeptide F enhances the immune response in the hepatopancreas of mud crab (Scylla paramamosain).

Fish Shellfish Immunol 2020 Jun 6;101:244-251. Epub 2020 Apr 6.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, 361102, China. Electronic address:

Short neuropeptide F (sNPF), a highly conserved neuropeptide, displays pleiotropic functions on multiple aspects of physiological processes, such as feeding, metabolic stress, locomotion, circadian clock and reproduction. However, to date there has no any report on the possible immunoregulation of sNPF in crustaceans. In the present study, we found that the Sp-sNPF was mainly expressed in the nervous tissue in the mud crab Scylla paramamosain, while the sNPF receptor gene (Sp-sNPF-R) was expressed in a wide variety of tissues, including the hepatopancreas. In situ hybridization further showed that the Sp-sNPF-R positive signal mainly localized in the F-cells of the hepatopancreas. Moreover, the Sp-sNPF-R transcription could be significantly up-regulated after the challenge of bacteria-analog LPS or virus-analog Poly (I:C). Both in vitro and in vivo experiments showed that the synthetic sNPF peptide significantly increased the gene expressions of sNPF-R, nuclear factor-κB (NF-κB) signaling genes and antimicrobial peptides (AMPs) in the hepatopancreas. Simultaneously, the administration of sNPF peptide in vitro also increased the concentration of nitric oxide (NO) and the bacteriostasis of the culture medium of hepatopancreas. These results indicated that sNPF up-regulated hepatopancreas immune responses, which may bring new insight into the neuroendocrine-immune regulatory system in crustacean species, and could potentially provide a new strategy for disease prevention and control for mud crab aquaculture.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.fsi.2020.04.007DOI Listing
June 2020

Role of Oxytocin/Vasopressin-Like Peptide and Its Receptor in Vitellogenesis of Mud Crab.

Int J Mol Sci 2020 Mar 26;21(7). Epub 2020 Mar 26.

College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China.

Oxytocin (OT)/vasopressin (VP) signaling system is important to the regulation of metabolism, osmoregulation, social behaviours, learning, and memory, while the regulatory mechanism on ovarian development is still unclear in invertebrates. In this study, ot/vp-like and its receptor (ot/vpr-like) were identified in the mud crab Scylla paramamosain. ot/vp-like transcripts were mainly expressed in the nervous tissues, midgut, gill, hepatopancreas, and ovary, while ot/vpr-like were widespread in various tissues including the hepatopancreas, ovary, and hemocytes. In situ hybridisation revealed that ot/vp-like mRNA was mainly detected in 6-9 clusters in the cerebral ganglion, and oocytes and follicular cells in the ovary, while ot/vpr-like was found to localise in F-cells in the hepatopancreas and oocytes in the ovary. In vitro experiment showed that the mRNA expression level of vg in the hepatopancreas, vgr in the ovary, and 17β-estradiol (E) content in culture medium were significantly declined with the administration of synthetic OT/VP-like peptide. Besides, after the injection of OT/VP-like peptide, it led to the significantly reduced expression of vg in the hepatopancreas and subduced E content in the haemolymph in the crabs. In brief, OT/VP signaling system might inhibit vitellogenesis through neuroendocrine and autocrine/paracrine modes, which may be realised by inhibiting the release of E.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/ijms21072297DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7178253PMC
March 2020

Role of crustacean female sex hormone (CFSH) in sex differentiation in early juvenile mud crabs, Scylla paramamosain.

Gen Comp Endocrinol 2020 04 2;289:113383. Epub 2020 Jan 2.

