The Experts below are selected from a list of 468 Experts worldwide ranked by ideXlab platform
Xiaobing Wu - One of the best experts on this subject based on the ideXlab platform.
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AFLP Analysis of genetic variation on captive-bred Chinese Alligators: an application to select individuals for release
Zoo Biology, 2020Co-Authors: Xiaobing Wu, Zhigang Jiang, Changming Gu, Yiyang Wang, Chaoling WangAbstract:The Chinese Alligator (Alligator sinensis) is a critically endangered species in China. Wild populations of Chinese Alligator are on the edge of extinction. Through a release program, some captive-bred Alligators will be selected and released into the wild to supplement and renew natural populations. The purpose of this study was to investigate the genetic variation of captive-bred Chinese Alligators by AFLP markers and to select individuals with maximally different genetic backgrounds for release. Forty-three captive-bred Alligators of the second filial generation from the Anhui Research Center for Chinese Alligator Reproduction (ARCCAR) were surveyed using four primer combinations, yielding 117 AFLP markers. According to AFLP fingerprints, six samples had distinctly different band patterns compared to other samples. When the six samples were removed from the analysis, there were 19 monomorphic loci and 98 polymorphic loci yielding 84% polymorphic loci. Moreover, the genetic similarity (GS) among 37 samples varied from 0.13–0.97, and the average was 0.7503±0.0064 standard error (SE). When the six samples were included, the GS value among the 43 samples declined and varied from 0.06–0.97, and the average was 0.6523±0.0079 SE. Based on a cluster analysis using UPGMA, a dendrogram of the 43 Alligators was constructed. According to the cluster analysis and gender of the 43 samples, eight Chinese Alligators with very different genetic backgrounds were selected and suggested for release with two groups in the future. Zoo Biol 0:1–12, 2006. © 2006 Wiley-Liss, Inc.
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Acoustic signals of Chinese Alligators (Alligator sinensis): social communication.
The Journal of the Acoustical Society of America, 2020Co-Authors: Xianyan Wang, Xiaobing Wu, Renping Wang, Ding Wang, Chaolin WangAbstract:This paper reports the first systematic study of acoustic signals during social interactions of the Chinese Alligator (Alligator sinensis). Sound pressure level (SPL) measurements revealed that Chinese Alligators have an elaborate acoustic communication system with both long-distance signal-bellowing-and short-distance signals that include tooting, bubble blowing, hissing, mooing, head slapping and whining. Bellows have high SPL and appear to play an important role in the Alligator's long range intercommunion. Sounds characterized by low SPL are short-distance signals used when Alligators are in close spatial proximity to one another. The signal spectrographic analysis showed that the acoustic signals of Chinese Alligators have a very low dominant frequency, less than 500 Hz. These frequencies are consistent with adaptation to a habitat with high density vegetation. Low dominant frequency sound attenuates less and could therefore cover a larger spatial range by diffraction in a densely vegetated environment relative to a higher dominant frequency sound.
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cloning characterisation and expression profile of kisspeptin1 and the kisspeptin1 receptor in the hypothalamic pituitary ovarian axis of Chinese Alligator Alligator sinensis during the reproductive cycle
Reproduction Fertility and Development, 2020Co-Authors: Yongkang Zhou, Ruidong Zhang, Ali Izaz, Renping Wang, Shulong Duan, Xiaobing WuAbstract:Kisspeptin1 (Kiss1), a product of the Kiss1 gene, plays an important role in the regulation of reproduction in vertebrates by activating the Kiss1 receptor (Kiss1R) and its coexpression with gonadotrophin-releasing hormone (GnRH) in GnRH neurons. The purpose of this study was to clone the Kiss1 and Kiss1R genes found in the brain of Alligator sinensis and to explore their relationship with reproduction. The full-length cDNA of Kiss1 is 816bp, the open reading frame (ORF) is 417bp and the gene encodes a 138-amino acid precursor protein. The full-length cDNA of Kiss1R is 2348bp, the ORF is 1086bp and the gene encodes a 361-amino acid protein. Quantitative polymerase chain reaction showed that, except for Kiss1R expression in the hypothalamus, the expression of Kiss1 and Kiss1Rduring the reproductive period of A. sinensis was higher than that in the hypothalamus, pituitary gland and ovary during the hibernation period. The changes in GnRH2 mRNA in the hypothalamus were similar to those of GnRH1 and peaked during the reproductive period. This study confirms the existence of Kiss1 and Kiss1R in A. sinensis and the findings strongly suggest that Kiss1 and Kiss1R may participate in the regulation of GnRH secretion in the hypothalamus of Alligators during the reproductive period. Furthermore, this is the first report of the full-length cDNA sequences of Kiss1 and Kiss1R in reptiles.
