Publications by authors named "Li Ronghui"

41 Publications

Hydrographic data inspection and disaster monitoring using shipborne radar small range images with electronic navigation chart.

PeerJ Comput Sci 2020 14;6:e290. Epub 2020 Sep 14.

Maritime College, Guangdong Ocean University, Zhanjiang, Guangdong, China.

Shipborne radars cannot only enable navigation and collision avoidance but also play an important role in the fields of hydrographic data inspection and disaster monitoring. In this paper, target extraction methods for oil films, ships and coastlines from original shipborne radar images are proposed. First, the shipborne radar video images are acquired by a signal acquisition card. Second, based on remote sensing image processing technology, the radar images are preprocessed, and the contours of the targets are extracted. Then, the targets identified in the radar images are integrated into an electronic navigation chart (ENC) by a geographic information system. The experiments show that the proposed target segmentation methods of shipborne radar images are effective. Using the geometric feature information of the targets identified in the shipborne radar images, information matching between radar images and ENC can be realized for hydrographic data inspection and disaster monitoring.
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http://dx.doi.org/10.7717/peerj-cs.290DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7924651PMC
September 2020

An Attention-Enhanced Multi-Scale and Dual Sign Language Recognition Network Based on a Graph Convolution Network.

Authors:
Lu Meng Ronghui Li

Sensors (Basel) 2021 Feb 5;21(4). Epub 2021 Feb 5.

College of Information Science and Engineering, Northeastern University, Shenyang 110000, China.

Sign language is the most important way of communication for hearing-impaired people. Research on sign language recognition can help normal people understand sign language. We reviewed the classic methods of sign language recognition, and the recognition accuracy is not high enough because of redundant information, human finger occlusion, motion blurring, the diversified signing styles of different people, and so on. To overcome these shortcomings, we propose a multi-scale and dual sign language recognition Network (SLR-Net) based on a graph convolutional network (GCN). The original input data was RGB videos. We first extracted the skeleton data from them and then used the skeleton data for sign language recognition. SLR-Net is mainly composed of three sub-modules: multi-scale attention network (MSA), multi-scale spatiotemporal attention network (MSSTA) and attention enhanced temporal convolution network (ATCN). MSA allows the GCN to learn the dependencies between long-distance vertices; MSSTA can directly learn the spatiotemporal features; ATCN allows the GCN network to better learn the long temporal dependencies. The three different attention mechanisms, multi-scale attention mechanism, spatiotemporal attention mechanism, and temporal attention mechanism, are proposed to further improve the robustness and accuracy. Besides, a keyframe extraction algorithm is proposed, which can greatly improve efficiency by sacrificing a little accuracy. Experimental results showed that our method can reach 98.08% accuracy rate in the CSL-500 dataset with a 500-word vocabulary. Even on the challenging dataset DEVISIGN-L with a 2000-word vocabulary, it also reached a 64.57% accuracy rate, outperforming other state-of-the-art sign language recognition methods.
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http://dx.doi.org/10.3390/s21041120DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7915156PMC
February 2021

Endothelium-derived stromal cells contribute to hematopoietic bone marrow niche formation.

Cell Stem Cell 2021 Apr 8;28(4):653-670.e11. Epub 2021 Feb 8.

Department of Hematology, Erasmus MC Cancer Institute, Rotterdam 3015 CN, the Netherlands. Electronic address:

Bone marrow stromal cells (BMSCs) play pivotal roles in tissue maintenance and regeneration. Their origins, however, remain incompletely understood. Here we identify rare LNGFR cells in human fetal and regenerative bone marrow that co-express endothelial and stromal markers. This endothelial subpopulation displays transcriptional reprogramming consistent with endothelial-to-mesenchymal transition (EndoMT) and can generate multipotent stromal cells that reconstitute the bone marrow (BM) niche upon transplantation. Single-cell transcriptomics and lineage tracing in mice confirm robust and sustained contributions of EndoMT to bone precursor and hematopoietic niche pools. Interleukin-33 (IL-33) is overexpressed in subsets of EndoMT cells and drives this conversion process through ST2 receptor signaling. These data reveal generation of tissue-forming BMSCs from mouse and human endothelial cells and may be instructive for approaches to human tissue regeneration.
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http://dx.doi.org/10.1016/j.stem.2021.01.006DOI Listing
April 2021

Heterogeneous bone-marrow stromal progenitors drive myelofibrosis via a druggable alarmin axis.

Cell Stem Cell 2021 Apr 9;28(4):637-652.e8. Epub 2020 Dec 9.

Department of Hematology, Erasmus Medical Center, Rotterdam 3015GD, the Netherlands; Department of Cell Biology, Institute for Biomedical Engineering, Faculty of Medicine, RWTH Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany; Oncode Institute, Erasmus Medical Center, Rotterdam 3015GD, the Netherlands. Electronic address:

Functional contributions of individual cellular components of the bone-marrow microenvironment to myelofibrosis (MF) in patients with myeloproliferative neoplasms (MPNs) are incompletely understood. We aimed to generate a comprehensive map of the stroma in MPNs/MFs on a single-cell level in murine models and patient samples. Our analysis revealed two distinct mesenchymal stromal cell (MSC) subsets as pro-fibrotic cells. MSCs were functionally reprogrammed in a stage-dependent manner with loss of their progenitor status and initiation of differentiation in the pre-fibrotic and acquisition of a pro-fibrotic and inflammatory phenotype in the fibrotic stage. The expression of the alarmin complex S100A8/S100A9 in MSC marked disease progression toward the fibrotic phase in murine models and in patient stroma and plasma. Tasquinimod, a small-molecule inhibiting S100A8/S100A9 signaling, significantly ameliorated the MPN phenotype and fibrosis in JAK2V617F-mutated murine models, highlighting that S100A8/S100A9 is an attractive therapeutic target in MPNs.
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http://dx.doi.org/10.1016/j.stem.2020.11.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8024900PMC
April 2021

Low-dose IL-2 therapy compensates for metabolic shifts and reverses anxiety-like behavior in PD-1 deficiency-induced autoimmunity.