College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China. Electronic address:

Recent studies have shown that crustacean female sex hormone (CFSH) is involved in the development of reproductive phenotype. In the present study, observation of sexually dimorphic traits revealed that gender could be distinguished from the third stage juveniles onwards in the mud crab, Scylla paramamosain. Sp-cfsh expression levels were analyzed in early juveniles. The results showed that, Sp-cfsh expression levels differed among individuals at post-molt of the first stage and second stage, and significantly different between the two sexes at post-molt of the third stage, which suggested that Sp-cfsh might participate in the sex differentiation in early juveniles. The expression of Sp-cfsh was examined during the molting cycle at the third stage juveniles, and the results showed that it was highest at the pre-molt stage. Based on the results, the expression of Sp-cfsh at pre-molt stage was further analyzed between the sexes from the third stage to the fifth stage, and it was found that the expression of Sp-cfsh was similar between two sexes at the third stage and the fourth stage; whereas at the fifth stage, when the gonopores occurred, the expression of Sp-cfsh significantly increased in females but decreased in males; suggesting that the expression of Sp-cfsh could influence the formation of gonopores. Finally, the role of Sp-cfsh in the reproductive phenotypes was confirmed through RNA interference knockdown. The combined results suggest that CFSH is involved in the regulation of sex differentiation of early juvenile in S. paramamosain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ygcen.2019.113383DOI Listing
April 2020

C-Type allatostatin and its putative receptor from the mud crab serve an inhibitory role in ovarian development.

J Exp Biol 2019 11 6;222(Pt 21). Epub 2019 Nov 6.

College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China

C-Type allatostatins are a family of peptides that characterized by a conserved unblocked PISCF motif at the C-terminus. In insects, it is well known that C-type allatostatin has a potent inhibitory effect on juvenile hormone biosynthesis by the corpora allata. C-Type allatostatin has been widely identified from crustacean species but little is known about its roles. Therefore, this study investigated the tissue distribution patterns of C-type allatostatin and its putative receptor in the mud crab , and further explored its potential effect on vitellogenesis. Firstly, cDNAs encoding C-type allatostatin () precursor and its putative receptor () were isolated. Subsequently, RT-PCR revealed that was mainly expressed in the nervous tissue, middle gut and heart, whereas had extensive expression in all tissues tested except the eyestalk ganglion and hepatopancreas. In addition, hybridization in the cerebral ganglion showed that was localized in clusters 6 and 8 of the protocerebrum, clusters 9, 10 and 11 of the deutocerebrum, and clusters 14 and 15 of the tritocerebrum. Whole-mount immunofluorescence revealed a similar distribution pattern. Synthetic AST-C had no effect on the abundance of vitellogenin () in the hepatopancreas and ovary but significantly reduced the expression of its receptor () in the ovary in a dose-dependent manner Furthermore, expression, vitellin content and oocyte diameter in the ovary were reduced 16 days after the first injection of -AST-C. Finally, hybridization showed that transcript was specifically localized in the oocytes, which further indicated that the oocytes are the target cells for AST-C. In conclusion, our results suggested that the AST-C signaling system is involved in the regulation of ovarian development, possibly by directly inhibiting the uptake of yolk by oocytes and obstructing oocyte growth.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1242/jeb.207985DOI Listing
November 2019

Source of hemolymph microbiota and their roles in the immune system of mud crab.

Dev Comp Immunol 2020 01 17;102:103470. Epub 2019 Aug 17.

Guangdong Provincial Key Laboratory of Marine Biotechnology & Marine Biology Institute, Shantou University, Shantou, China. Electronic address:

Special innate immune mechanisms against pathogens are developed in marine invertebrates such as mud crab, which is also an economically important aquaculture species in many coastal countries. Hemolymph is a critical site in host immune response, but its source of microorganisms is less known. In this study, we provided a detailed investigation of the microorganisms inhabiting various body sites of healthy mud crabs, including hemolymph, midgut, gill, subcuticular epidermis and hepatopancreas. By using fluorescence microscopy and high-throughput sequencing of the bacterial 16S rRNA genes, various abundances and kinds of microorganisms were observed in the healthy mud crabs, of which some are potential pathogens to mud crab and human. The SourceTracker analysis and oral injection experiment confirm the hypothesis that hemolymph microorganisms are derived from the digestive systems of invertebrates with open circulatory systems, indicating that these microorganisms play vital roles in crab immune response. Moreover, physiological differences (gut length), behavioral characteristics (foraging behavior), diet preferences (herbivory), and/or sex hormones (testosterone) possibly determine the unique features of the crab-associated microbiota for both sexes. These findings also contribute to the development of appropriate microbial immunoenhancers, which has potential applications for improving quality and yield during crab aquaculture.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.dci.2019.103470DOI Listing
January 2020

Role of neuroparsin 1 in vitellogenesis in the mud crab, Scylla paramamosain.