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historical population decline and habitat loss in a critically endangered species the Chinese Alligator Alligator sinensis
Global Ecology and Conservation, 2019Co-Authors: Huan Wang, Shulong Duan, Mingsheng Wang, Jihui Zhang, Huabin Zhang, Baowei Zhang, Xiaobing WuAbstract:Abstract Habitat loss and degradation are among the leading causes of local extinctions, so it is crucially important to preserve and restore the remaining critical habitat increasingly critical to conserve biodiversity. However, mechanisms driving species extinction often begin with habitat loss and seldom are well understood, which is greatly limits our ability to mitigate their impacts. The Chinese Alligator ( Alligator sinensis ) is a critically endangered crocodilian, which is narrowly distributed in very small six regions of Anhui province, China. In the present study, we used 9 nuclear microsatellite loci genotyped across the taxon's distribution area to investigate genetic variation and population demography in A. sinensis . The Chinese Alligator showed unusually low levels of genetic diversity ( N a, 5.44; N e, 1.97; H e, 0.47) based on 793 individuals. Msvar analyses found recent signals of population decline reflecting a bottleneck (an approximately 9-fold decrease) about 25,000 years ago. Ecological niche modelling has shown that the habitat area has declined (about 8–15 fold) for A. sinensis when compared with that under different historical climatic conditions. Our results indicated that population decline and habitat loss in critically endangered Chinese Alligators may have acted as intrinsic and extrinsic factors that have impacted the current status of A. sinensis . In addition, these two unfavorable factors may have also directly contributed to a reduction in the genetic diversity of A. sinensis .
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molecular cloning of androgen receptor and gene expression of sex steroid hormone receptors in the brain of newborn Chinese Alligator Alligator sinensis
Gene, 2018Co-Authors: Yongkang Zhou, Ruidong Zhang, Ying Zhang, Mengjuan Wu, Ali Izaz, Renping Wang, Xiaobing WuAbstract:Abstract Sex steroid hormones play an important role in mediating physiological responses and developmental processes through their receptors across all vertebrates. Chinese Alligator (Alligator sinensis) is a critically endangered reptile species unique to China. In this study, we have cloned one of the sex steroid hormone receptor genes, androgen receptor (AR) from the brain of Chinese Alligator for the first time. The full-length AR cDNA is 2717 bp in length with an open reading frame (ORF) encoding 722 amino acids. Amino acid alignment analyses indicated that the ARs exhibit highly conserved functional domains. Especially, the P-box and D-box, which are essential to ensure that receptor binding to the androgen response elements, are completely conserved in selected species. Using the quantitative real-time PCR (qPCR), the spatial expression of four receptor mRNAs in all newborn brain tissues and temporal expression of them in the cerebrum during the embryonic development in Chinese Alligators were investigated. The results of qPCR showed ubiquitous expression of the four receptor mRNAs in all newborn brain tissues examined and significant changes in the expression levels of these receptor mRNAs in the embryonic development. These results suggest that sex steroid hormones might play an important role in the regulation of complex neuroendocrine activities in newborn Chinese Alligator. Furthermore, these data provide an important foundation for further studies on endocrinology and molecular biology of non-mammalian sex steroid hormone receptors.
Shengguo Fang - One of the best experts on this subject based on the ideXlab platform.
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metagenomics reveals seasonal functional adaptation of the gut microbiome to host feeding and fasting in the Chinese Alligator
Frontiers in Microbiology, 2019Co-Authors: Keyi Tang, Zhenwei Wang, Shengguo FangAbstract:Hibernator gut microbiomes vary seasonally with host physiology and food availability, but their functional potential and host–microbial interactions have not been well characterized. As a natural hibernator, the Chinese Alligator (Alligator sinensis) is an ideal and intriguing model to investigate changes in microbial community structure and function caused by hibernation. In this study, we used 16S rRNA profiling and metagenomic analysis to compare the microbiome composition, diversity, and functional capacity in the gut of hibernating versus active Chinese Alligators. Our results show that gut microbial communities undergo seasonal restructuring in response to seasonal cycles of feeding and fasting in the Chinese Alligator, but this animal harbors a core gut microbial community primarily dominated by Proteobacteria, Fusobacteria, Bacteroidetes and Firmicutes across the gut regions. During hibernation, there is an increase in the abundance of bacterial taxa (e.g., Bacteroidetes) that can degrade and utilize host mucin glycans, which allows adaptation to winter fasting. This is accompanied by the enrichment of mucin oligosaccharide-degrading enzyme and carbohydrate-active enzyme families. In contrast, during the active phase (feeding), active Chinese Alligators exhibit a carnivore gut microbiome dominated by Fusobacteria, and there is an increase in the relative abundance of bacteria (e.g., Cetobacterium somerae) with known proteolytic and amino acids-fermentating functions that improve host protein-rich food digestion efficiency. In addition, seasonal variations in the expression of β-defensins play a protective role in intestinal immunity. These findings provide insights into the functional adaptations of host–gut microbe symbioses to seasonal dietary shifts to maintain gut homeostasis and health, especially in extreme physiological states.
