Publications by authors named "Baolong Bao"

39 Publications

Isolation of prolactin gene and its differential expression during metamorphosis involving eye migration of Japanese flounder Paralichthys olivaceus.

Gene 2021 May 23;780:145522. Epub 2021 Feb 23.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, Shanghai 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai 201306, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China. Electronic address:

Eye migration during flatfish metamorphosis is driven by asymmetrical cell proliferation. To figure out Prolactin (PRL) function in this process, the full-length cDNA of prl was cloned from Japanese flounder (Paralichthys olivaceus) in our study. The deduced PRL protein shares highly conserved sequence with other teleosts, but has several amino acids loss compared with higher vertebrates, including amphibians, reptiles, avian and mammals. Spatio-temporal expression of prl gene displayed its extensive expression in the early development stages, while the limited expression of prl was observed in the pituitary, brain, and intestine of adult fish. In situ hybridization showed the asymmetrical distribution patterns of prl gene around the eyes during metamorphosis, which was coincident with the cell proliferation signals. Colchicine inhibited cell proliferation and reduced the prl gene expression, which indicates that PRL was involved in cell proliferation in the suborbital area of the migrating eye. The treatment of methimazole and 9-cis-retinoic acid respectively led to a reduction in the number of proliferating cells and the downregulation of prl expression, suggesting PRL was regulated by thyroid hormone signaling pathway and retinoic acid related signaling pathways. The results gave us a basic understanding of PRL function during flatfish metamorphosis.
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http://dx.doi.org/10.1016/j.gene.2021.145522DOI Listing
May 2021

Extracellular vesicles piwi-interacting RNAs from skin mucus for identification of infected Cynoglossus semilaevis with Vibrio harveyi.

Fish Shellfish Immunol 2021 Apr 6;111:170-178. Epub 2021 Feb 6.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, Shanghai Ocean University, Shanghai, 201306, China; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, 201306, China. Electronic address:

Extracellular vesicles play a regulatory role in intracellular and intercellular transmission through a variety of biological information molecules, including mRNA, small RNAs and proteins. piRNAs are one kind of regulatory small RNAs in the vesicles at the post transcriptional level. Hereby, we isolated the extracellular vesicles from skin mucus and screened the piRNA profiles of these vesicles, aiming at developing biomarkers related to bacterial infections in Cynoglossus semilaevis. The different profilings of piRNAs in mucous extracellular vesicles of C. semilaevis were compared through small RNA sequencing, between fish infected with Vibrio harveyi and healthy ones. The number of clean reads on the alignment of exosome sick (ES) group was 105, 345 and that of exosome control (EC) group was 455, 144. GO and KEGG pathway enrichment analysis showed that most of the target genes were involved in cellular process, response to stimulus, biological regulation, immune system process and signal transduction, signal molecular and interaction, transport and catabolism. The 45 final candidate piRNAs related to immunity or infectious diseases included 20 piRNAs with high expression in the ES group and 25 piRNAs with a low expression in the ES group. After verification by qRT-PCR, there was significant difference of five piRNAs expression level between infected fish and healthy fish, in line with the sequencing. The expression level of piR-mmu-16401212, piR-mmu-26829319 and piR-gga-244092 in infected fish were significantly lower than that of control group, while piR-gga-71717 and piR-gga-99034 were higher, which implying that these piRNAs in mucous extracellular vesicles can be used to identify diseased fish from normal ones. This work supplied a novel class of biomarker for infection diagnosis in fish, and it will be benefit for screening disease resistant breeding of C. semilaevis.
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http://dx.doi.org/10.1016/j.fsi.2021.02.001DOI Listing
April 2021

Single-nucleotide polymorphisms responsible for pseudo-albinism and hypermelanosis in Japanese flounder (Paralichthys olivaceus) and reveal two genes related to malpigmentation.

Fish Physiol Biochem 2021 Apr 6;47(2):339-350. Epub 2021 Jan 6.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Shanghai, China.

Paralichthys olivaceus is the kind of cold-water benthic marine fish. In the early stages of development, the symmetrical juveniles transform into an asymmetrical body shape through metamorphosis for adapting benthic life. After that, one side of the fish body is attached to the ground, and the eyes turn to the opposite side which is called ocular side. The body color also appears asymmetry. The skin on the ocular side is dark brown, and the skin on the blind side is white without pigmentation. Pseudo-albinism and hypermelanosis have been considered distinct body color disorders in flatfish. Pseudo-albinism and hypermelanosis in Paralichthys olivaceus are due to abnormal or uneven pigment distribution, due to the interaction of hereditary and environmental factors, rather than a single-nucleotide mutation of a specific gene. Here, we report three single-nucleotide polymorphisms (SNPs) responsible for both pseudo-albinism and hypermelanosis, which are located on two body color-related genes involved in melanogenesis-related pathways. c.2440C>A (P. V605I) and c.2271-96T>C are located on the Inositol 1,4,5-trisphosphate receptor type 2-like (ITPR2) (Gene ID: 109624047), they are located in exon 16 and the non-coding region, respectively, and c.2406C>A (P.H798N) is located in exon 13 of the adenylate cyclase type 6-like (AC6) gene(Gene ID: 109630770). ITPR2 and AC6 expression, which both participate in the thyroid hormone synthesis pathway associated with pseudo-albinism and hypermelanosis in P. olivaceus, were also investigated using qRT-PCR. In hypermelanotic fish, there were relatively higher levels of expression in ITPR2 and AC6 mRNA of hyper-pigmented skin of blind side than that of non-pigmented skin on the blind side and pigmented skin on the ocular side, while in pseudo-albino fish, expression level of ITPR2 and AC6 mRNA in pigmented skin of ocular side was significantly higher than that in non-pigmented skin both ocular and blind side. The results indicated that the expression of the two genes in abnormal parts of body color is positively correlated with pigmentation, suggesting that the influence of abnormal expression of two genes on the pigmentation in abnormal parts of body color deserves further study.
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http://dx.doi.org/10.1007/s10695-020-00916-3DOI Listing
April 2021

CRISPR/Cas9-induced nos2b mutant zebrafish display behavioral abnormalities.