Gen Comp Endocrinol 2020 01 17;285:113248. Epub 2019 Aug 17.

College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China. Electronic address:

Neuroparsin (NP) is an important neuropeptide in invertebrates. It is well-known that NP displays multiple biological activities, including antidiuretic and inhibition of vitellogenesis in insects. However, the information about its effect in crustaceans is scarce. In this study, the sequence of Sp-NP1 was selected from the transcriptome database from the mud crab, Scylla paramamosain. Sequence analyses indicate that the Sp-NP1 amino acid (AA) sequences consist of a 27 AA signal peptide and a 74 AA mature peptide, which contains 12 cysteine residues. qRT-PCR analysis has revealed that the expressions of Sp-NP1 gene are high in the nervous tissues and extremely low in the ovary and hepatopancreas. In situ hybridization has shown that the positive signals are localized in cell cluster 6 of protocerebrum and cell clusters 10 and 11 of deutocerebrum. The presence of Sp-NP1 in the haemolymph has been detected in S. paramamosain through western blot, which indicates that Sp-NP1 serves as an endocrine factor in the regulation of physiological activities. In vitro experiments have further shown that the mRNA level of vitellogenin in the hepatopancreas notably decreases following administration of recombinant Sp-NP1, while the mRNA level of vitellogenin receptor and cyclin B in the ovary shows no significant differences. Collectively, Sp-NP1 possibly can inhibit the production of vitellogenin in the hepatopancreas and has no direct effect on the ovary in S. paramamosain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ygcen.2019.113248DOI Listing
January 2020

Profiles of calreticulin and Ca2+ concentration under low temperature and salinity stress in the mud crab, Scylla paramamosain.

PLoS One 2019 25;14(7):e0220405. Epub 2019 Jul 25.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.

Calreticulin (CRT) is an important molecular chaperon crucial to survival of organisms under adverse conditions. In this study, the potential roles of CRT in the mud crab, Scylla paramamosain, were investigated. Firstly, SpCRT gene expression was detected in various tissues of S. paramamosain with the highest expression found in the hepatopancreas. To evaluate potential role of SpCRT in cold adaption, sub-adult crabs were subjected to temperatures of 10, 15, 20 and 25°C and the profiles of SpCRT gene were determined in the hepatopancreas, chela muscle and gills. The results showed that the expressions of SpCRT mRNA in these tissues were significantly higher for those crabs exposed to low temperatures of 10 and 15°C as compared to those exposed to the higher temperatures, indicating SpCRT was involved in cold adaptation-probably through facilitating protein folding. When low temperature 10°C or 15°C was further combined with high and low salinity stress, the expression of SpCRT mRNA at low salinity (10 ppt) was in most cases significantly higher than that at high salinity (35 ppt), suggesting that under low temperatures, low salinity may represents a more stressful condition to the crab than high salinity. It was also shown that when crabs challenged by 10°C, Ca2+ concentration increased rapidly in the hepatopancreas and an in vitro experiment further showed that the expression of SpCRT mRNA increased concurrently with added Ca2+ concentration; these results together imply that Ca2+ probably plays a major role in low temperature signaling, which induces expression of genes related to cold adaption, such as CRT.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0220405PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6657906PMC
March 2020

Serotonergic Mechanisms of Oocyte Germinal Vesicle Breakdown in the Mud Crab, .

Front Physiol 2019 19;10:797. Epub 2019 Jun 19.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.