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a crucial role of paralogous β defensin genes in the Chinese Alligator innate immune system revealed by the first determination of a crocodilia defensin cluster
Developmental and Comparative Immunology, 2018Co-Authors: Keyi Tang, Xin Wang, Shengguo FangAbstract:Abstract The β-defensin, one of the a nti m icrobial p eptides (AMPs), is a significant component of the innate immune with a broad range of antimicrobial activities. Differing from the widely-studied mammals and birds, limited information about β-defensins has been reported in reptiles, especially in crocodilians. As a same ancient species as dinosaurs and the most endangered species of 23 crocodilians, the survival of Chinese Alligator (Alligator sinensis) means a powerful immune system and possible involvement of AMPs in its immune resistance. In this study, we identified 20 novel A lligator s inensis β - d efensin genes (AsBDs) from a 390 kb region using bioinformatic and experimental approaches, and successfully distinguished six orthologous AsBDs to birds and nine paralogous AsBDs undergoing gene duplication events. The amino acid alignment shows that the AsBD paralogs, like α-defensins, encode a significantly longer pro-piece comparing with the orthologs. The calculation of non-synonymous (dN) and synonymous (dS) substitutions in the mature peptide reveals that the AsBD paralogs experience a significantly higher selective pressure (dN/dS) than the orthologs, but a similar evolutionary force to α-defensins. The gene expression result indicates that the AsBD paralogs have a significantly higher expression level than the orthologos in gastrointestinal tract where the host is vulnerable to enteric pathogenic bacteria, as observed in α-defensins. These three pieces of evidence demonstrate that the AsBD paralogs do play an important role in maintaining long-term survival of this endangered reptile. Thus, this survey of AsBDs on the genomic structure, evolutionary characteristics, and expression pattern provides a genetic and immunological foundation for further investigating their antimicrobial function and alternative antibiotics potentiality.
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effects of population bottleneck and balancing selection on the Chinese Alligator are revealed by locus specific characterization of mhc genes
Scientific Reports, 2017Co-Authors: Teng Zhai, Haiqiong Yang, Ruican Zhang, Liming Fang, Guoheng Zhong, Shengguo FangAbstract:Chinese Alligator (Alligator sinensis) is an endangered freshwater crocodilian endemic to China, which experienced a severe bottleneck about 30 years ago. In this study, we developed locus-specific primers to investigate the polymorphism of 3 major histocompatibility complex (MHC) loci in 3 Chinese Alligator populations, in combination with 6 neutral microsatellite markers as a contrast. We found the genetic trace for the bottleneck effect on the endangered Chinese Alligator: the low allelic diversity (2 alleles at each locus), the low nucleotide substitution rate (no more than 0.009) at all sites, the deviation from Hardy-Weinberg Equilibrium/heterozygote deficiency, and the significant Tajima’s D values, indicating the MHC class I and class II loci being at different stages of bottleneck. We also obtained 3 pieces of evidence for balancing selection on this severely bottlenecked reptile: an obvious excess of nonsynonymous substitutions over synonymous at the antigen-binding positions, the mean synonymous substitution rate of MHC exons significantly higher than mean nucleotide substitution rate of introns, and the differentiation coefficient F ST of MHC loci significantly lower than that of microsatellite loci. Consequently, we emphasize that the Chinese Alligator holds a pretty low adaptive ability and requires scientific conservation strategies to ensure the long-term population development.
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the sex ratio of wild Chinese Alligators Alligator sinensis
Current Zoology, 2013Co-Authors: Lan Zhao, Liming Fang, Haiqiong Yang, Shengguo FangAbstract:The Chinese Alligator Alligator sinensis is one of the most endangered crocodilian species, and typically exhibits temperature-dependent sex determination. It is extremely important to clarify the sex structure of Chinese Alligators to implement recovery projects successfully. However, the sex ratio of wild Chinese Alligators remains unknown. In this study, we collected 28 years of sex ratio data from Chinese Alligators residing in the natural and artificial habitats of Changxing Nature Reserve, China, and examined the differences in the sex ratio dynamics between these two populations. We observed that the sex ratio of wild Chinese Alligators is 1 male to 4.507 females, which was significantly lower compared to that of the captive population (1 to 2.040; P 0.05). Overall, this study indicates that the stabilized fe- male-biased sex ratio of Changxing Chinese Alligators might result from selection pressure caused by local mate competition and major inbreeding (Current Zoology 59 (6): 725-731, 2013).
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a bacterial artificial chromosome library for the Chinese Alligator Alligator sinensis
Gene, 2012Co-Authors: Ke He, Qing Ye, Hui Chen, Shengguo FangAbstract:Abstract Chinese Alligator (Alligator sinensis) is a rare and endangered species endemic to China. To better understand genetic details of the Chinese Alligator genomic structure, a highly redundant bacterial artificial chromosome (BAC) library was constructed. This library consists of 216,238 clones with an average insert size of about 90 kb, indicating that the library contains 6.8-fold genome equivalents. Subsequently, we constructed a 516 kb contig map for the Chinese Alligator olfactory receptor (OR) genes, which spans nine BAC clones, and subjected the BACs to full sequencing. The sequence analysis revealed that this contig contained 16 OR functional genes and meanwhile demonstrated that the nine BACs, which constituted the contig, overlapped correctly, proving the usability of this genome library. As a result, this BAC library could provide a useful platform for physical mapping, genome sequencing or complex analysis of targeted genomic regions for this rare species.