Genes Brain Behav 2020 Nov 16:e12716. Epub 2020 Nov 16.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China.

The immunomodulatory function of nitric oxide synthase (NOS2) has been extensively studied. However, some behavioral abnormalities caused by its mutations have been found in a few rodent studies, of which the molecular mechanism remains elusive. In this research, we generated nos2b gene knockout zebrafish (nos2b ) using CRISPR/Cas9 approach and investigated their behavioral and molecular changes by doing a series of behavioral detections, morphological measurements, and molecular analyses. We found that, compared with nos2b zebrafish, nos2b zebrafish exhibited enhanced motor activity; additionally, nos2b zebrafish were characterized by smaller brain size, abnormal structure of optic tectum, reduced mRNA level of presynaptic synaptophysin and postsynaptic homer1, and altered response to sodium nitroprusside/methylphenidate hydrochloride treatment. These findings will likely contribute to future studies of behavioral regulation.
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http://dx.doi.org/10.1111/gbb.12716DOI Listing
November 2020

Detecting Cynoglossus semilaevis infected with Vibrio harveyi using micro RNAs from mucous exosomes.

Mol Immunol 2020 12 12;128:268-276. Epub 2020 Nov 12.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China. Electronic address:

Exosomes are important mediators of vesicle transportation and contain microRNAs (miRNAs) that mediate transcriptional gene knockout and silencing in biological processes. Moreover, exosomic miRNAs are promising biomarkers for disease diagnosis and physiological status indication in many species, including fish. The impact of the Vibrio harveyi pathogen on Cynoglossus semilaevis aquaculture is becoming more and more serious as the industry expands. To overcome this challenge, miRNAs in mucous exosomes were screened by small RNA sequencing and verified by quantitative real-time PCR to develop biomarkers. This is the first capture of exosomes from flatfish mucus coupled with miRNA profiling. The results revealed significant differences in expression levels of some miRNAs between infected and healthy fish. Three unique miRNAs were identified for V. harveyi infection diagnosis; expression levels of dre-miR-205-5p and dre-miR-205-5p in infected fish were significantly lower than controls, while dre-miR-100-5p expression was higher. These miRNAs in mucous exosomes could be used to differentiate diseased and healthy fish in an early screening method with practical value for breeding disease-resistant C. semilaevis.
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http://dx.doi.org/10.1016/j.molimm.2020.11.004DOI Listing
December 2020

A combination of genome-wide association study screening and SNaPshot for detecting sex-related SNPs and genes in Cynoglossus semilaevis.

Comp Biochem Physiol Part D Genomics Proteomics 2020 09 9;35:100711. Epub 2020 Jul 9.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China. Electronic address:

Chinese tongue sole (Cynoglossus semilaevis) males and females exhibit great differences in growth rate and appearance. The species is heterogametic (ZW/ZZ) and has sex-reversed "pseudomales" that are genetically female and physiologically male. In this study, we identified eight sex-specific single nucleotide polymorphism (SNP) markers for the sex identification of C. semilaevis by using a combination of genome-wide association study (GWAS) screening and SnaPshot validation. Candidate SNPs were screened using genotyping by sequencing to perform GWAS of the differential SNPs between the sexes of C. semilaevis. The SNP loci were amplified using a multiplex PCR system and detected via SNaPshot, which enables multiplexing of up to 30-40 SNPs in a single assay and ensures high accuracy of the results. The molecular markers detected in our study were used to successfully identify normal males and pseudomales from 45 caught and 40 cultured C. semilaevis specimens. Linkage disequilibrium analysis showed that the eight SNP loci were related to each other, with a strong linkage. Moreover, we investigated the expression of prdm6 mRNA containing a missense SNP and confirmed that the gene is differentially expressed in the gonads of the different sexes of C. semilaevis; the expression of prdm6 mRNA was significantly higher in the males than in the females and pseudomales. This means prdm6 may be related to sex differentiation in C. semilaevis.
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http://dx.doi.org/10.1016/j.cbd.2020.100711DOI Listing
September 2020

Large scale SNP unearthing and genetic architecture analysis in sea-captured and cultured populations of Cynoglossus semilaevis.

Genomics 2020 09 11;112(5):3238-3246. Epub 2020 Jun 11.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education, Shanghai 201306, China;International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology, Shanghai 201306, China; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai 201306, China. Electronic address:

Knowledge on population structure and genetic diversity is a focal point for association mapping studies and genomic selection. Genotyping by sequencing (GBS) represents an innovative method for large scale SNP detection and genotyping of genetic resources. Here we used the GBS approach for the genome-wide identification of SNPs in a collection of Cynoglossus semilaevis and for the assessment of the level of genetic diversity in C. semilaevis genotypes. GBS analysis generated a total of 55.12 Gb high-quality sequence data, with an average of 0.63 Gb per sample. The total number of SNP markers was 563, 109. In order to explore the genetic diversity of C. semilaevis and to select a minimal core set representing most of the total genetic variation with minimum redundancy, C. semilaevis sequences were analyzed using high quality SNPs. Based on hierarchical clustering, it was possible to divide the collection into 2 clusters. The marine fishing populations were clustered and clearly separated from the cultured populations, and the cultured populations from Hebei was also distinct from the other two local populations. These analyses showed that genotypes were clustered based on species-related features. Differential significant SNPs were also captured and validated by GBS and SNaPshot, with linkage disequilibrium and haplotype analysis, seven SNPs have been confirmed to have obvious differentiation in two populations, which may be used as the characteristic evaluation sites of sea-captured and cultured Cynoglossus semilaevis populations. And SNP markers and information on population structure developed in this study will undoubtedly support genome-wide association mapping studies and marker-assisted selection programs. These differential SNPs could be also employed as the characteristic evaluation sites of sea-captured and cultured Cynoglossus semilaevis populations in future.
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http://dx.doi.org/10.1016/j.ygeno.2020.06.013DOI Listing
September 2020

Identification and application of piwi-interacting RNAs from seminal plasma exosomes in Cynoglossus semilaevis.