The mechanism of serotonin (5-HT)-induced oocyte germinal vesicle breakdown (GVBD) in the mud crab, , was investigated in this study. Histological staining showed that there were two meiotic arrests in oocyte, appearing at prophase I and metaphase I. This result indicated that meiosis I arrest at prophase I in was similar to that of vertebrates, but meiosis II arrest at metaphase I was different from that of vertebrates. Resumption of oocytes arrest at meiosis prophase I could be induced by 5-HT rapidly within 5 min in . We obtained the sequence of the 5-HT receptor type 1A ( ) from the NCBI database, and found that was expressed in oocytes and follicle cells. In addition, we found that an agonist 8-OH-DPAT which binds induced GVBD and an antagonist WAY100635 which inhibited 5-HT induced GVBD in . This result showed that mediated the regulation of oocyte GVBD by 5-HT. To explore the functional mechanism of 5-HT in inducing oocyte GVBD, forskolin, a cAMP agonist was used. Results showed that, forskolin significantly blocked 5-HT-induced GVBD, and there was a negative correlation between GVBD rate and cAMP level. Our data indicate that there are two meiotic arrests in , and the resumption of prophase I arrest can be induced by 5-HT, which binds to , and this process is mediated by cAMP, which acts as negative regulator via cAMP signaling pathway.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fphys.2019.00797DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6593242PMC
June 2019

Salinity can change the lipid composition of adult Chinese mitten crab after long-term salinity adaptation.

PLoS One 2019 3;14(7):e0219260. Epub 2019 Jul 3.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.

The Chinese mitten crab (Eriocheir sinensis) is an euryhaline crustacean, whose adults migrate downstream to estuaries for reproduction. Lipids are believed to be involved in salinity adaptation during migration. This study investigated the effects of different salinities (0, 6, 12, and 18‰) on the total lipids, neutral lipids, and polar lipids contents, and fatty acid profiles in the gonads, hepatopancreas, and muscles of adult E. sinensis after 40 days of salinity adaptation. The results showed that the males and females from 12‰ treatment had the highest contents of total lipids and neutral lipids in their hepatopancreas and total lipids in the muscles. Notably, salinity had a greater effect on the fatty acid profiles in the hepatopancreas compared to that in the gonads and muscles. The male hepatopancreas treated with 18‰ salinity had the highest percentage of total n-6 polyunsaturated fatty acid (∑n-6PUFA) in both neutral lipids and polar lipids, while the percentage of total n-3 polyunsaturated fatty acid (∑n-3PUFA) in neutral lipids and polar lipids decreased significantly with increasing salinity in males. In females, the 0‰ treatment had the highest percentages of total saturated fatty acids in neutral lipids and polar lipids in the hepatopancreas, while the highest ∑n-3PUFA and ∑n-6PUFA in neutral lipids and polar lipids were detected in the 12‰ treatment group. In conclusion, brackish water could promote the accumulations of total lipids and neutral lipids in the hepatopancreas and change the fatty acid profiles of adult E. sinensis, particularly in the hepatopancreas after long-term salinity adaptation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0219260PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6608974PMC
February 2020

Ontogenetic development of gonads and external sexual characters of the protandric simultaneous hermaphrodite peppermint shrimp, Lysmata vittata (Caridea: Hippolytidae).

PLoS One 2019 19;14(4):e0215406. Epub 2019 Apr 19.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.