Cell Mol Immunol 2020 Oct 16. Epub 2020 Oct 16.

School of Pharmaceutical Sciences, Shandong Analysis and Test Center, Laboratory of Immunology for Environment and Health, Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong, China.

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http://dx.doi.org/10.1038/s41423-020-00562-yDOI Listing
October 2020

A study on the occurrence of black water in reservoirs in Eucalyptus Plantation region.

Environ Sci Pollut Res Int 2020 Oct 24;27(28):34927-34940. Epub 2020 Jun 24.

Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China.

Tianbao reservoir in southern China (surrounded by Eucalyptus plantation) serves as a source of drinking water for the inhabitants. However, the reservoir water experiences black water (BW) of which the cause remains unclear. In this study, field observation and simulated laboratory experiment were conducted to understand the cause of the BW. The diffusive gradient in thin-film (DGT) device monitored the spatial changes in concentration of iron (Fe), manganese (Mn), sulfide (S), and dissolved organic carbon (DOC) at the SWI. The planar optode (PO) showed that hypoxia contributed immensely to the high positive fluxes Fe, Mn, and S measured, which co-precipitated to form black materials (FeS and MnS) at the SWI. The co-precipitation between Fe-S and Mn-S was supported by their significant positive correlation (Fe-S: r > 0.05, p < 0.05, Mn-S: r > 0.2, p < 0.05). Significant reduction (p < 0.05) in tannins concentration from November (strong thermal stratification) to December (weak thermal stratification) indicated that Fe and tannins reacted during the mixing of reservoir water in December due to weak stratification. The simulated experiment confirmed that fresh Eucalyptus leaves produces a significant (p < 0.05) amount of tannins during hypoxia and reacts with Fe to produce black water. A high positive correlation (r > 0.8) between Fe and DOC demonstrated that Fe and DOC combined and contributed to the reservoir water blackening. The study provides a better understanding on the impact of Eucalyptus plantation on water quality and provide guidance for scientific planting of Eucalyptus plantation in reservoir basins in southern China to ensure safe drinking water.
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http://dx.doi.org/10.1007/s11356-020-09613-3DOI Listing
October 2020

High resolution evidence of iron-phosphorus-sulfur mobility at hypoxic sediment water interface: An insight to phosphorus remobilization using DGT-induced fluxes in sediments model.

Sci Total Environ 2020 Jul 28;724:138204. Epub 2020 Mar 28.

Key Laboratory of Integrated Regulation and Resources Development of Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China.

The deterioration of reservoirs in southern China due to the kinetics of Iron (Fe), Phosphorus (P) and sulphide (S) at the sediment-water interface (SWI) is a major problem that needs urgent attention. Studies on the biogeochemistry of Fe, P, and S using high-resolution profile techniques in reservoirs in this region are limited. The diffusive gradient in thin films (DGT) technique, high-resolution dialysis, DGT-computer imaging densitometry (CID), DGT-induced fluxes in sediments (DIFS) and planar optode (PO) device were used to describe the dynamics Fe-P-S in SWI during hypoxia. The results showed the release of Fe-P-S in SWI was due to sulfate reduction and iron reduction influenced greatly by hypoxia. Positive apparent fluxes were recorded indicating that the sediments release Fe-P-S to the overlying water. High positive correlations (r > 0.7) for DGT-labile Fe and DGT-labile P in sediments revealed that iron-bound P controlled the release of P at SWI during reductive dissolution. The low correlation between DGT-labile Fe and DGT-labile S (r < 0.4) disclosed the combative nature between sulfate reduction and iron reduction process. The low correlation occurred because of the co-precipitation between Fe and S, forming black materials such as monosulfide (FeS) and pyrite (FeS) in a hypoxic environment. The DIFS model showed the resupply ability (R-values) of P in sediments belonged to the partially sustained case with a steady state case of resupply at TB3 (Tc = 1088s, Kd = 1005.61 cm/g R = 0.72, K = 0.19 day) and TB4 (Tc = 712 s, Kd = 712.53 cm/g, R = 0.78, K = 0.46 day). The resupply rate belonged to the non-steady state case at TB1 (Tc = 10,990 s, Kd = 396.3 cm/g, R = 0.35, K = 0.07 day) and TB2 (Tc = 6097 s, Kd = 578.5 cm/g, R = 0.45, K = 0.10 day). The DGT-CID-PO-DIFS provided a deep insight on the mechanism of Fe-P-S and remobilization of P at SWI leading to Blackwater events and eutrophication.
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http://dx.doi.org/10.1016/j.scitotenv.2020.138204DOI Listing
July 2020

Mapping accumulative whole-brain activities during environmental enrichment with manganese-enhanced magnetic resonance imaging.

Neuroimage 2020 04 28;210:116588. Epub 2020 Jan 28.

Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, PR China; National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, PR China. Electronic address:

An enriched environment (EE) provides multi-dimensional stimuli to the brain. EE exposure for days to months induces functional and structural neuroplasticity. In this study, manganese-enhanced magnetic resonance imaging (MEMRI) was used to map the accumulative whole-brain activities associated with a 7-day EE exposure in freely-moving adult male mice, followed by c-Fos immunochemical assessments. Relative to the mice residing in a standard environment (SE), the mice subjected to EE treatment had significantly enhanced regional MEMRI signal intensities in the prefrontal cortex, somatosensory cortices, basal ganglia, amygdala, motor thalamus, lateral hypothalamus, ventral hippocampus and midbrain dopaminergic areas at the end of the 7-day exposure, likely attributing to enhanced Mn uptake/transport associated with brain activities at both the regional and macroscale network levels. Some of, but not all, the brain regions in the EE-treated mice showing enhanced MEMRI signal intensity had accompanying increases in c-Fos expression. The EE-treated mice were also found to have significantly increased overall amount of food consumption, decreased body weight gain and upregulated tyrosine hydroxylase (TH) expression in the midbrain dopaminergic areas. Taken together, these results demonstrated that the 7-day EE exposure was associated with elevated cumulative activities in the nigrostriatal, mesolimbic and corticostriatal circuits underpinning reward, motivation, cognition, motor control and appetite regulation. Such accumulative activities might have served as the substrate of EE-related neuroplasticity and the beneficial effects of EE treatment on neurological/psychiatric conditions including drug addiction, Parkinson's disease and eating disorder.
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http://dx.doi.org/10.1016/j.neuroimage.2020.116588DOI Listing
April 2020

Generation of Blastocyst-like Structures from Mouse Embryonic and Adult Cell Cultures.