BMC Genomics 2020 Apr 15;21(1):302. Epub 2020 Apr 15.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University), Ministry of Education; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, 201306, China.

Background: Piwi-interacting RNAs (piRNAs) have been linked to epigenetic and post-transcriptional gene silencing of retrotransposons in germ line cells, particularly in spermatogenesis. Exosomes are important mediators of vesicle transport, and the piRNAs in exosomes might play an important role in cell communication and signal pathway regulation. Moreover, exosomic piRNAs are promising biomarkers for disease diagnosis and physiological status indication. We used Cynoglossus semilaevis because of its commercial value and its sexual dimorphism, particularly the sex reversed "pseudomales" who have a female karyotype, produce sperm, and copulate with normal females to produce viable offspring.

Results: To determine whether piRNAs from fish germ line cells have similar features, seminal plasma exosomes from half-smooth tongue sole, C. semilaevis, were identified, and their small RNAs were sequenced and analysed. We identified six signature piRNAs as biomarkers in exosomes of seminal plasma from males and pseudomale C. semilaevis. Bioinformatic analysis showed that all six signatures were sex-related, and four were DNA methylation-related and transposition-related piRNAs. Their expression profiles were verified using real-time quantitative PCR. The expression of the signature piRNAs was markedly higher in males than in pseudomales. The signature piRNAs could be exploited as male-specific biomarkers in this fish.

Conclusions: These signatures provide an effective tool to explore the regulatory mechanism of sex development in C. semilaevis and may provide guidance for future research on the function of piRNAs in the generative mechanism of sex reversed "pseudomales" in C. semilaevis.
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http://dx.doi.org/10.1186/s12864-020-6660-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7158113PMC
April 2020

Identification and characterization of the melanocortin 1 receptor gene (MC1R) in hypermelanistic Chinese tongue sole (Cynoglossus semilaevis).

Fish Physiol Biochem 2020 Jun 6;46(3):881-890. Epub 2020 Jan 6.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Ministry of Education, International Research Center for Marine Biosciences, Ministry of Science and Technology, National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, 201306, China.

The Chinese tongue sole (Cynoglossus semilaevis) is a flatfish with distinctive asymmetry in its body coloration. The melanism (hyperpigmentation) in both the blind side and ocular side of C. semilaevis gives it an extremely low commercial value. However, the fundamental molecular mechanism of this melanism remains unclear. Melanocortin 1 receptor (MC1R), a GTP-binding protein-coupled receptor, is considered to play a vital role in the physiology of the vertebrate pigment system. In order to confirm the contribution of MC1R to the body coloration of C. semilaevis, the expression levels of Mc1r mRNA were measured in seven tissue types at different developmental stages of normal and melanistic C. semilaevis. The expression levels of Mc1r mRNA in the heart, brain, liver, kidney, ocular-side skin, and blind-side skin of melanistic C. semilaevis were significantly higher than that of normal C. semilaevis in all developmental stages. Moreover, the knocking down of Mc1r in the C. semilaevis liver cell line (HTLC) increased the expression of the downstream genes microphthalmia transcription factor (Mitf) and tyrosinase-related protein 1 (Tyrp1) in the pigmentation pathway. Thus, the present data suggest that MC1R might play important roles in Tyrp1- and Mitf-mediated pigment synthesis in C. semilaevis.
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http://dx.doi.org/10.1007/s10695-019-00758-8DOI Listing
June 2020

Seminal Plasma Exosomes: Promising Biomarkers for Identification of Male and Pseudo-Males in Cynoglossus semilaevis.

Mar Biotechnol (NY) 2019 Jun 12;21(3):310-319. Epub 2019 Mar 12.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources (Shanghai Ocean University, Ministry of Education; International Research Center for Marine Biosciences at Shanghai Ocean University, Ministry of Science and Technology; National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, 201306, China.

In mammals, small RNAs enclosed in exosomes have been identified as appropriate signatures for disease diagnosis. However, there is limited information on exosomes derived from seminal plasma, and few studies have reported analyzed the composition of exosomes and enclosed small RNAs in fish. The half-smooth tongue sole (Cynoglossus semilaevis) is an economically important fish for aquaculture, and it exhibits sexual dimorphism: the female gender show higher growth rates and larger body sizes than males. Standard karyotype analysis and artificial gynogenesis tests have revealed that this species uses heterogametic sex determination (ZW/ZZ), and so-called sex-reversed pseudo-males exist. In this study, we successfully identified exosomes in the seminal plasma of C. semilaevis; to the best of our knowledge, this is the first report of exosomes in fish seminal plasma. Analysis of the nucleotide composition showed that miRNAs were dominant in the exosomes, and the miRNAs were sequenced and compared to identify signature miRNAs as sexual biomarkers. Moreover, target genes of the signature miRNAs were predicted by sequence matching and annotation. Finally, four miRNAs (dre-miR-141-3P, dre-miR-10d-5p, ssa-miR-27b-3p, and ssa-miR-23a-3p) with significant differential expression in the males and pseudo-males were selected from the signature candidate miRNAs as markers for sex identification, and their expression profiles were verified using real-time quantitative PCR. Our findings could provide an effective detection method for sex differentiation in fish.
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http://dx.doi.org/10.1007/s10126-019-09881-2DOI Listing
June 2019

Dorsal fin development in flounder, Paralichthys olivaceus: Bud formation and its cellular origin.