The peppermint shrimp Lysmata vittata (Caridea: Hippolytidae) is a marine caridean shrimp popular in marine aquarium trade. The species is known to display the sexual system of protandric simultaneous hermaphrodite. In this study, based on captive bred specimens, the complete ontogenetic gonad development of L. vittata was studied both morphologically and histologically, from newly settled juveniles until they reached euhermaphrodite phase. It was found that in all specimens examined (carapace length: 1.8-8.5 mm), including the newly settled juveniles, possessed ovotestes, which comprised of an anterior ovarian and a posterior testicular part. Based on both morphological (e.g., size, color and shape) and histological features (e.g., oogenesis and spermatogenesis), four gonadal development stages were defined and described for L. vittata. From Stage I to III, the testicular part of the gonad became gradually mature but the ovarian part was still immature, which is defined as the male phase. At the male phase, cincinulli (5-8 hooks) presented at the tips of the appendix interna on the first pair of pleopods while appendices masculinae (AM), in a form of a stick structure with spines, presented at the inner edge of the appendix interna (AI) on the second pair of pleopods. At Stage IV, both the testicular part and the ovarian part were mature and hence is defined as euhermaphrodite phase. At the euhermaphrodite phase, most individuals lacked cincinulli and appendices masculinae on the first and second pair of pleopods respectively. This is the first time that complete ontogenetic gonadal and external sexual character development have been described and staged for a species from the genus Lysmata from newly settled juveniles to euhermaphrodite phase.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0215406PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6474713PMC
January 2020

[Intelligent fetal state assessment based on genetic algorithm and least square support vector machine].

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 2019 Feb;36(1):131-139

The Women's Hospital School of Medicine Zhejiang University, Hangzhou 310006, P.R.China.

Cardiotocography (CTG) is a commonly used technique of electronic fetal monitoring (EFM) for evaluating fetal well-being, which has the disadvantage of lower diagnostic rate caused by subjective factors. To reduce the rate of misdiagnosis and assist obstetricians in making accurate medical decisions, this paper proposed an intelligent assessment approach for analyzing fetal state based on fetal heart rate (FHR) signals. First, the FHR signals from the public database of the Czech Technical University-University Hospital in Brno (CTU-UHB) was preprocessed, and the comprehensive features were extracted. Then the optimal feature subset based on the -nearest neighbor (KNN) genetic algorithm (GA) was selected. At last the classification using least square support vector machine (LS-SVM) was executed. The experimental results showed that the classification of fetal state achieved better performance using the proposed method in this paper: the accuracy is 91%, sensitivity is 89%, specificity is 94%, quality index is 92%, and area under the receiver operating characteristic curve is 92%, which can assist clinicians in assessing fetal state effectively.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7507/1001-5515.201804046DOI Listing
February 2019

A novel crustacean hyperglycemic hormone (CHH) from the mud crab Scylla paramamosain regulating carbohydrate metabolism.

Comp Biochem Physiol A Mol Integr Physiol 2019 05 26;231:49-55. Epub 2019 Jan 26.

College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China. Electronic address:

Crustacean hyperglycemic hormone (CHH) plays a crucial role in regulating carbohydrate metabolism in crustaceans. In this study, a new cDNA encoding type I CHH peptide, termed Sp-CHH3, was isolated from the mud crab Scylla paramamosain and its potential functions were investigated. The full length cDNA of Sp-CHH3 was identified as encoding a 127-aa precursor composed of a 27-aa signal peptide, a 23-aa CHH precursor-related peptide and a 75-aa mature peptide with a typical motif of CHH. Phylogenic analysis suggested that, Sp-CHH3 is a previously unreported CHH from S. paramamosain. Tissue distribution analysis showed that Sp-CHH3 was mainly expressed in the eyestalk ganglia, thoracic ganglia, stomach and the ovary. A RNA interference experiments showed that after injection of Sp-CHH3-targeted dsRNA, both the level of Sp-CHH3 expression in the eyestalk ganglia and hemolymph glucose level decreased significantly. A further short-term starvation experiments demonstrated that, the level of Sp-CHH3 detected in the eyestalk ganglia was significantly up-regulated at the 12th h of starvation, it then fell back at the 24th h of starvation and subsequently remained relative stability between the 24th to 96th h of starvation. The hemolymph glucose level decreased significantly (P < .05) at each sampling time during the 96 h starvation duration when compared to that of 0 h (prior to starvation) and the overall trend was largely correlated with the level of Sp-CHH3 expression in the eyestalk ganglia. In summary, the results suggest that Sp-CHH3 plays a functional role in regulating carbohydrate metabolism in S. paramamosain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cbpa.2019.01.015DOI Listing
May 2019

Identifying neuropeptide GPCRs in the mud crab, Scylla paramamosain, by combinatorial bioinformatics analysis.