Yongkang Zhou - One of the best experts on this subject based on the ideXlab platform.
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cloning characterisation and expression profile of kisspeptin1 and the kisspeptin1 receptor in the hypothalamic pituitary ovarian axis of Chinese Alligator Alligator sinensis during the reproductive cycle
Reproduction Fertility and Development, 2020Co-Authors: Yongkang Zhou, Ruidong Zhang, Ali Izaz, Renping Wang, Shulong Duan, Xiaobing WuAbstract:Kisspeptin1 (Kiss1), a product of the Kiss1 gene, plays an important role in the regulation of reproduction in vertebrates by activating the Kiss1 receptor (Kiss1R) and its coexpression with gonadotrophin-releasing hormone (GnRH) in GnRH neurons. The purpose of this study was to clone the Kiss1 and Kiss1R genes found in the brain of Alligator sinensis and to explore their relationship with reproduction. The full-length cDNA of Kiss1 is 816bp, the open reading frame (ORF) is 417bp and the gene encodes a 138-amino acid precursor protein. The full-length cDNA of Kiss1R is 2348bp, the ORF is 1086bp and the gene encodes a 361-amino acid protein. Quantitative polymerase chain reaction showed that, except for Kiss1R expression in the hypothalamus, the expression of Kiss1 and Kiss1Rduring the reproductive period of A. sinensis was higher than that in the hypothalamus, pituitary gland and ovary during the hibernation period. The changes in GnRH2 mRNA in the hypothalamus were similar to those of GnRH1 and peaked during the reproductive period. This study confirms the existence of Kiss1 and Kiss1R in A. sinensis and the findings strongly suggest that Kiss1 and Kiss1R may participate in the regulation of GnRH secretion in the hypothalamus of Alligators during the reproductive period. Furthermore, this is the first report of the full-length cDNA sequences of Kiss1 and Kiss1R in reptiles.
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cytochemical patterns of the peripheral blood cells in Chinese Alligator Alligator sinensis
Tissue & Cell, 2018Co-Authors: Xianxian Chen, Jing Wang, Fei Peng, En Li, Yongkang Zhou, Shengzhou ZhangAbstract:Abstract The Chinese Alligator ( Alligator sinensis ) is an endemic rare crocodilian species in China. In this study, we investigated the cytochemical patterns of peripheral blood cells in Chinese Alligators for the first time by a range of cytochemical staining techniques including periodic acid-Schiff(PAS), sudan black B(SBB), peroxidase(POX), alkaline phosphatase(AKP), acid phosphatase(ACP), chloroacetic acid AS-D naphthol esterase(AS-D) and α-naphthol acetate esterase(α-NAE) staining. Erythrocytes were positive for PAS, and negative for all the other staining; heterophils were strongly positive for SBB, POX, ACP, AKP, AS-D and α-NAE, while weakly positive for PAS staining; eosinophils were strongly positive for PAS, POX, AKP, ACP and AS-D, and weakly positive for SBB and α-NAE staining; basophils were strongly positive for PAS, positive for POX, ACP, AKP and α-NAE, and weakly positive for AS-D, while negative for SBB staining; monocytes were weakly positive for PAS, ACP, AKP and α-NAE, while negative for SBB, POX and AS-D staining; lymphocytes were weakly positive for PAS and α-NAE, negative for all the other staining; thrombocytes were weakly positive for PAS, and negative for all the other staining. Our results add up knowledge about Chinese Alligator blood cells.
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molecular cloning of androgen receptor and gene expression of sex steroid hormone receptors in the brain of newborn Chinese Alligator Alligator sinensis
Gene, 2018Co-Authors: Yongkang Zhou, Ruidong Zhang, Ying Zhang, Mengjuan Wu, Ali Izaz, Renping Wang, Xiaobing WuAbstract:Abstract Sex steroid hormones play an important role in mediating physiological responses and developmental processes through their receptors across all vertebrates. Chinese Alligator (Alligator sinensis) is a critically endangered reptile species unique to China. In this study, we have cloned one of the sex steroid hormone receptor genes, androgen receptor (AR) from the brain of Chinese Alligator for the first time. The full-length AR cDNA is 2717 bp in length with an open reading frame (ORF) encoding 722 amino acids. Amino acid alignment analyses indicated that the ARs exhibit highly conserved functional domains. Especially, the P-box and D-box, which are essential to ensure that receptor binding to the androgen response elements, are completely conserved in selected species. Using the quantitative real-time PCR (qPCR), the spatial expression of four receptor mRNAs in all newborn brain tissues and temporal expression of them in the cerebrum during the embryonic development in Chinese Alligators were investigated. The results of qPCR showed ubiquitous expression of the four receptor mRNAs in all newborn brain tissues examined and significant changes in the expression levels of these receptor mRNAs in the embryonic development. These results suggest that sex steroid hormones might play an important role in the regulation of complex neuroendocrine activities in newborn Chinese Alligator. Furthermore, these data provide an important foundation for further studies on endocrinology and molecular biology of non-mammalian sex steroid hormone receptors.