Gene Expr Patterns 2017 11 22;25-26:22-28. Epub 2017 Apr 22.

The Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai 201306, China. Electronic address:

The development of the median fin has not been investigated extensively in teleosts, although in other fishes it has been proposed that it involves the same genetic programs operating in the paired appendages. Adult median fins develop from the larval bud; therefore an investigation of fin bud formation and its cellular origin is essential to understanding the maturation mechanisms. In Paralichthys olivaceus, skeletogenesis proceeds from an anterior to posterior direction providing a good opportunity to study the formation of dorsal fin bud. An apical ectodermal ridge appeared at the basal stratum of the presumptive dorsal fin was first observed at 3 days post hatching. Then the apical ectodermal fold formed as the bud outgrew in 6 days post-hatch larvae. The bud continued to grow, breaking through the dorsal fin fold in 9 days post-hatch larvae. At 13 days post-hatch, the bud grew beyond the edge of the fin fold and formed into the four future rays. Molecular markers of cell type showed the existence of neural crest cells, scleroblasts and sclerotomes in the dorsal fin bud. The earliest gene expression in the dorsal fin bud was Hoxd10 at 3 days post-hatch larvae, then Hoxd9, Hoxd11 and Hoxd12. This indicates Hoxd10 might be a candidate molecular marker of the bud formation site. Some key molecular markers for paired appendage development, such as FGF8, Wnt7, and Shh were expressed at the apical ectodermal ridge and later the apical ectodermal fold. Moreover, the form of the dorsal fin bud could be inhibited by Hh pathway inhibitor, further indicating that common basic molecular mechanisms might be utilized by median fins.
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http://dx.doi.org/10.1016/j.gep.2017.04.003DOI Listing
November 2017

The genome and transcriptome of Japanese flounder provide insights into flatfish asymmetry.

Nat Genet 2017 01 5;49(1):119-124. Epub 2016 Dec 5.

Yellow Sea Fisheries Research Institute, CAFS, Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Qingdao, China.

Flatfish have the most extreme asymmetric body morphology of vertebrates. During metamorphosis, one eye migrates to the contralateral side of the skull, and this migration is accompanied by extensive craniofacial transformations and simultaneous development of lopsided body pigmentation. The evolution of this developmental and physiological innovation remains enigmatic. Comparative genomics of two flatfish and transcriptomic analyses during metamorphosis point to a role for thyroid hormone and retinoic acid signaling, as well as phototransduction pathways. We demonstrate that retinoic acid is critical in establishing asymmetric pigmentation and, via cross-talk with thyroid hormones, in modulating eye migration. The unexpected expression of the visual opsins from the phototransduction pathway in the skin translates illumination differences and generates retinoic acid gradients that underlie the generation of asymmetry. Identifying the genetic underpinning of this unique developmental process answers long-standing questions about the evolutionary origin of asymmetry, but it also provides insight into the mechanisms that control body shape in vertebrates.
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http://dx.doi.org/10.1038/ng.3732DOI Listing
January 2017

Comparative analysis of the neurula transcriptomes of two species of flatfishes: Platichthys stellatus and Paralichthys olivaceus.

Gene 2017 Jan 15;596:147-153. Epub 2016 Oct 15.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai 201306, China. Electronic address:

Flatfish with left-right eye asymmetry are the most significant among vertebrates. However, the genetic basis for the control of this characteristic is still unclear. We propose that the gene(s) for eye asymmetry initially control minor differences in cell number in the tissues around the eyes during eye development. This minor difference is then amplified, causing eye migration during metamorphosis. Therefore, comparing the neurula transcriptomes between flatfish species with different eye-reversal mutants may provide very useful information to screen for genes involved in eye asymmetry. In this study, two cDNA libraries constructed from neurulas of P. stellatus (high ratio of eye reversal) and P. olivaceus (very low ratio of eye reversal) were sequenced and compared. There were 8121 and 8108 unigenes annotated to 32 categories in P. stellatus and P. olivaceus, respectively, and the highest KEGG pathways in both species were 'signal transduction', 'immune system', and 'endocrine system'. In total, 62,692 and 18,938 putative single nucleotide polymorphisms (SNPs) were predicted in the P. stellatus and P. olivaceus transcriptomes, respectively. Furthermore, 8026 SNPs found in P. stellatus did not exist in P. olivaceus. Fifty-one SNPs were identified in nine genes (Fgf7, Wnt9, Sfrp2, Bmpr1B, Bmpr2, Pax3, Pax6, Six1 and Tgfβr2) related to eye development. In particular, Tgfβr2 with Asp77Glu found in P. stellatus but not in P. olivaceus will provide important information for screening genes associated with eye asymmetry.
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http://dx.doi.org/10.1016/j.gene.2016.10.020DOI Listing
January 2017

Change of body height is regulated by thyroid hormone during metamorphosis in flatfishes and zebrafish.

Gen Comp Endocrinol 2016 09 20;236:9-16. Epub 2016 Jun 20.

The Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai 201306, China. Electronic address:

Flatfishes with more body height after metamorphosis should be better adapted to a benthic lifestyle. In this study, we quantified the changes in body height during metamorphosis in two flatfish species, Paralichthys olivaceus and Platichthys stellatus. The specific pattern of cell proliferation along the dorsal and ventral edge of the body to allow fast growth along the dorsal/ventral axis might be related to the change of body height. Thyroid hormone (T4 and T3) and its receptors showed distribution or gene expression patterns similar to those seen for the cell proliferation. 2-Mercapto-1-methylimidazole, an inhibitor of endogenous thyroid hormone synthesis, inhibited cell proliferation and decreased body height, suggesting that the change in body shape was dependent on the local concentration of thyroid hormone to induce cell proliferation. In addition, after treatment with 2-mercapto-1-methylimidazole, zebrafish larvae were also shown to develop a slimmer body shape. These findings enrich our knowledge of the role of thyroid hormone during flatfish metamorphosis, and the role of thyroid hormone during the change of body height during post-hatching development should help us to understand better the biology of metamorphosis in fishes.
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http://dx.doi.org/10.1016/j.ygcen.2016.06.028DOI Listing
September 2016

The complete mitochondrial genome sequence of Yongeichthys criniger and phylogenetic studies of Gobiidae.