Cell 2019 Oct;179(3):687-702.e18

Gene Expression Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA. Electronic address:

A single mouse blastomere from an embryo until the 8-cell stage can generate an entire blastocyst. Whether laboratory-cultured cells retain a similar generative capacity remains unknown. Starting from a single stem cell type, extended pluripotent stem (EPS) cells, we established a 3D differentiation system that enabled the generation of blastocyst-like structures (EPS-blastoids) through lineage segregation and self-organization. EPS-blastoids resembled blastocysts in morphology and cell-lineage allocation and recapitulated key morphogenetic events during preimplantation and early postimplantation development in vitro. Upon transfer, some EPS-blastoids underwent implantation, induced decidualization, and generated live, albeit disorganized, tissues in utero. Single-cell and bulk RNA-sequencing analysis revealed that EPS-blastoids contained all three blastocyst cell lineages and shared transcriptional similarity with natural blastocysts. We also provide proof of concept that EPS-blastoids can be generated from adult cells via cellular reprogramming. EPS-blastoids provide a unique platform for studying early embryogenesis and pave the way to creating viable synthetic embryos by using cultured cells.
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http://dx.doi.org/10.1016/j.cell.2019.09.029DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7359735PMC
October 2019

Repeated fluoxetine treatment induces long-lasting neurotrophic changes in the medial prefrontal cortex of adult rats.

Behav Brain Res 2019 06 5;365:114-124. Epub 2019 Mar 5.

Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, PR China; National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, PR China. Electronic address:

Fluoxetine (Flx), a selective serotonin reuptake inhibitor, is extensively used to treat mood and anxiety disorders. Previous animal studies have shown that early-life exposure to Flx results in long-lasting behavioral alterations and neuroplasticity in the hippocampus and cortex, which may persist into adulthood. It remains unclear whether repeated Flx treatment in normal adult animals can induce lasting neuroplasticity and behavioral alterations persisting long beyond the treatment period. In this study, young adult rats (about 9 weeks old) were treated with Flx (10 mg/kg body weight, twice daily) for 15 consecutive days, and the effects of Flx on medial prefrontal cortex (mPFC) neuroplasticity and mPFC-related behaviors were assessed 20 days after the last injection. It was observed that the mPFC of Flx-treated rats had significant increases in the number of 5-bromodeoxyuridine-positive (BrdU) cells, dendritic complexity/spine density in layer II/III pyramidal neurons, and brain-derived neurotrophic factor (BDNF)/tropomyosin receptor kinase B (TrkB) expression levels, as well as a significant decrease in the number of parvalbumin-positive (PV) interneurons. The Flx-treated rats exhibited higher motivation to explore new environments, evidenced by a significantly increased number of entries into the novel arm in the Y-maze test. However, they did not show any significant changes in the anhedonia and anxiety levels measured by sucrose preference and elevated plus maze tests respectively. In conclusion, repeated Flx treatment, with the paradigm used, induces long-lasting neuroplastic changes in the mPFC of normal adult rats; such changes and related behavioral manifestations may persist up to 20 days after the last dose.
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http://dx.doi.org/10.1016/j.bbr.2019.03.009DOI Listing
June 2019

Isolation and genome-wide characterization of cellular DNA:RNA triplex structures.

Nucleic Acids Res 2019 03;47(5):2306-2321

Division of Molecular Biology of the Cell II, German Cancer Research Center, DKFZ-ZMBH Alliance, Heidelberg, Germany.

RNA can directly bind to purine-rich DNA via Hoogsteen base pairing, forming a DNA:RNA triple helical structure that anchors the RNA to specific sequences and allows guiding of transcription regulators to distinct genomic loci. To unravel the prevalence of DNA:RNA triplexes in living cells, we have established a fast and cost-effective method that allows genome-wide mapping of DNA:RNA triplex interactions. In contrast to previous approaches applied for the identification of chromatin-associated RNAs, this method uses protein-free nucleic acids isolated from chromatin. High-throughput sequencing and computational analysis of DNA-associated RNA revealed a large set of RNAs which originate from non-coding and coding loci, including super-enhancers and repeat elements. Combined analysis of DNA-associated RNA and RNA-associated DNA identified genomic DNA:RNA triplex structures. The results suggest that triplex formation is a general mechanism of RNA-mediated target-site recognition, which has major impact on biological functions.
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http://dx.doi.org/10.1093/nar/gky1305DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6411930PMC
March 2019

Purification, characterization, antioxidant and moisture-preserving activities of polysaccharides from Rosa rugosa petals.

Int J Biol Macromol 2019 Mar 30;124:938-945. Epub 2018 Nov 30.

College of Pharmacology, Mudanjiang Medical University, Mudanjiang 157011, PR China. Electronic address:

The present study, we prepared polysaccharides from Rosa rugosa petals (RRPS) using hot-water extraction and purified the polysaccharides by chromatography to obtain RRPS-1 and RRPS-2. Preliminary structural features of RRPS were characterized by different instrumental methods, such as HPGPC, FT-IR, and GC analysis. The average molecular weights of RRPS-1 and RRPS-2 were 8.8 kDa and 443.8 kDa, respectively. Then, antioxidant and moisture-preserving activities of RRPS were determined in vitro. The analysis of antioxidant activities suggested that RRPS-2 had good potential for scavenging activity of radicals. We also found that the RRPS-2 has strong moisture-preserving activity in vitro. These results clearly indicated that RRPS-2 might have a good potential to be utilized in pharmaceutical, food and cosmetics industries.
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http://dx.doi.org/10.1016/j.ijbiomac.2018.11.275DOI Listing
March 2019

A crayfish Ras gene is involved in the defense against bacterial infection under high temperature.