Gen Comp Endocrinol 2018 12 3;269:122-130. Epub 2018 Sep 3.

College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen 361102, Fujian Province, China. Electronic address:

Neuropeptides, ubiquitous signaling molecules, commonly achieve their signaling function via interaction with cell membrane-spanning G-protein coupled receptors (GPCRs). In recent years, in the midst of the rapid development of next-generation sequencing technology, the amount of available information on encoded neuropeptides and their GPCRs sequences have increased dramatically. The repertoire of neuropeptides has been determined in many crustaceans, including the commercially important mud crab, Scylla paramamosain; however, determination of GPCRs is known to be more difficult and usually requires in vitro binding tests. In this study, we adopted a combinatorial bioinformatics analysis to identify S. paramamosain neuropeptide GPCRs. A total of 65 assembled GPCR sequences were collected from the transcriptome database. Subsequently these GPCRs were identified by comparison to known neuropeptide GPCRs based on the sequence-similarity-based clustering and phylogenetic analysis, which showed that many of them are closely related to insect GPCR families. Of these GPCRs, most of them were detected in various tissues of the mud crab and some of them showed differential expression by gender, suggesting they are involved in different physiological processes, such as sex differentiation. By employing ligand-receptor binding tests, we demonstrated that the predicted crustacean cardioactive peptide (CCAP) receptor was activated by CCAP peptide in a dose-dependent manner. This is the first CCAP receptor that has been functionally defined in crustaceans. In summary, the present study shortlists candidate neuropeptide GPCRs for ligand-receptor binding tests, and provides information for subsequent future research on the neuropeptide/GPCR signaling pathway in S. paramamosain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ygcen.2018.09.002DOI Listing
December 2018

Crustacean Female Sex Hormone From the Mud Crab Is Highly Expressed in Prepubertal Males and Inhibits the Development of Androgenic Gland.

Front Physiol 2018 17;9:924. Epub 2018 Jul 17.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.

Recently, the crustacean female sex hormone (CFSH), which is considered a female-specific hormone, has been shown to play a crucial role in female phenotypes in crustaceans. In this study, two transcripts ( and ) encoding the same CFSH precursor were cloned from the mud crab . Homology and phylogenetic analysis showed that CFSHs were homologous to interleukin-17 and highly conserved among brachyuran crabs. PCR analysis revealed that was expressed exclusively in the eyestalk ganglion of both prepubertal males and females, and surprisingly, the abundance of transcripts detected in the males were not significantly different from that of the females ( > 0.05). In addition, mRNA hybridization showed that was localized in the X-organ of the male eyestalk ganglion. During the development of the androgenic gland (AG), the level of mRNA in AG remained at low levels from stages I to II (early stage) but had a significant increase at stage III (mature stage). In contrast, the level of transcripts in the eyestalk ganglion was high in the early stage but extremely low in the mature stage. To investigate the potential function of CFSH in male , the recombinant protein (∼20 kDa) was expressed in and was subsequently added to AG explants . It was demonstrated that recombinant protein significantly reduced the expression of in the AG explants at a concentration of 10 M ( 0.05). In conclusion, our study provides the first piece of evidence that shows CFSH from the eyestalk ganglion acts as a negative regulator inhibiting the development of AG in crustaceans.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fphys.2018.00924DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6056722PMC
July 2018

Inhibitory Role of the Mud Crab Short Neuropeptide F in Vitellogenesis and Oocyte Maturation via Autocrine/Paracrine Signaling.

Front Endocrinol (Lausanne) 2018 13;9:390. Epub 2018 Jul 13.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.