Mitochondrial DNA A DNA Mapp Seq Anal 2017 03 29;28(2):281-282. Epub 2015 Dec 29.

a Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources , Shanghai Ocean University, Ministry of Education , Shanghai , China.

Yongeichthys criniger belongs to Gobiidae, Gobioidei, and Perciformes in taxonomy. Its mitochondrial genome was first determined, which consists of 13 typical vertebrate protein-coding genes, 22 tRNA, 2 rRNA genes, and 1 control region. The mitogenome base's composition is 27.28% for A, 26.12% for T, 28.98% for C, and 17.62% for G. The phylogenic analysis involves 32 Gobiidae species in GenBank database. The results will provide more molecular information for the further studies on species identification and phylogenic evolution of Gobiidae.
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http://dx.doi.org/10.3109/19401736.2015.1118080DOI Listing
March 2017

Different ossification patterns of intermuscular bones in fish with different swimming modes.

Biol Open 2015 Nov 24;4(12):1727-32. Epub 2015 Nov 24.

The Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai 201306, China

Intermuscular bones are found in the myosepta in teleosts. However, there is very little information on the development and ossification of these intermuscular bones. In this study, we performed an in-depth investigation of the ossification process during development in zebrafish (Danio rerio) and Japanese eel (Anguilla japonica). In Japanese eel, a typical anguilliform swimmer, the intermuscular bones ossified predominantly from the anterior to the posterior. By contrast, in the zebrafish, a sub-carangiform or carangiform swimmer, the intermuscular bones ossified predominantly from the posterior to the anterior regions of the fish. Furthermore, tail amputation affected the ossification of the intermuscular bones. The length of the intermuscular bones in the posterior area became significantly shorter in tail-amputated zebrafish and Japanese eels, and both had less active and lower swimming speeds; this indicates that swimming might induce the ossification of the intermuscular bones. Moreover, when a greater length of tail was amputated in the zebrafish, the intermuscular bones became even shorter. Tail amputation affected the length and ossification of intermuscular bones in the anterior part of the fish, close to the head, differently between the two fish: they became significantly shorter in the zebrafish, but did not in the Japanese eel. This might be because tail amputation did not significantly affect the undulations in the anterior of the Japanese eel, especially near the head. This study shows that the ossification of intermuscular bones might be induced through mechanical force loadings that are produced by swimming.
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http://dx.doi.org/10.1242/bio.012856DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4736024PMC
November 2015

Identification of tetrodotoxin-producing bacteria from goby Yongeichthys criniger.

Toxicon 2015 Sep 1;104:46-51. Epub 2015 Aug 1.

The Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai 201306, China. Electronic address:

Toxic goby fish (Yongeichthys criniger) containing tetrodotoxin (TTX), from Zhanjiang, Guangdong province, China, were screened for TTX-producing bacteria. Two toxic bacterial strains were isolated from the liver of Y. criniger and respectively denoted XC3-3 and XL-1. TTX production by the strains was confirmed by mouse bioassay, enzyme-linked immunosorbent assay and high performance liquid chromatography coupled with mass spectrometry. Based on morphological, physiological and biochemical characteristics and 16S rDNA phylogenetic analysis, strain XC3-3 was identified as Enterobacter cloaca and XL-1 was closely related to Rahnella aquatilis. These findings show for the first time that TTX-producing bacteria are symbiotic bacteria in goby and suggest that bacterial strains are at least partially responsible for TTX accumulation in Y. criniger.
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http://dx.doi.org/10.1016/j.toxicon.2015.07.335DOI Listing
September 2015

Production level of tetrodotoxin in Aeromonas is associated with the copy number of a plasmid.

Toxicon 2015 Jul 23;101:27-34. Epub 2015 Apr 23.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai 201306, China. Electronic address:

Tetrodotoxin (TTX) has been identified from taxonomically diverse organisms. Artificial synthesis of TTX has been reported, but the biosynthetic pathway of TTX remains elusive. In this study, we found TTX producing ability was associated with the copy number of plasmid pNe-1 in Aeromonas strain Ne-1 during fermentation, suggesting that at least one gene encoding a TTX-synthesis enzyme is located on this plasmid. Compared with bacterial genomes, plasmids are small and easier to screen for genes associated with TTX biosynthesis. The approximately 100 kb genome of pNe-1 was sequenced. The plasmid contains 60 complete open reading frames (orfs) of which 32 (53.3%) encode hypothetical proteins. Seven genes are related to the type IV secretion system (T4SS) and 2 genes are related to transposons, indicating that the TTX-producing bacterium Aeromonas might have the ability to transfer the TTX biosynthesis gene via the conjugation and contagion of plasmid pNe-1. In addition, we unexpectedly found that Aeromonas Ne-1 contains unknown TTX-degrading materials, indicating there is a homeostatic mechanism to maintain a stable amount of TTX in the bacterium. These results will help us to better understand TTX biosynthesis, the bacterial origin of TTX, and TTX degradation.
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http://dx.doi.org/10.1016/j.toxicon.2015.04.009DOI Listing
July 2015

Distortion of frontal bones results from cell apoptosis by the mechanical force from the up-migrating eye during metamorphosis in Paralichthys olivaceus.

Mech Dev 2015 May 23;136:87-98. Epub 2015 Jan 23.

The Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai 201306, China. Electronic address:

Craniofacial remodeling during flatfish metamorphosis, including eye migration, is perhaps the most striking example of asymmetric postembryonic development in the vertebrate world. The asymmetry of the cranium mainly results from distortion of the frontal bones, which depends on eye migration during metamorphosis. However, it is unclear how the up-migrating eye causes distortion of the frontal bones. In this study, we first show that distortion of the frontal bones during metamorphosis in Paralichthys olivaceus is the result of cell apoptosis, rather than cell autophagy or cell proliferation. Secondly, we report that cell apoptosis in the frontal bones is induced by the mechanical force transferred from the up-migrating eye. The mechanical force from the up-migrating eye signals through FAK to downstream molecules that are integrated into the BMP-2 signal pathway. Finally, it is shown that cell apoptosis in the frontal bones is activated by the intrinsic mitochondrial pathway; the extrinsic death receptor is not involved in this process. Moreover, cell apoptosis in frontal bones is not induced directly by thyroid hormones, which are thought to mediate metamorphosis in flatfishes and directly mediate cell apoptosis during amphibian metamorphosis. These findings help identify the major signaling route used during regulation of frontal bone distortion during metamorphosis in flatfish, and indicate that the asymmetry of the cranium, or at least the distortion of frontal bones, is the result of rather than the reason underlying eye migration.
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http://dx.doi.org/10.1016/j.mod.2015.01.001DOI Listing
May 2015

Complete mitochondrial DNA sequence of the Eastern keelback mullet Liza affinis.

Mitochondrial DNA A DNA Mapp Seq Anal 2016 05 25;27(3):2178-9. Epub 2014 Nov 25.

a Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources , Shanghai Ocean University, Ministry of Education , Shanghai , China.

Eastern keelback mullet (Liza affinis) inhabits inlet waters and estuaries of rivers. In this paper, we initially determined the complete mitochondrial genome of Liza affinis. The entire mtDNA sequence is 16,831 bp in length, including 2 rRNA genes, 22 tRNA genes, 13 protein-coding genes and 1 putative control region. Its order and numbers of genes are similar to most bony fishes.
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http://dx.doi.org/10.3109/19401736.2014.982614DOI Listing
May 2016

Complete mitochondrial DNA sequence of marble goby, Oxyeleotris marmorata (Bleeker, 1852).

Mitochondrial DNA A DNA Mapp Seq Anal 2016 20;27(2):817-8. Epub 2014 May 20.

a Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources , Shanghai Ocean University, Ministry of Education , Shanghai , China and.

Marble goby, Oxyeleotris marmorata (Bleeker) is a large-scale invasive goby in China. In this study, the mitochondrial genome of marble goby was firstly determined. The entire mtDNA sequence was 16,556 bp in length with 13 protein-coding genes, 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs) and control region (CR). Its mitochondrial genome has the common features with those of other bony fishes with respect to gene arrangement, base composition, and tRNA structures.
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http://dx.doi.org/10.3109/19401736.2014.919456DOI Listing
October 2016

Human holocarboxylase synthetase with a start site at methionine-58 is the predominant nuclear variant of this protein and has catalytic activity.

Biochem Biophys Res Commun 2011 Aug 23;412(1):115-20. Epub 2011 Jul 23.

Department of Nutrition and Health Sciences, University of Nebraska at Lincoln, Lincoln, NE, USA.

Holocarboxylase synthetase (HLCS) catalyzes the covalent binding of biotin to both carboxylases in extranuclear structures and histones in cell nuclei, thereby mediating important roles in intermediary metabolism, gene regulation, and genome stability. HLCS has three putative translational start sites (methionine-1, -7, and -58), but lacks a strong nuclear localization sequence that would explain its participation in epigenetic events in the cell nucleus. Recent evidence suggests that small quantities of HLCS with a start site in methionine-58 (HLCS58) might be able to enter the nuclear compartment. We generated the following novel insights into HLCS biology. First, we generated a novel HLCS fusion protein vector to demonstrate that methionine-58 is a functional translation start site in human cells. Second, we used confocal microscopy and western blots to demonstrate that HLCS58 enters the cell nucleus in meaningful quantities, and that full-length HLCS localizes predominantly in the cytoplasm but may also enter the nucleus. Third, we produced recombinant HLCS58 to demonstrate its biological activity toward catalyzing the biotinylation of both carboxylases and histones. Collectively, these observations are consistent with roles of HLCS58 and full-length HLCS in nuclear events. We conclude this report by proposing a novel role for HLCS in epigenetic events, mediated by physical interactions between HLCS and other chromatin proteins as part of a larger multiprotein complex that mediates gene repression.
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http://dx.doi.org/10.1016/j.bbrc.2011.07.055DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3159853PMC
August 2011

Cytosine methylation in miR-153 gene promoters increases the expression of holocarboxylase synthetase, thereby increasing the abundance of histone H4 biotinylation marks in HEK-293 human kidney cells.

J Nutr Biochem 2012 Jun 20;23(6):635-9. Epub 2011 Jul 20.

Department of Nutrition and Health Sciences, University of Nebraska at Lincoln, Lincoln, NE 68583, USA.

Holocarboxylase synthetase (HCS) plays an essential role in catalyzing the biotinylation of carboxylases and histones. Biotinylated carboxylases are important for the metabolism of glucose, lipids and leucine; biotinylation of histones plays important roles in gene regulation and genome stability. Recently, we reported that HCS activity is partly regulated by subcellular translocation events and by miR-539. Here we tested the hypothesis that the HCS 3'-untranslated region (3'-UTR) contains binding sites for miR other than miR-539. A binding site for miR-153 was predicted to reside in the HCS 3'-UTR by using in silico analyses. When miR-153 site was overexpressed in transgenic HEK-293 human embryonic kidney cells, the abundance of HCS mRNA decreased by 77% compared with controls. In silico analyses also predicted three putative cytosine methylation sites in two miR-153 genes; the existence of these sites was confirmed by methylation-sensitive polymerase chain reaction. When cytosines were demethylated by treatment with 5-aza-2'-deoxycytidine, the abundance of miR-153 increased by more than 25 times compared with untreated controls, and this increase coincided with low levels of HCS and histone biotinylation. Together, this study provides novel insights into the mechanisms of novel epigenetic synergies among folate-dependent methylation events, miR and histone biotinylation.
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http://dx.doi.org/10.1016/j.jnutbio.2011.03.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3208029PMC
June 2012

mRNA/microRNA Profile at the Metamorphic Stage of Olive Flounder (Paralichthys olivaceus).