Fish Shellfish Immunol 2019 Mar 28;86:608-617. Epub 2018 Nov 28.

College of Life Science, Qingdao Agricultural University, Qingdao, 266109, China. Electronic address:

Temperature is an important environmental factor influencing crustacean resistance to pathogen infection. However, the mechanism underlying immune regulation by temperature remains unclear in crustacean. Here, we report a Ras gene of crayfish (designated as PcRAS1) which is involved in immune regulation of crayfish under high temperature. PcRAS1 is induced by both high temperature and bacterial infection and the induction by bacterial infection is associated with temperature. Significant changes of PcRAS1 expression was observed at 32 °C and 24 °C after infection with Aeromonas hydrophila, but relative moderate alternation was found at 16 °C after challenged with A. hydrophila. PcRAS1 silencing significantly reduced crayfish survival from high temperature (32 °C and 24 °C) or bacterial infection at 32 °C, but there was no significant effect on survival from bacterial infection at 24 °C or 16 °C. Further analysis reveals that PO activity is reduced by high temperature or enhanced by bacterial infection. Moreover, both the decreased PO activity and the enhanced PO activity are affected by PcRAS1 expression. PcRAS1 silencing further reduces PO activity under high temperature and compromises the enhanced PO activity by bacterial infection. Lipid peroxidation (LPO) and total antioxidant capacity (TAC) are also involved in the responses to high temperature. LPO is enhanced by lower temperature. TAC is reduced by high temperature and TAC change resulting from high temperature is amplified by PcRAS1 silencing. These results collectively indicate that PcRAS1 is involved in immune regulation against bacterial infection mediated by temperature.
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http://dx.doi.org/10.1016/j.fsi.2018.11.062DOI Listing
March 2019

Well-controlled pleural effusion indicated pseudoprogression after immunotherapy in lung cancer: A case report.

Thorac Cancer 2018 09 6;9(9):1190-1193. Epub 2018 Jul 6.

Division of Thoracic Oncology, Cancer Center, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, China.

Squamous cancer (SqCC) of the lung has a poor prognosis. With the advent of immunotherapy, prognosis has tended to improve; however, pseudoprogression poses a challenge to the management of immunotherapy. Herein, we discuss the case of a 47-year-old heavy smoker with advanced SqCC. The patient had recurrent disease after initial successful control of the tumor by concurrent radiochemotherapy, together with ample pleural effusion. Pleural effusion was well controlled with systematic nivolumab and intra-thoracic recombinant endostatin; however with simultaneous deterioration of performance and tumor progression. Nivolumab was maintained with the addition of nab-paclitaxel. The combination soon led to a partial response and rapid improvement of the patient's performance. During treatment of this case, we advocated the early control of pleural effusion as an indicator for pseudoprogression. Our experience might be helpful to identify pseudoprogression for the clinical management of immunotherapy.
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http://dx.doi.org/10.1111/1759-7714.12799DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6119617PMC
September 2018

Mechanism and consequence of abnormal calcium homeostasis in Rett syndrome astrocytes.

Elife 2018 03 29;7. Epub 2018 Mar 29.

Waisman Center, University of Wisconsin-Madison, Madison, United States.

Astrocytes play an important role in Rett syndrome (RTT) disease progression. Although the non-cell-autonomous effect of RTT astrocytes on neurons was documented, cell-autonomous phenotypes and mechanisms within RTT astrocytes are not well understood. We report that spontaneous calcium activity is abnormal in RTT astrocytes in vitro, in situ, and in vivo. Such abnormal calcium activity is mediated by calcium overload in the endoplasmic reticulum caused by abnormal store operated calcium entry, which is in part dependent on elevated expression of TRPC4. Furthermore, the abnormal calcium activity leads to excessive activation of extrasynaptic NMDA receptors (eNMDARs) on neighboring neurons and increased network excitability in knockout mice. Finally, both the abnormal astrocytic calcium activity and the excessive activation of eNMDARs are caused by deletion in astrocytes in vivo. Our findings provide evidence that abnormal calcium homeostasis is a key cell-autonomous phenotype in RTT astrocytes, and reveal its mechanism and consequence.
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http://dx.doi.org/10.7554/eLife.33417DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5902163PMC
March 2018

Mitochondrial DNA Mutations Associated with Type 2 Diabetes Mellitus in Chinese Uyghur Population.

Sci Rep 2017 12 5;7(1):16989. Epub 2017 Dec 5.

CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, 100101, P.R. China.

A hospital-based case-control study was conducted to investigate potential association between mitochondrial DNA and Type 2 diabetes mellitus (T2DM) in Chinese Uyghur population. We sequenced mitochondrial DNA from 210 Uyghur individuals including 88 T2DM patients and 122 controls. Using haplogroup classification and association test, we found that haplogroup H (odds ratio [OR] = 1.40; 95% confidence interval [CI]: 1.20-1.64; P = 0.0005138) and D4 (odds ratio = 1.47; 95% CI: 1.22-1.77; P = 0.001064) were associated with an increased risk of T2DM in Chinese Uyghur population. Two markers of haplogroup D4 and H, MT-ATP8 m.8414 T > G (p.Leu17Phe) and m.2706 G > A encoding 16S rRNA in mitochondria, were predicted to affect the structure of MT-ATP8 and 16S RNA, respectively, and may be involved in the pathogenesis of T2DM. Our study provides a new clue for mitochondrial DNA in the etiology of T2DM in Chinese Uyghur population.
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http://dx.doi.org/10.1038/s41598-017-17086-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5717000PMC
December 2017

High Mobility Group Box 1 Protein Level as a Novel Biomarker for the Development of Peri-Implant Disease.