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insights into the seasonal adaptive mechanisms of Chinese Alligators Alligator sinensis from transcriptomic analyses
Australian Journal of Zoology, 2018Co-Authors: Fang Zhang, Yongkang Zhou, En Li, Rong Wu, Xiaobing WuAbstract:The Chinese Alligator (Alligator sinensis) is an endemic and rare species in China, and is considered to be one of the most endangered vertebrates in the world. It is known to hibernate, an energy-saving strategy against cold temperatures and food deprivation. Changes in gene expression during hibernation remain largely unknown. To understand these complex seasonal adaptive mechanisms, we performed a comprehensive survey of differential gene expression in heart, skeletal muscle, and kidney of hibernating and active Chinese Alligators using RNA-Sequencing. In total, we identified 4780 genes differentially expressed between the active and hibernating periods. GO and KEGG pathway analysis indicated the likely role of these differentially expressed genes (DEGs). The upregulated DEGs in the active Chinese Alligator, CSRP3, MYG and PCKGC, may maintain heart and skeletal muscle contraction, transport and storage of oxygen, and enhance the body’s metabolism, respectively. The upregulated DEGs in the dormant Chinese Alligator, ADIPO, CIRBP and TMM27, may improve insulin sensitivity and glucose/lipid metabolism, protect cells against harmful effects of cold temperature and hypoxia, regulate amino acid transport and uptake, and stimulate the proliferation of islet cells and the secretion of insulin. These results provide a foundation for understanding the molecular mechanisms of the seasonal adaptation required for hibernation in Chinese Alligators, as well as effective information for other non-model organisms research.
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hematology and serum biochemistry parameters of captive Chinese Alligators Alligator sinensis during the active and hibernating periods
Tissue & Cell, 2018Co-Authors: Fei Peng, Xianxian Chen, En Li, Yongkang Zhou, Ting Meng, Shengzhou ZhangAbstract:Abstract The Chinese Alligator Alligator sinensis is an endangered freshwater crocodilian species endemic to China. Hematology and serum biochemistry reference range are useful in the assessment and management of animal health condition. In this study, a total of 74 Chinese Alligators (30 males and 44 females) were examined to establish reference range values of hematology and serum biochemistry parameters during the active and hibernating periods. We measured and analyzed 9 hematology and 21 serum biochemistry parameters including 4 serum electrolyte parameters, and described the morphology of different types of blood cells. No statistical differences between the sexes were found for hematology parameter, while significant differences were noted for some serum biochemistry parameters, with males having greater alkaline phosphatase activity level and lower globulin concentration value than females. There were some significant differences between the two different periods with Alligators during the active period possessing lower values for mean corpuscular volume, mean corpuscular hemoglobin, total bilirubin and creatine kinase, but higher values for red blood cell and white blood cell counts, monocyte percentage, aspartate aminotransferase, a-amylase, blood urea nitrogen, creatinine, triglycerides, and cholesterol. These baseline data were essential for health condition evaluation and disease diagnosis of this endangered species.
Renping Wang - One of the best experts on this subject based on the ideXlab platform.
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Acoustic signals of Chinese Alligators (Alligator sinensis): social communication.
The Journal of the Acoustical Society of America, 2020Co-Authors: Xianyan Wang, Xiaobing Wu, Renping Wang, Ding Wang, Chaolin WangAbstract:This paper reports the first systematic study of acoustic signals during social interactions of the Chinese Alligator (Alligator sinensis). Sound pressure level (SPL) measurements revealed that Chinese Alligators have an elaborate acoustic communication system with both long-distance signal-bellowing-and short-distance signals that include tooting, bubble blowing, hissing, mooing, head slapping and whining. Bellows have high SPL and appear to play an important role in the Alligator's long range intercommunion. Sounds characterized by low SPL are short-distance signals used when Alligators are in close spatial proximity to one another. The signal spectrographic analysis showed that the acoustic signals of Chinese Alligators have a very low dominant frequency, less than 500 Hz. These frequencies are consistent with adaptation to a habitat with high density vegetation. Low dominant frequency sound attenuates less and could therefore cover a larger spatial range by diffraction in a densely vegetated environment relative to a higher dominant frequency sound.