Comp Funct Genomics 2011 19;2011:256038. Epub 2011 Apr 19.

The Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai 201306, China.

Flatfish is famous for the asymmetric transformation during metamorphosis. The molecular mechanism behind the asymmetric development has been speculated over a century and is still not well understood. To date, none of the metamorphosis-related genes has been identified in flatfish. As the first step to screen metamorphosis-related gene, we constructed a whole-body cDNA library and a whole-body miRNA library in this study and identified 1051 unique ESTs, 23 unique miRNAs, and 4 snoRNAs in premetamorphosing and prometamorphosing Paralichthys olivaceus. 1005 of the ESTs were novel, suggesting that there was a special gene expression profile at metamorphic stage. Four miRNAs (pol-miR-20c, pol-miR-23c, pol-miR-130d, and pol-miR-181e) were novel to P. olivaceus; they were characterized as highly preserved homologies of published miRNAs but with at least one nucleotide differed. Representative 24 mRNAs and 23 miRNAs were quantified during metamorphosis of P. olivaceus by using quantitative RT PCR or stem-loop qRT PCR. Our results showed that 20 of mRNAs might be associated with early metamorphic events, 10 of mRNAs might be related with later metamorphic events, and 16 of miRNAs might be involved in the regulation of metamorphosis. The data provided in this study would be helpful for further identifying metamorphosis-related gene in P. olivaceus.
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http://dx.doi.org/10.1155/2011/256038DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3092494PMC
July 2011

Proliferating cells in suborbital tissue drive eye migration in flatfish.

Dev Biol 2011 Mar 31;351(1):200-7. Epub 2010 Dec 31.

The Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai 201306, PR China.

The left/right asymmetry of adult flatfishes (Pleuronectiformes) is remarkable given the external body symmetry of the larval fish. The best-known change is the migration of their eyes: one eye migrates from one side to the other. Two extinct primitive pleuronectiformes with incomplete orbital migration have again attracted public attention to the mechanism of eye migration, a subject of speculation and research for over a century. Cranial asymmetry is currently believed to be responsible for eye migration. Contrary to that hypothesis, we show here that the initial migration of the eye is caused by cell proliferation in the suborbital tissue of the blind side and that the twist of frontal bone is dependent on eye migration. The inhibition of cell proliferation in the suborbital area of the blind side by microinjected colchicine was able to prevent eye migration and, thereafter, cranial asymmetry in juvenile Solea senegalensis (right sideness, Soleidae), Cynoglossus semilaevis (left sideness, Cynoglossidae), and Paralichthys olivaceus (left sideness, Paralichthyidae) with a bottom-dwelling lifestyle. Our results correct the current misunderstanding that eye migration is driven by the cranial asymmetry and simplify the explanation for broken left/right eye-symmetry. Our findings should help to focus the search on eye migration-related genes associated with cell proliferation. Finally, a novel model is proposed in this research which provides a reasonable explanation for differences in the migrating eye between, and sometimes within, different species of flatfish and which should aid in our overall understanding of eye migration in the ontogenesis and evolution of Pleuronectiformes.
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http://dx.doi.org/10.1016/j.ydbio.2010.12.032DOI Listing
March 2011

Generation and analysis of ESTs from the grass carp, Ctenopharyngodon idellus.

Anim Biotechnol 2010 Oct;21(4):217-25

The Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai, China.

Grass carp, Ctenopharyngodon idellus (Valenciennes, 1844), is an economically important species widely cultured in the world, but its genome research resources are largely lacking. The objectives of this study were to construct normalized cDNA libraries for efficient EST analysis, to generate ESTs from these libraries, and to identify EST-related molecular markers such as microsatellites and single nucleotide polymorphisms (SNPs) for genetic analysis of this species. A total of 6,269 ESTs were generated representing 4,815 unique sequences, from which 105 putative microsatellites and 5,228 SNPs were identified. These genome resources provide the material basis for future genetic and functional analyses in this species.
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http://dx.doi.org/10.1080/10495398.2010.505843DOI Listing
October 2010

Holocarboxylase synthetase is a chromatin protein and interacts directly with histone H3 to mediate biotinylation of K9 and K18.

J Nutr Biochem 2011 May 5;22(5):470-5. Epub 2010 Aug 5.

Department of Nutrition and Health Sciences, University of Nebraska at Lincoln, Lincoln, NE 68583, USA.

Holocarboxylase synthetase (HCS) mediates the binding of biotin to lysine (K) residues in histones H2A, H3 and H4; HCS knockdown disturbs gene regulation and decreases stress resistance and lifespan in eukaryotes. We tested the hypothesis that HCS interacts physically with histone H3 for subsequent biotinylation. Co-immunoprecipitation experiments were conducted and provided evidence that HCS co-localizes with histone H3 in human cells; physical interactions between HCS and H3 were confirmed using limited proteolysis assays. Yeast two-hybrid (Y2H) studies revealed that the N-terminal and C-terminal domains in HCS participate in H3 binding. Recombinant human HCS was produced and exhibited biological activity, as evidenced by biotinylation of its known substrate, recombinant p67. Recombinant histone H3.2 and synthetic H3-based peptides were also good targets for biotinylation by recombinant HCS (rHCS) in vitro, based on tracing histone-bound biotin with [(3)H]biotin, streptavidin and anti-biotin antibody. Biotinylation site-specific antibodies were generated and revealed that both K9 and K18 in H3 were biotinylated by HCS. Collectively, these studies provide conclusive evidence that HCS interacts directly with histone H3, causing biotinylation of K9 and K18. We speculate that the targeting of HCS to distinct regions in human chromatin is mediated by DNA sequence, biotin, RNA, epigenetic marks or chromatin proteins.
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http://dx.doi.org/10.1016/j.jnutbio.2010.04.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2975038PMC
May 2011

Biotin regulates the expression of holocarboxylase synthetase in the miR-539 pathway in HEK-293 cells.

