[Objective] To investigate the genetic diversity, molecular phylogeny and origination in Wanbei cattle. [Methedl Blood samples were collected from 50 Wanbei cattle and 14 local cattle breeds. According to the bovine M...[Objective] To investigate the genetic diversity, molecular phylogeny and origination in Wanbei cattle. [Methedl Blood samples were collected from 50 Wanbei cattle and 14 local cattle breeds. According to the bovine MHC gene sequence, one pair of primers was designed and used for PCR amplification. The sequences of amplified MHC genes were aligned to detect MHC haplotypes and nucleotide polyrnorphisms. A phy- Iogenetic tree based on the MHC gene was also constructed. [Result] A total of 24 polymorphic loci covering 7.86% of the entire length of the se- quences and seven MHC haplotypes were detected. Among these polymorphic loci, there were 18 transitions, 1 tranversions and 5 transition / tran- version. The difference in nucleotide sequence was 0.26% -4.53% between the haplotypes. The nucleotide diversity （π value） and haplotype di- versity （H） were 0.012 - 0.019 and 0.602 - 0.617, respectively. [ Conclusion ] Wanbei cattle do not have rich MHC genetic diversity. They have closer aenetic relationship with Luxi cattle, and both are within the same sister group.展开更多
supported by the Earmarked Fund for the Modern Agroindustry Technology Research System, China （CARS-41）;the National High Technology Research and Development Program of China （2011AA100301）
The worldwide declines in amphibian populations have largely been caused by infectious fungi and bacteria. Given that vertebrate immunity against these extracellular pathogens is primarily functioned by the major hist...The worldwide declines in amphibian populations have largely been caused by infectious fungi and bacteria. Given that vertebrate immunity against these extracellular pathogens is primarily functioned by the major histocompatibility complex（MHC） class Ⅱ molecules, the characterization and the evolution of amphibian MHC class Ⅱ genes have attracted increasing attention. The polymorphism of MHC class Ⅱ genes was found to be correlated with susceptibility to fungal pathogens in many amphibian species, suggesting the importance of studies on MHC class Ⅱ genes for amphibians. However, such studies on MHC class Ⅱ gene evolution have rarely been conducted on amphibians in China. In this study, we chose Omei treefrog（Rhacophorus omeimontis）, which lived moist environments easy for breeding bacteria, to study the polymorphism of its MHC class Ⅱ genes and the underlying evolutionary mechanisms. We amplified the entire MHC class ⅡB exon 2 sequence in the R. omeimontis using newly designed primers. We detected 102 putative alleles in 146 individuals. The number of alleles per individual ranged from one to seven, indicating that there are at least four loci containing MHC class ⅡB genes in R. omeimontis. The allelic polymorphism estimated from the 102 alleles in R. omeimontis was not high compared to that estimated in other anuran species. No significant gene recombination was detected in the 102 MHC class ⅡB exon 2 sequences. In contrast, both gene duplication and balancing selection greatly contributed to the variability in MHC class ⅡB exon 2 sequences of R. omeimontis. This study lays the groundwork for the future researches to comprehensively analyze the evolution of amphibian MHC genes and to assess the role of MHC gene polymorphisms in resistance against extracellular pathogens for amphibians in China.展开更多
基金supported by the Suzhou Key Technologies R&D Program ( 2009021)
文摘[Objective] To investigate the genetic diversity, molecular phylogeny and origination in Wanbei cattle. [Methedl Blood samples were collected from 50 Wanbei cattle and 14 local cattle breeds. According to the bovine MHC gene sequence, one pair of primers was designed and used for PCR amplification. The sequences of amplified MHC genes were aligned to detect MHC haplotypes and nucleotide polyrnorphisms. A phy- Iogenetic tree based on the MHC gene was also constructed. [Result] A total of 24 polymorphic loci covering 7.86% of the entire length of the se- quences and seven MHC haplotypes were detected. Among these polymorphic loci, there were 18 transitions, 1 tranversions and 5 transition / tran- version. The difference in nucleotide sequence was 0.26% -4.53% between the haplotypes. The nucleotide diversity （π value） and haplotype di- versity （H） were 0.012 - 0.019 and 0.602 - 0.617, respectively. [ Conclusion ] Wanbei cattle do not have rich MHC genetic diversity. They have closer aenetic relationship with Luxi cattle, and both are within the same sister group.
基金supported by the Earmarked Fund for the Modern Agroindustry Technology Research System, China (CARS-41)the National High Technology Research and Development Program of China (2011AA100301)
文摘supported by the Earmarked Fund for the Modern Agroindustry Technology Research System, China （CARS-41）;the National High Technology Research and Development Program of China （2011AA100301）
基金supported by the National Natural Science Foundation of China(No.31201713,No.31270425 and No.31470442)
文摘The worldwide declines in amphibian populations have largely been caused by infectious fungi and bacteria. Given that vertebrate immunity against these extracellular pathogens is primarily functioned by the major histocompatibility complex（MHC） class Ⅱ molecules, the characterization and the evolution of amphibian MHC class Ⅱ genes have attracted increasing attention. The polymorphism of MHC class Ⅱ genes was found to be correlated with susceptibility to fungal pathogens in many amphibian species, suggesting the importance of studies on MHC class Ⅱ genes for amphibians. However, such studies on MHC class Ⅱ gene evolution have rarely been conducted on amphibians in China. In this study, we chose Omei treefrog（Rhacophorus omeimontis）, which lived moist environments easy for breeding bacteria, to study the polymorphism of its MHC class Ⅱ genes and the underlying evolutionary mechanisms. We amplified the entire MHC class ⅡB exon 2 sequence in the R. omeimontis using newly designed primers. We detected 102 putative alleles in 146 individuals. The number of alleles per individual ranged from one to seven, indicating that there are at least four loci containing MHC class ⅡB genes in R. omeimontis. The allelic polymorphism estimated from the 102 alleles in R. omeimontis was not high compared to that estimated in other anuran species. No significant gene recombination was detected in the 102 MHC class ⅡB exon 2 sequences. In contrast, both gene duplication and balancing selection greatly contributed to the variability in MHC class ⅡB exon 2 sequences of R. omeimontis. This study lays the groundwork for the future researches to comprehensively analyze the evolution of amphibian MHC genes and to assess the role of MHC gene polymorphisms in resistance against extracellular pathogens for amphibians in China.