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cloning characterisation and expression profile of kisspeptin1 and the kisspeptin1 receptor in the hypothalamic pituitary ovarian axis of Chinese Alligator Alligator sinensis during the reproductive cycle
Reproduction Fertility and Development, 2020Co-Authors: Yongkang Zhou, Ruidong Zhang, Ali Izaz, Renping Wang, Shulong Duan, Xiaobing WuAbstract:Kisspeptin1 (Kiss1), a product of the Kiss1 gene, plays an important role in the regulation of reproduction in vertebrates by activating the Kiss1 receptor (Kiss1R) and its coexpression with gonadotrophin-releasing hormone (GnRH) in GnRH neurons. The purpose of this study was to clone the Kiss1 and Kiss1R genes found in the brain of Alligator sinensis and to explore their relationship with reproduction. The full-length cDNA of Kiss1 is 816bp, the open reading frame (ORF) is 417bp and the gene encodes a 138-amino acid precursor protein. The full-length cDNA of Kiss1R is 2348bp, the ORF is 1086bp and the gene encodes a 361-amino acid protein. Quantitative polymerase chain reaction showed that, except for Kiss1R expression in the hypothalamus, the expression of Kiss1 and Kiss1Rduring the reproductive period of A. sinensis was higher than that in the hypothalamus, pituitary gland and ovary during the hibernation period. The changes in GnRH2 mRNA in the hypothalamus were similar to those of GnRH1 and peaked during the reproductive period. This study confirms the existence of Kiss1 and Kiss1R in A. sinensis and the findings strongly suggest that Kiss1 and Kiss1R may participate in the regulation of GnRH secretion in the hypothalamus of Alligators during the reproductive period. Furthermore, this is the first report of the full-length cDNA sequences of Kiss1 and Kiss1R in reptiles.
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molecular cloning of androgen receptor and gene expression of sex steroid hormone receptors in the brain of newborn Chinese Alligator Alligator sinensis
Gene, 2018Co-Authors: Yongkang Zhou, Ruidong Zhang, Ying Zhang, Mengjuan Wu, Ali Izaz, Renping Wang, Xiaobing WuAbstract:Abstract Sex steroid hormones play an important role in mediating physiological responses and developmental processes through their receptors across all vertebrates. Chinese Alligator (Alligator sinensis) is a critically endangered reptile species unique to China. In this study, we have cloned one of the sex steroid hormone receptor genes, androgen receptor (AR) from the brain of Chinese Alligator for the first time. The full-length AR cDNA is 2717 bp in length with an open reading frame (ORF) encoding 722 amino acids. Amino acid alignment analyses indicated that the ARs exhibit highly conserved functional domains. Especially, the P-box and D-box, which are essential to ensure that receptor binding to the androgen response elements, are completely conserved in selected species. Using the quantitative real-time PCR (qPCR), the spatial expression of four receptor mRNAs in all newborn brain tissues and temporal expression of them in the cerebrum during the embryonic development in Chinese Alligators were investigated. The results of qPCR showed ubiquitous expression of the four receptor mRNAs in all newborn brain tissues examined and significant changes in the expression levels of these receptor mRNAs in the embryonic development. These results suggest that sex steroid hormones might play an important role in the regulation of complex neuroendocrine activities in newborn Chinese Alligator. Furthermore, these data provide an important foundation for further studies on endocrinology and molecular biology of non-mammalian sex steroid hormone receptors.
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analysis of tcrβ and tcrγ genes in Chinese Alligator provides insights into the evolution of tcr genes in jawed vertebrates
Developmental and Comparative Immunology, 2018Co-Authors: Xifeng Wang, Chaolin Wang, Renping Wang, Peng Wang, Cuncun Ke, Di Yu, Kongpan Li, Yaofeng Zhao, Xin ZhouAbstract:Abstract All jawed vertebrates have four T cell receptor (TCR) chains that are expressed by thymus-derived lymphocytes and play a major role in animal immune defence. However, few studies have investigated the TCR chains of crocodilians compared with those of birds and mammals, despite their key evolutionary position linking amphibians, reptiles, birds and mammals. Here, employing an Alligator sinensis genomic bacterial artificial chromosome (BAC) library and available genome data, we characterized the genomic organization, evolution and expression of TRB and TRG loci in Alligator sinensis . According to the sequencing data, the Alligator sinensis TRB locus spans approximately 500 Kb of genomic DNA containing two D-J-C clusters and 43 V gene segments and is organized as Vβ (39) -pJβ1-pCβ1-pDβ1-Dβ2- Jβ2 (12) -Cβ2-Vβ (4) , whereas the TRG locus spans 115 Kb of DNA genomic sequence consisting of 18 V gene segments, nine J gene segments and one C gene segment and is organized in a classical translocon pattern as Vγ (18) –Jγ (9) -Cγ. Moreover, syntenic analysis of TRB and TRG chain loci suggested a high degree of conserved synteny in the genomic regions across mammals, birds and Alligator sinensis. By analysing the cloned TRB / TRG cDNA, we identified the usage pattern of V families in the expressed TRB and TRG . An analysis of the junctions of the recombined VJ revealed the presence of N and P nucleotides in both expressed TRB and TRG sequences. Phylogenetic analysis revealed that TRB and TRG loci possess distinct evolutionary patterns. Most Alligator sinensis V subgroups have closely related orthologues in chicken and duck, and a small number of Alligator sinensis V subgroups have orthologues in mammals, which supports the hypothesis that crocodiles are the closest relatives of birds and mammals. Collectively, these data provide insights into TCR gene evolution in vertebrates and improve our understanding of the Alligator sinensis immune system.