Neuropeptides, in addition to their classical role in the nervous system, act on intraovarian factors to regulate reproductive functions in vertebrates. However, this function of neuropeptides has not been characterized in crustaceans. Short neuropeptide F (sNPF), a highly conserved invertebrate neuropeptide, has been reported to be involved in feeding, metabolism, and in differentiation processes including reproduction. Although sNPF and its receptor (sNPFR) have been detected in the ovary in different species, ovarian colocalization of sNPF/sNPFR has not been investigated. In this study, we identified (mud crab) sNPF (-sNPF) as an endogenous ligand for the orphan G protein-coupled receptor NPY2R in mammalian cell line HEK293T. We designated this receptor as . RNA hybridization in pre-vitellogenic ovary and reverse transcription-PCR on isolated denuded oocytes and follicle layers showed that was exclusively localized to the follicle cells, whereas was detected in both follicle cells and oocytes. We also found that -sNPF partly suppressed spontaneous maturation of denuded oocytes and caused intracellular cAMP accumulation and Ca mobilization. Moreover, injection of synthetic -sNPF peptides inhibited the expression of vitellogenin and vitellogenin receptor genes . These combined results suggest for the first time that -sNPF may have inhibitory functions in vitellogenesis and oocyte maturation possibly via the autocrine/paracrine pathway.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fendo.2018.00390DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6053504PMC
July 2018

Voltage-dependent calcium channels in the neurosecretory cells of cerebral ganglia of the mud crab, Scylla paramamosain.

Neuroreport 2018 09;29(13):1068-1074

Department of Marine Biological Science & Technology, College of Ocean and Earth Sciences, Xiamen University.

Voltage-dependent calcium channels (VDCCs) play a critical role in stimulus-secretion coupling in neurosecretory cells (NSCs). The crustacean cerebral ganglion plays a crucial role in neuromodulation and controls neuropeptide release. The present study used patch-clamp and Illumina sequencing techniques to investigate the potential features of VDCC in the cerebral ganglia of the mud crab (Scylla paramamosain). The electrophysiological characteristics of VDCC were analyzed in three types of NSCs with a patch clamp. The thresholds for activation of Ca channel current recorded from all the three types of NSCs were all above -40 mV, with peak amplitudes occurring around 0 mV. Therefore, it was concluded that the currents recorded in NSCs were mediated by high-voltage-activated Ca channels. Ca channel current densities in I type NSCs were significantly lower than those in II and III type NSCs. Four VDCC subunits derived from three transcripts were predicted from a transcriptome database of the cerebral ganglia. Among these transcripts, Cavα1, Cavβ, and Cavα2/δ were predicted to encode 1674, 554, and 776 amino acids, respectively, and they shared conservative domains with VDCC subunits in other species. Overall, these findings provide an important basis for further studies on the neuroendocrine mechanisms in crustaceans.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/WNR.0000000000001074DOI Listing
September 2018

Does the bone morphogenetic protein 7 inhibit oocyte maturation by autocrine/paracrine in mud crab?

Gen Comp Endocrinol 2018 09 7;266:119-125. Epub 2018 May 7.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, China; Fujian Collaborative Innovation Center for Exploitation and Utilization of Marine Biological Resources, Xiamen, China. Electronic address:

A bone morphogenetic protein ligand (BMP7) and its two receptors (BMPRIB and BMPRII) were recently cloned and characterized in the mud crab, Scylla paramamosain. However specific functions of BMP7 and the mechanistic pathways regulating its function are largely unidentified. In the present study, we separated oocytes and follicle cells from the ovarian explants of S. paramamosain. Subsequent analysis using semi-quantitative PCR demonstrated that the mRNA of Sp-BMP7 was exclusively expressed in follicle cells while Sp-BMPRs were expressed in both oocytes and follicle cells. In vitro experiments further showed that the mRNA and protein levels of Cyclin B increased but Sp-BMP7 declined in 17α, 20β-Dihydroxyprogesterone (DHP)-induced oocytes. Furthermore, the inhibitory effects of Sp-BMP7 were not affected by the elimination of the contact/gap junction-mediated communication between oocytes and follicle cells. Our data indicate that BMP7 may play a role in the suppression of DHP-induced oocyte maturation by affecting autocrine/paracrine pathways in S. paramamosain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ygcen.2018.05.004DOI Listing
September 2018

Physiological Responses and Ovarian Development of Female Chinese Mitten Crab Subjected to Different Salinity Conditions.