Sci Rep 2017 08 1;7(1):7027. Epub 2017 Aug 1.

Department of Stomatology, Jinan Central Hospital, Shandong University, Jinan, 250013, P.R. China.

Peri-implant disease is a chronic inflammation of the soft and hard tissues around a dental implant, resulting from bacterial infection. Recent evidence indicates that some pro-inflammatory cytokines and chemokines released by immunocytes are substantially responsible for the progress and consequence of inflammation. High mobility group box 1 (HMGB1) is released into the extracellular matrix and acts as a key pro-inflammatory factor during injury, necrosis and inflammation. A higher concentration of HMGB1 has been found in gingival crevicular fluid from inflammatory gingival tissue than from healthy sites. HMGB1 mRNA and protein are overexpressed in murine periodontal ligament fibroblasts stimulated with lipopolysaccharide (LPS) and IL-1β. Thus, this study sought to assess HMGB1 expression in peri-implant crevicular fluid (PICF) at each stage of peri-implant disease and to investigate the correlation between HMGB1 and peri-implant disease progress. The results demonstrated that the HMGB1 expression level in PICF is indicative of the progress of peri-implant disease and hence may be a useful diagnostic and prognostic biomarker for peri-implant tissue.
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http://dx.doi.org/10.1038/s41598-017-06937-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5539157PMC
August 2017

[Changes in ultrastructure and bone morphogenetic protein expression in reconstructed mandibular condylar cartilage under continuous mandibular advancement in adult rats].

Hua Xi Kou Qiang Yi Xue Za Zhi 2016 Dec;34(6):632-638

Dept. of Stomatology, Jinan Central Hospital Affiliated to Shandong University, Jinan 250013, China.

Objective: This study investigated the reconstructed mandibular condylar cartilage and the ultrastructural variations in mandibular condylar cartilage in adult rats as a result of mandibular advancement.

Methods: Thirty 9-week-old male Sprague-Dawley rats were randomly divided into experimental and control groups. Rats in the experimental group were subjected to mandibular advancement. Rats were sacrificed on days 3, 7, 14, 21, 30. Sections were cut from condyles, and bone morphogenetic protein-2 (BMP-2) expression in condylar cartilage was examined through immunohistochemical analysis. Condylar cartilage samples were harvested, and ultrastructural changes in these samples were observed under Micro-CT and transmission electron microscope.

Results: Compared with the control group, the experimental group obviously displayed cartilage hyperplasia in the middle and rear of the condyle. Moreover, the number of BMP-2-positive cells in condylar cartilage and the gray value gradually increased in the experimental group on day 7 of the intervention. Ultrastructural changes, such as karyopyknosis, reduced microfilaments around the nucleus, reduction in size or even disappearance of lipid droplets, swelling of endoplasmic reticulum compartments, broadened and increased extracellular matrix, were observed in the condylar hypertrophic chondrocytes. Micro-CT revealed that the trabecula and the newly formed bone gradually thickened.

Conclusions: Hypertrophic remodeling of the condylar cartilage and high BMP-2 expression are observed in adult rats as a result of continuous mandibular advancement.
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http://dx.doi.org/10.7518/hxkq.2016.06.016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7030868PMC
December 2016

CREB Signaling Is Involved in Rett Syndrome Pathogenesis.

J Neurosci 2017 03 7;37(13):3671-3685. Epub 2017 Mar 7.

Waisman Center,

Rett syndrome (RTT) is a debilitating neurodevelopmental disorder caused by mutations in the gene. To facilitate the study of cellular mechanisms in human cells, we established several human stem cell lines: human embryonic stem cell (hESC) line carrying the common T158M mutation ( ), hESC line expressing no MECP2 (), congenic pair of wild-type and mutant RTT patient-specific induced pluripotent stem cell (iPSC) line carrying the V247fs mutation (V247fs-WT and V247fs-MT), and iPSC line in which the V247fs mutation was corrected by CRISPR/Cas9-based genome editing (V247fs-MT-correction). Detailed analyses of forebrain neurons differentiated from these human stem cell lines revealed genotype-dependent quantitative phenotypes in neurite growth, dendritic complexity, and mitochondrial function. At the molecular level, we found a significant reduction in the level of CREB and phosphorylated CREB in forebrain neurons differentiated from , , and V247fs-MT stem cell lines. Importantly, overexpression of CREB or pharmacological activation of CREB signaling in those forebrain neurons rescued the phenotypes in neurite growth, dendritic complexity, and mitochondrial function. Finally, pharmacological activation of CREB in the female heterozygous mice rescued several behavioral defects. Together, our study establishes a robust platform for consistent quantitative evaluation of genotype-dependent RTT phenotypes, reveals a previously unappreciated role of CREB signaling in RTT pathogenesis, and identifies a potential therapeutic target for RTT. Our study establishes a robust human stem cell-based platform for consistent quantitative evaluation of genotype-dependent Rett syndrome (RTT) phenotypes at the cellular level. By providing the first evidence that enhancing cAMP response element binding protein signaling can alleviate RTT phenotypes both and , we reveal a previously unappreciated role of cAMP response element binding protein signaling in RTT pathogenesis, and identify a potential therapeutic target for RTT.
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http://dx.doi.org/10.1523/JNEUROSCI.3735-16.2017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5373141PMC
March 2017

Misregulation of Alternative Splicing in a Mouse Model of Rett Syndrome.

PLoS Genet 2016 06 28;12(6):e1006129. Epub 2016 Jun 28.

CMB Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America.