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age and gender related accumulation of perfluoroalkyl substances in captive Chinese Alligators Alligator sinensis
Environmental Pollution, 2013Co-Authors: Jianshe Wang, Fang Zhang, Renping Wang, Yating Zhang, Leo W Y Yeung, Sachi Taniyasu, Eriko Yamazaki, Nobuyoshi YamashitaAbstract:Fourteen perfluoroalkyl substances (PFASs) were measured in serum of the highly endangered captive Chinese Alligators, whole body homogenates of six kinds of fish (Alligator prey species), and pond water (Alligator habitat) in the Anhui Research Center for Chinese Alligator Reproduction. Six PFASs, including PFOS and five perfluorinated carboxylates, were detected in all Alligator samples. The most dominant PFAS was PFUnDA, with a mean value of 31.4 ng/mL. Significant positive correlations were observed among the six PFASs, suggesting that they shared similar sources of contamination. Significantly higher PFOS and PFUnDA levels were observed in males, but the other four PFCAs did not differ between genders. An age related PFAS bioaccumulation analysis showed a significant negative correlation of the concentrations for five PFCAs to age, which means that higher concentrations were found in younger animals. Bioaccumulation factors (BAF) in fish for PFASs ranged from 21 to 28,000, with lower BAF for PFOA than that for longer carbon chain PFCAs, including PFUnDA, PFDA, and PFNA.
Ruidong Zhang - One of the best experts on this subject based on the ideXlab platform.
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cloning characterisation and expression profile of kisspeptin1 and the kisspeptin1 receptor in the hypothalamic pituitary ovarian axis of Chinese Alligator Alligator sinensis during the reproductive cycle
Reproduction Fertility and Development, 2020Co-Authors: Yongkang Zhou, Ruidong Zhang, Ali Izaz, Renping Wang, Shulong Duan, Xiaobing WuAbstract:Kisspeptin1 (Kiss1), a product of the Kiss1 gene, plays an important role in the regulation of reproduction in vertebrates by activating the Kiss1 receptor (Kiss1R) and its coexpression with gonadotrophin-releasing hormone (GnRH) in GnRH neurons. The purpose of this study was to clone the Kiss1 and Kiss1R genes found in the brain of Alligator sinensis and to explore their relationship with reproduction. The full-length cDNA of Kiss1 is 816bp, the open reading frame (ORF) is 417bp and the gene encodes a 138-amino acid precursor protein. The full-length cDNA of Kiss1R is 2348bp, the ORF is 1086bp and the gene encodes a 361-amino acid protein. Quantitative polymerase chain reaction showed that, except for Kiss1R expression in the hypothalamus, the expression of Kiss1 and Kiss1Rduring the reproductive period of A. sinensis was higher than that in the hypothalamus, pituitary gland and ovary during the hibernation period. The changes in GnRH2 mRNA in the hypothalamus were similar to those of GnRH1 and peaked during the reproductive period. This study confirms the existence of Kiss1 and Kiss1R in A. sinensis and the findings strongly suggest that Kiss1 and Kiss1R may participate in the regulation of GnRH secretion in the hypothalamus of Alligators during the reproductive period. Furthermore, this is the first report of the full-length cDNA sequences of Kiss1 and Kiss1R in reptiles.
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molecular cloning of androgen receptor and gene expression of sex steroid hormone receptors in the brain of newborn Chinese Alligator Alligator sinensis
Gene, 2018Co-Authors: Yongkang Zhou, Ruidong Zhang, Ying Zhang, Mengjuan Wu, Ali Izaz, Renping Wang, Xiaobing WuAbstract:Abstract Sex steroid hormones play an important role in mediating physiological responses and developmental processes through their receptors across all vertebrates. Chinese Alligator (Alligator sinensis) is a critically endangered reptile species unique to China. In this study, we have cloned one of the sex steroid hormone receptor genes, androgen receptor (AR) from the brain of Chinese Alligator for the first time. The full-length AR cDNA is 2717 bp in length with an open reading frame (ORF) encoding 722 amino acids. Amino acid alignment analyses indicated that the ARs exhibit highly conserved functional domains. Especially, the P-box and D-box, which are essential to ensure that receptor binding to the androgen response elements, are completely conserved in selected species. Using the quantitative real-time PCR (qPCR), the spatial expression of four receptor mRNAs in all newborn brain tissues and temporal expression of them in the cerebrum during the embryonic development in Chinese Alligators were investigated. The results of qPCR showed ubiquitous expression of the four receptor mRNAs in all newborn brain tissues examined and significant changes in the expression levels of these receptor mRNAs in the embryonic development. These results suggest that sex steroid hormones might play an important role in the regulation of complex neuroendocrine activities in newborn Chinese Alligator. Furthermore, these data provide an important foundation for further studies on endocrinology and molecular biology of non-mammalian sex steroid hormone receptors.