Front Physiol 2017 4;8:1072. Epub 2018 Jan 4.

Department of Marine Biology and Technology, College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.

Salinity plays a key role affecting ovarian development, osmoregulation and metabolism of female Chinese mitten crab, during reproductive migration. In this study, female after their puberty molt were subjected to four salinities of 0, 6, 12, and 18‰ for 40 days to investigate the salinity effects on their ovarian development as well as a range of important physiological parameters. Elevated salinity accelerated the ovarian development with ovigerous crabs found at salinity treatments of 12 and 18‰ despite no copulation had occurred. Meanwhile the survival rate of female crabs showed a decreasing trend with increasing salinity. Higher salinity also led to increased hemolymph Na, K, Ca, Cl, and Mg concentrations. The 6‰ treatment had the highest contents of hemolymph total and major free amino acids while the Na/K -ATPase activity in the posterior gills was the lowest among treatments. Total n-3 polyunsaturated fatty acids (∑n-3PUFA) and n-3/n-6 PUFA ratio in the anterior gills showed a decreasing trend with salinity while 18‰ had the highest ∑PUFA and ∑n-6PUFA. The ∑n-3PUFA content and n-3/n-6 PUFA ratio of the posterior gills showed a fluctuating pattern and the highest value was detected at 0‰, while an increasing trend was found for the ∑n-6PUFA with increasing salinity. The hemolymph glucose showed a decreasing trend with increasing salinity and the highest total cholesterol in hemolymph was detected at 12‰. The 18‰ treatment had the highest levels of hemolymph γ-glutamyltransferase, alkaline phosphatase and acid phosphatase, as well as glucose, urea and acid phosphatase in hepatopancreas while the highest hemolymph superoxide dismutase and malondialdehyde were detected at 0‰. Overall, the results showed that salinity increase from freshwater to brackish conditions led to lower metabolism, accelerated ovarian development, and the appearance of ovigerous crabs without copulation in female post puberty molt.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fphys.2017.01072DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5761441PMC
January 2018

Transcriptome profiling of claw muscle of the mud crab (Scylla paramamosain) at different fattening stages.

PLoS One 2017 15;12(11):e0188067. Epub 2017 Nov 15.

College of Ocean and Earth Sciences, Xiamen University, Xiamen, China.

In crustaceans, muscle growth and development is complicated, and to date substantial knowledge gaps exist. In this study, the claw muscle, hepatopancreas and nervous tissue of the mud crab (Scylla paramamosain) were collected at three fattening stages for sequence by the Illumina sequencing. A total of 127.87 Gb clean data with no less than 3.94 Gb generated for each sample and the cycleQ30 percentages were more than 86.13% for all samples. De Bruijn assembly of these clean data produced 94,853 unigenes, thereinto, 50,059 unigenes were found in claw muscle. A total of 121 differentially expressed genes (DEGs) were revealed in claw muscle from the three fattening stages with a Padj value < 0.01, including 63 genes with annotation. Functional annotation and enrichment analysis showed that the DEGs clusters represented the predominant gene catalog with roles in biochemical processes (glycolysis, phosphorylation and regulation of transcription), molecular function (ATP binding, 6-phosphofructokinase activity, and sequence-specific DNA binding) and cellular component (6-phosphofructokinase complex, plasma membrane, and integral component of membrane). qRT-PCR was employed to further validate certain DEGs. Single nucleotide polymorphism (SNP) analysis obtained 159,322, 125,963 and 166,279 potential SNPs from the muscle transcriptome at stage B, stage C and stage D, respectively. In addition, there were sixteen neuropeptide transcripts being predicted in the claw muscle. The present study provides a comprehensive transcriptome of claw muscle of S. paramamosain during fattening, providing a basis for screening the functional genes that may affect muscle growth of S. paramamosain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0188067PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5687733PMC
December 2017