Mutations in the human MECP2 gene cause Rett syndrome (RTT), a severe neurodevelopmental disorder that predominantly affects girls. Despite decades of work, the molecular function of MeCP2 is not fully understood. Here we report a systematic identification of MeCP2-interacting proteins in the mouse brain. In addition to transcription regulators, we found that MeCP2 physically interacts with several modulators of RNA splicing, including LEDGF and DHX9. These interactions are disrupted by RTT causing mutations, suggesting that they may play a role in RTT pathogenesis. Consistent with the idea, deep RNA sequencing revealed misregulation of hundreds of splicing events in the cortex of Mecp2 knockout mice. To reveal the functional consequence of altered RNA splicing due to the loss of MeCP2, we focused on the regulation of the splicing of the flip/flop exon of Gria2 and other AMPAR genes. We found a significant splicing shift in the flip/flop exon toward the flop inclusion, leading to a faster decay in the AMPAR gated current and altered synaptic transmission. In summary, our study identified direct physical interaction between MeCP2 and splicing factors, a novel MeCP2 target gene, and established functional connection between a specific RNA splicing change and synaptic phenotypes in RTT mice. These results not only help our understanding of the molecular function of MeCP2, but also reveal potential drug targets for future therapies.
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http://dx.doi.org/10.1371/journal.pgen.1006129DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4924826PMC
June 2016

Truncated type IV pilin PilA(108) activates the intramembrane protease AlgW to cleave MucA and PilA(108) itself in vitro.

Arch Microbiol 2016 Nov 6;198(9):885-92. Epub 2016 Jun 6.

Institute of Hydrobiology, Chinese Academy of Sciences, 7 South Donghu Road, Wuchang District, Wuhan, 430072, China.

For alginate production in Pseudomonas aeruginosa, the intramembrane protease AlgW must be activated to cleave the periplasmic domain of anti-sigma factor MucA for release of the sequestered ECF sigma factor AlgU. Previously, we reported that three tandem point mutations in the pilA gene, resulting in a truncated type IV pilin termed PilA(108) with a C-terminal motif of phenylalanine-threonine-phenylalanine (FTF), induced mucoidy in strain PAO579. In this study, we purified PilA(108) protein and synthesized a peptide 'SGAGDITFTF' corresponding to C-terminus of PilA(108) and found they both caused the degradation of MucA by AlgW. Interestingly, AlgW could also cleave PilA(108) between alanine(62) and glycine(63) residues. Overexpression of the recombinant FTF motif-bearing MucE protein, originally a small periplasmic polypeptide with the C-terminal motif WVF, could induce mucoid conversion in the PAO1 strain. In all, our results provided a model of activation of AlgW by another protein ending with proper motifs. Our data suggest that in addition to MucA cleavage, AlgW may cleave other substrates.
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http://dx.doi.org/10.1007/s00203-016-1248-yDOI Listing
November 2016

Knockdown of ephrin receptor A7 suppresses the proliferation and metastasis of A549 human lung cancer cells.

Mol Med Rep 2016 Apr 18;13(4):3190-6. Epub 2016 Feb 18.

Department of Clinical Laboratory, Hongqi Hospital, Mudanjiang Medical University, Mudanjiang, Heilongjiang 157011, P.R. China.

Previous studies have demonstrated that ephrin (Eph) family receptor tyrosine kinases and ligands promote cancer growth, invasion and metastasis. In addition, it has been reported that Eph receptor A7 (EphA7) is transcriptionally activated in lung cancer; however, the effects of silencing EphA7 expression on the growth of lung cancer cells, and the underlying molecular mechanisms, have yet to be determined. Therefore, the present study aimed to investigate whether silencing EphA7 with small interfering (si)RNA could induce apoptosis in non‑small cell lung cancer (NSCLC) cells. Furthermore, the effects of siEphA7 on cell migration and invasion were evaluated using Transwell assays. The mechanisms underlying the effects of siEphA7 on the tumorigenic properties of A549 cells were also examined. The results of the present study demonstrated that transfection with siEphA7 inhibited the proliferation, migration and invasion of A549 cells. In addition, siEphA7 significantly increased the protein expression levels of B‑cell lymphoma 2 (Bcl‑2)‑associated X protein and caspase‑3, and decreased the protein expression levels of Bcl‑2, thus suggesting that siEphA7 was able to induce apoptosis via the intrinsic apoptotic pathway. In addition, the expression levels of phosphatase and tensin homolog (PTEN) were significantly upregulated, and the expression levels of total AKT were not altered, whereas the levels of phosphorylated‑AKT were reduced. These findings indicated that EphA7 may have an important role in the pathogenesis of NSCLC by regulating PTEN expression via the PTEN/AKT pathway. Silencing EphA7 may provide a novel approach for the treatment of NSCLC.
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http://dx.doi.org/10.3892/mmr.2016.4904DOI Listing
April 2016

Effects of intermediate metabolite carboxylic acids of TCA cycle on Microcystis with overproduction of phycocyanin.

Environ Sci Pollut Res Int 2015 Apr 24;22(7):5531-7. Epub 2014 Oct 24.

Institute of Hydrobiology, The Chinese Academy of Sciences and University of Chinese Academy of Sciences, Wuhan, 430072, China.

Toxic Microcystis species are the main bloom-forming cyanobacteria in freshwaters. It is imperative to develop efficient techniques to control these notorious harmful algal blooms (HABs). Here, we present a simple, efficient, and environmentally safe algicidal way to control Microcystis blooms, by using intermediate carboxylic acids from the tricarboxylic acid (TCA) cycle. The citric acid, alpha-ketoglutaric acid, succinic acid, fumaric acid, and malic acid all exhibited strong algicidal effects, and particularly succinic acid could cause the rapid lysis of Microcystis in a few hours. It is revealed that the Microcystis-lysing activity of succinic acid and other carboxylic acids was due to their strong acidic activity. Interestingly, the acid-lysed Microcystis cells released large amounts of phycocyanin, about 27-fold higher than those of the control. On the other hand, the transcription of mcyA and mcyD of the microcystin biosynthesis operon was not upregulated by addition of alpha-ketoglutaric acid and other carboxylic acids. Consider the environmental safety of intermediate carboxylic acids. We propose that administration of TCA cycle organic acids may not only provide an algicidal method with high efficiency and environmental safety but also serve as an applicable way to produce and extract phycocyanin from cyanobacterial biomass.
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http://dx.doi.org/10.1007/s11356-014-3730-xDOI Listing
April 2015

Studies on kinetics of water quality factors to establish water transparency model in Neijiang River, China.