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molecular cloning of esr2 and gene expression analysis of esr1 and esr2 in the pituitary gland of the Chinese Alligator Alligator sinensis during female reproductive cycle
Gene, 2017Co-Authors: Ruidong Zhang, Rong Wu, Yongkang Zhou, Xiaobing WuAbstract:Abstract Estrogens play critical roles in reproductive physiology via estrogen receptors (ESRs) in vertebrates, including reptiles. Chinese Alligator (Alligator sinensis) is an endemic and endangered reptile species in China. In the present study, we cloned ESR2 gene from the ovary using rapid amplification of cDNA ends (RACE), investigated the spatial expression of ESRs in various tissues and temporal expression of ESRs in the pituitary glands during the reproductive cycle in Chinese Alligators by quantitative real-time PCR (qPCR). Bioinformatics and phylogenetic analysis of deduced ESR2 protein were also performed. The full-length cDNA of the ESR2 is 1647 bp in length, with an open-reading frame encoding 548 amino acids. The bioinformatics analysis indicated that the deduced amino acid sequence of Alligator ESR2 was highly conserved with that of other vertebrate species. In addition, compared to human ESR2, the 14 amino acids in the Alligator ESR2 that are essential for specific recognition of estradiol are entirely conserved. The phylogenetic analysis showed that Alligators were more closely related to birds than to other reptiles. The results of qPCR showed that the tissue distribution patterns of both ESR subtype mRNAs appeared to be different. In male tissues, the highest mRNA level of both ESRs is in the liver. While in female tissues, ESR1 and ESR2 showed the highest mRNA level in the hypothalamus and pituitary gland, respectively. During the female reproductive cycle, the expression level of ESR1 mRNA increased from the initial post-hibernation period to the reproductive period, reached its peak in the reproductive period, and then decreased in the autumn active period and hibernation period. Conversely, the highest transcription level of ESR2 was observed in the hibernation period.
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immunohistochemical localization of somatostatin in the brain of Chinese Alligator Alligator sinensis
Anatomical Record-advances in Integrative Anatomy and Evolutionary Biology, 2017Co-Authors: Huan Wang, Shengzhou Zhang, Yongkang Zhou, Ruidong Zhang, Xiaobing WuAbstract:In this study, the regional distribution and histological localization of somatostatin (SS) immunoreactive (IR) perikarya and fibers was investigated for the first time in the brain of adult Chinese Alligator by immunohistochemical method. The results showed SS-IR perikarya and fibers were widely distributed in various parts of the brain except for olfactory bulbs. In the telencephalon, SS-IR perikarya were predominantly located in the cellular layer and deep plexiform layer of dorsomedial and medial cortex, less in the dorsal and lateral cortex, while SS-IR fibers were found in all layers of the cerebral cortex. SS-IR perikarya and fibers were also detected in the dorsal ventricular ridge, hippocampus cortex, accessory olfactory bulb nuclearus, lenticular nucleus and caudate nucleus. In the diencephalon, SS-IR perikarya and fibers were mainly present in supraoptic nucleus, paraventricular nucleus of hypothalamus, recessus infundibular nucleus, median eminence, the pineal gland and pituitary gland, in which the IR-fibers were abundant, appearing dot-shaped and varicosity-like. In the mesencephalon, they were present in tectum cortex, ependyma of cerebral aqueduct and the periaqueductal grey matter. Additionally, they were also detected in Purkinje's cellular layer of cerebellum, in the reticularis nucleus and raphe nucleus of medulla oblongata. The distribution pattern of SS-IR perikarya and fibers in the brain of Chinese Alligator is generally similar to that reported in other reptiles, but also has some specific features. The wide distribution indicated that SS might be a neurotransmitter or neuromodulator which acts on many kinds of target cells with a wide range of physiological functions. This article is protected by copyright. All rights reserved.
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molecular cloning characterization tissue distribution and mrna expression changes during the hibernation and reproductive periods of estrogen receptor alpha esr1 in Chinese Alligator Alligator sinensis
Comparative Biochemistry and Physiology B, 2016Co-Authors: Ruidong Zhang, Yongkang Zhou, Huan Wang, Rong Wu, Yuehong Hu, Xiaobing WuAbstract:Abstract Chinese Alligator, Alligator sinensis , is a critically endangered reptile species unique to China. Little is known about the mechanism of growth- and reproduction-related hormones gene expression in Chinese Alligator. Estrogens play important roles in regulating multiple reproduction- and non-reproduction-related functions by binding to their corresponding receptors. Here, the full-length cDNA of estrogen receptor alpha ( ERα / ESR1 ) was cloned and sequenced from Chinese Alligator for the first time, which comprises 1764 bp nucleotides and encodes a predicted protein of 587 amino acids. Phylogenetic analysis of ESR1 showed that crocodilians and turtles were the sister-group of birds. The results of real-time quantitative PCR indicated that the ESR1 mRNA was widely expressed in the brain and peripheral tissues. In the brain and pituitary gland, ESR1 was most highly transcribed in the cerebellum. But in other peripheral tissues, ESR1 mRNA expression level was the highest in the ovary. Compared with hibernation period, ESR1 mRNA expression levels were increased significantly in the reproductive period ( P P > 0.05). The ESR1 mRNA expression levels changes during the two periods of different tissues suggested that ESR1 might play an important role in mediation of estrogenic multiple reproductive effects in Chinese Alligator. Furthermore, it was the first time to quantify ESR1 mRNA level in the brain of crocodilians, and the distribution and expression of ESR1 mRNA in the midbrain, cerebellum and medulla oblongata was also reported for the first time in reptiles.