J Nutr 2010 Sep 30;140(9):1546-51. Epub 2010 Jun 30.

Department of Nutrition and Health Sciences, University of Nebraska at Lincoln, Lincoln, Nebraska 68583, USA.

Holocarboxylase synthetase (HCS) catalyzes the covalent binding of biotin to carboxylases and histones. In mammals, the expression of HCS depends on biotin, but the mechanism of regulation is unknown. Here we tested the hypothesis that microRNA (miR) plays a role in the regulation of the HCS gene. Human embryonic kidney cells were used as the primary model, but cell lines from other tissues and primary human cells were also tested. In silico searches revealed an evolutionary conserved binding site for miR-539 in the 3 prime -untranslated region (3 prime -UTR) of HCS mRNA. Transgenic cells and reporter gene constructs were used to demonstrate that miR-539 decreases the expression of HCS at the level of transcription rather than translation; these findings were corroborated in nontransgenic cells. When miR-539 was overexpressed in transgenic cells, the abundance of both HCS and biotinylated histones decreased. The abundance of miR-539 was tissue dependent: fibroblasts gt kidney cells gt intestinal cells gt lymphoid cells. Dose-response studies revealed that the abundance of miR-539 was significantly higher at physiological concentrations of biotin than both biotin-deficient and biotin-supplemented media in all cell lines tested. In kidney cells, the expression of HCS was lower in cells in physiological medium than in deficient and supplemented medium. In contrast, in fibroblasts, lymphoid cells, and intestinal cells, there was no apparent link between miR-539 abundance and HCS expression, suggesting that factors other than miR-539 also contribute to the regulation of HCS expression in some tissues. Collectively, the results of this study suggest that miR-539 is among the factors sensing biotin and regulating HCS.
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http://dx.doi.org/10.3945/jn.110.126359DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2924595PMC
September 2010

A novel TTX-producing Aeromonas isolated from the ovary of Takifugu obscurus.

Toxicon 2010 Sep 1;56(3):324-9. Epub 2010 Apr 1.

Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources, Shanghai Ocean University, Ministry of Education, Shanghai 201306, China.

Puffer fish (Takifugu obscurus) from the Yangtze River of China were screened for tetrodotoxin-producing bacteria. An Aeromonas strain was isolated from the ovary of the puffer fish and was shown to produce tetrodotoxin; this strain was denoted Ne-1. The identity of tetrodotoxin produced by strain Ne-1 was confirmed by mouse bioassay, high performance liquid chromatography coupled with mass chromatography (LC-MS), and ELISA. Strain Ne-1 was characterized morphologically, biochemically, and by 16S rDNA phylogenetic analysis; these analyses suggested that strain Ne-1 is closely related to Aeromonas molluscorum. Given that strain Ne-1 was isolated from the ovary of T. obscurus, we propose that the TTX-producing Aeromonas sp. is a parasite or symbiotic bacterium rather than a sample contaminant. Collectively, our studies suggest that Aeromonas sp. strain Ne-1 produces tetrodotoxin in T. obscurus.
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http://dx.doi.org/10.1016/j.toxicon.2010.03.019DOI Listing
September 2010

Assembly of 500,000 inter-specific catfish expressed sequence tags and large scale gene-associated marker development for whole genome association studies.

Genome Biol 2010 Jan 22;11(1):R8. Epub 2010 Jan 22.

The Fish Molecular Genetics and Biotechnology Laboratory, Department of Fisheries and Allied Aquacultures and Program of Cell and Molecular Biosciences, Aquatic Genomics Unit, 203 Swingle Hall, Auburn University, Auburn, AL 36849, USA.

Background: Through the Community Sequencing Program, a catfish EST sequencing project was carried out through a collaboration between the catfish research community and the Department of Energy's Joint Genome Institute. Prior to this project, only a limited EST resource from catfish was available for the purpose of SNP identification.

Results: A total of 438,321 quality ESTs were generated from 8 channel catfish (Ictalurus punctatus) and 4 blue catfish (Ictalurus furcatus) libraries, bringing the number of catfish ESTs to nearly 500,000. Assembly of all catfish ESTs resulted in 45,306 contigs and 66,272 singletons. Over 35% of the unique sequences had significant similarities to known genes, allowing the identification of 14,776 unique genes in catfish. Over 300,000 putative SNPs have been identified, of which approximately 48,000 are high-quality SNPs identified from contigs with at least four sequences and the minor allele presence of at least two sequences in the contig. The EST resource should be valuable for identification of microsatellites, genome annotation, large-scale expression analysis, and comparative genome analysis.

Conclusions: This project generated a large EST resource for catfish that captured the majority of the catfish transcriptome. The parallel analysis of ESTs from two closely related Ictalurid catfishes should also provide powerful means for the evaluation of ancient and recent gene duplications, and for the development of high-density microarrays in catfish. The inter- and intra-specific SNPs identified from all catfish EST dataset assembly will greatly benefit the catfish introgression breeding program and whole genome association studies.
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http://dx.doi.org/10.1186/gb-2010-11-1-r8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2847720PMC
January 2010