J Environ Biol 2014 May;35(3):513-9

The basis for submerged plant restoration in surface water is to research the complicated dynamic mechanism of water transparency. In this paper, through the impact factor analysis of water transparency, the suspended sediment, dissolved organic matter, algae were determined as three main impactfactors for water transparency of Neijiang River in Eastern China. And the multiple regression equation of water transparency and sediment concentration, permanganate index, chlorophyll-a concentration was developed. Considering the complicated transport and transformation of suspended sediment, dissolved organic matter and algae, numerical model of them were developed respectively for simulating the dynamic process. Water transparency numerical model was finally developed by coupling the sediment, water quality, and algae model. These results showed that suspended sediment was a key factor influencing water transparency of Neijiang River, the influence of water quality indicated by chemical oxygen demand and algal concentration indicated by chlorophyll a were indeterminate when their concentrations were lower, the influence was more obvious when high concentrations are available, such three factors showed direct influence on water transparency.
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May 2014

Mutant astrocytes differentiated from Rett syndrome patients-specific iPSCs have adverse effects on wild-type neurons.

Hum Mol Genet 2014 Jun 12;23(11):2968-80. Epub 2014 Jan 12.

Genetics Training Program.

The disease mechanism of Rett syndrome (RTT) is not well understood. Studies in RTT mouse models have suggested a non-cell-autonomous role for astrocytes in RTT pathogenesis. However, it is not clear whether this is also true for human RTT astrocytes. To establish an in vitro human RTT model, we previously generated isogenic induced pluripotent stem cell (iPSC) lines from several RTT patients carrying different disease-causing mutations. Here, we show that these RTT iPSC lines can be efficiently differentiated into astroglial progenitors and glial fibrillary acidic protein-expressing (GFAP(+)) astrocytes that maintain isogenic status, that mutant RTT astrocytes carrying three different RTT mutations and their conditioned media have adverse effects on the morphology and function of wild-type neurons and that the glial effect on neuronal morphology is independent of the intrinsic neuronal deficit in mutant neurons. Moreover, we show that both insulin-like growth factor 1 (IGF-1) and GPE (a peptide containing the first 3 amino acids of IGF-1) are able to partially rescue the neuronal deficits caused by mutant RTT astrocytes. Our findings confirm the critical glial contribution to RTT pathology, reveal potential cellular targets of IGF-1 therapy and further validate patient-specific iPSCs and their derivatives as valuable tools to study RTT disease mechanism.
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http://dx.doi.org/10.1093/hmg/ddu008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4014193PMC
June 2014

Radiotherapy for gastric cancer: a systematic review and meta-analysis.

Tumour Biol 2014 Jan 9;35(1):387-96. Epub 2013 Aug 9.

Department of Medical Oncology, West China Hospital/ Laboratory of Signal Transduction and Molecular Targeted Therapy, State Key Laboratory of Biotherapy, Sichuan University, Chengdu, Sichuan Province, 610041, China,

There have been many trials trying to prove the benefit of radiotherapy for gastric cancer; however, the results were either inclusive or controversial. The purpose of the study was to elucidate the effect of radiotherapy on gastric cancer delivered as perioperative or palliative treatment. We conducted systematic searches for trials exploring the effect of radiotherapy on gastric cancer. In the subgroup of patients receiving preoperative radiotherapy for gastric cancer, a significant benefit was found on 10-year overall survival with a hazard ratio (HR) of 0.75 (95% confidence interval (CI), 0.61 to 0.91); however, the benefit on 5-year overall survival was not proven (HR, 0.68; 95%CI, 0.45 to 1.01). There are also no significant differences in resection rate and radical resection rate between group of patients receiving radiotherapy and control group with a relative risk (RR) of 1.06 (95%CI, 0.99 to 1.13) and 1.12 (95%CI 0.93 to 1.36), respectively. In the subgroup of patients receiving postoperative radiotherapy for gastric cancer, survival benefits were found on 3- and 5-year progression-free survival with HR of 0.69 (95%CI, 0.53 to 0.90) and HR of 0.70 (95%CI, 0.61 to 0.80), respectively. Survival benefits of adjuvant radiotherapy on 3- and 5-year progression-free survival were also found; nonetheless, there was no evidence of significant difference in 3-year overall survival (HR, 0.70; 95%CI, 0.61 to 1.01). The effect of radiotherapy on 5-year overall survival was also quite controversial. In short, gastric cancer patients could benefit from radiotherapy both in the form of preoperative radiotherapy and postoperative radiotherapy.
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http://dx.doi.org/10.1007/s13277-013-1054-yDOI Listing
January 2014

Novel split-luciferase-based genetically encoded biosensors for noninvasive visualization of Rho GTPases.

PLoS One 2013 16;8(4):e62230. Epub 2013 Apr 16.

Department of Medical Oncology, West China Hospital, Sichuan University, Chengdu, Sichuan, China.

Rho family GTPases are critical regulators of many important cellular processes and the dysregulation of their activities is implicated in a variety of human diseases including oncogenesis and propagation of malignancy. The traditional methods, such as "pull-down" or two-hybrid procedures, are poorly suited to dynamically evaluate the activity of Rho GTPases, especially in living mammalian cells. To provide a novel alternative approach to analyzing Rho GTPase-associated signaling pathways in vivo, we developed a series of bioluminescent biosensors based on the genetically engineered firefly luciferase. These split-luciferase-based biosensors enable non-invasive visualization and quantification of the activity of Rho GTPases in living subjects. The strategy is to reasonably split the gene of firefly luciferase protein into two inactive fragments and then respectively fuse the two fragments to Rho GTPase and the GTPase-binding domain (GBD) of the specific effector. Upon Rho GTPase interacting with the binding domain in a GTP-dependent manner, these two luciferase fragments are brought into close proximity, leading to luciferase reconstitution and photon production in the presence of the substrate. Using these bimolecular luminescence complementation (BiLC) biosensors, we successfully visualized and quantified the activities of the three best characterized Rho GTPases by measuring the luminescence in living cells. We also experimentally investigated the sensitivity of these Rho GTPase biosensors to upstream regulatory proteins and extracellular ligands without lysing cells and doing labor-intensive works. By virtue of the unique functional characteristics of bioluminescence imaging, the BiLC-based biosensors provide an enormous potential for in vivo imaging of Rho GTPase signaling pathways and high-throughput screening of therapeutic drugs targeted to Rho GTPases and (or) upstream molecules in the near future.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0062230PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3627919PMC
November 2013

Suppression of RND3 activity by AES downregulation promotes cancer cell proliferation and invasion.

Int J Mol Med 2013 May 27;31(5):1081-6. Epub 2013 Mar 27.

Laboratory of Signal Transduction and Molecular Targeted Therapy, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, P.R. China.

Amino-terminal enhancer of split (AES) is a member of the Groucho/TLE family. Although it has no DNA-binding site, AES can regulate transcriptional activity by interacting with transcriptional factors. Emerging evidence indicates that AES may play an important role in tumor metastasis, but the molecular mechanism is still poorly understood. In this study, we found that knockdown of AES by RNA interference (RNAi) downregulated RND3 expression at the mRNA and protein levels in MDA-MB-231 and HepG2, two cancer cell lines. Furthermore, luciferase assays showed that overexpression of AES significantly enhanced RND3 promoter activity. Moreover, inhibition of AES both in MDA-MB-231 and HepG2 cells by RNAi significantly promoted cell proliferation, cell cycle progression and invasion, consistent with the effects of RNAi-mediated RND3 knockdown in these cells. For the first time, data are presented showing that alteration of the malignant behavior of cancer cells by AES is related to RND3 regulation, and these findings also provide new insights into the mechanism of AES action in regulating tumor malignancy.
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http://dx.doi.org/10.3892/ijmm.2013.1321DOI Listing
May 2013

Effects of lipoprotein lipase gene variations, a high-carbohydrate low-fat diet, and gender on serum lipid profiles in healthy Chinese Han youth.

Biosci Trends 2011 ;5(5):198-204

Department of Biochemistry and Molecular Biology, West China School of Preclinical and Forensic Medicine and State Key Laboratory of Oral Diseases, Sichuan University, Chengdu, China.

A high-carbohydrate low-fat (HC/LF) diet and lipoprotein lipase gene (LPL) Ser447Stop and Hind III polymorphisms have separately been found to be associated with triacylglycerol (TG) and high density lipoprotein cholesterol (HDL-C). This study sought to test the effects of LPL polymorphisms and an HC/LF diet on the serum lipid profile of Chinese with a lower incidence of coronary artery disease (CAD) consuming a diet with less fat and more carbohydrates. Fifty-six healthy subjects (22.89 ± 1.80 years) were given a control diet of 30.1% fat and 54.1% carbohydrates for 7 days, followed by an HC/LF diet of 13.8% fat and 70.1% carbohydrate for 6 days; there were no changes in the fatty acid composition or restrictions on total energy. Serum lipid profiles at baseline, before and after the HC/LF diet, and LPL polymorphisms were analyzed. After 6 days of the HC/LF diet, TG and the homeostasis model assessment of insulin resistance (HOMAIR) index were found to increase only in females with S447S. No decrease in HDL-C was noted. In subjects with Hind III polymorphism, increased TG was found in all females but not in males. Increased HDL-C, together with apolipoprotein (apo) AI, was found in male H- carriers but not in males with H+/H+ and females. In conclusion, LPL Ser447Stop and Hind III polymorphisms modified the effects of an HC/LF diet on the serum lipid profiles of a young Chinese population in different ways. Effective strategies for dietary interventions targeted at younger populations should take into account the interplay between genetic polymorphisms, diet, and gender.
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http://dx.doi.org/10.5582/bst.2011.v5.5.198DOI Listing
May 2012

Natural variation in host-specific nodulation of pea is associated with a haplotype of the SYM37 LysM-type receptor-like kinase.

Mol Plant Microbe Interact 2011 Nov;24(11):1396-403

Northwest A & F University, Yangling, China.

Rhizobium leguminosarum bv. viciae, which nodulates pea and vetch, makes a mixture of secreted nodulation signals (Nod factors) carrying either a C18:4 or a C18:1 N-linked acyl chain. Mutation of nodE blocks the formation of the C18:4 acyl chain, and nodE mutants, which produce only C18:1-containing Nod factors, are less efficient at nodulating pea. However, there is significant natural variation in the levels of nodulation of different pea cultivars by a nodE mutant of R. leguminosarum bv. viciae. Using recombinant inbred lines from two pea cultivars, one which nodulated relatively well and one very poorly by the nodE mutant, we mapped the nodE-dependent nodulation phenotype to a locus on pea linkage group I. This was close to Sym37 and PsK1, predicted to encode LysM-domain Nod-factor receptor-like proteins; the Sym2 locus that confers Nod-factor-specific nodulation is also in this region. We confirmed the map location using an introgression line carrying this region. Our data indicate that the nodE-dependent nodulation is not determined by the Sym2 locus. We identified several pea lines that are nodulated very poorly by the R. leguminosarum bv. viciae nodE mutant, sequenced the DNA of the predicted LysM-receptor domains of Sym37 and PsK1, and compared the sequences with those derived from pea cultivars that were relatively well nodulated by the nodE mutant. This revealed that one haplotype (encoding six conserved polymorphisms) of Sym37 is associated with very poor nodulation by the nodE mutant. There was no such correlation with polymorphisms at the PsK1 locus. We conclude that the natural variation in nodE-dependent nodulation in pea is most probably determined by the Sym37 haplotype.
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http://dx.doi.org/10.1094/MPMI-01-11-0004DOI Listing
November 2011