Zeocin can cause double strand breaks of DNA and thus may be employed as a mutagen. In this study, two strains of Nannochloropsis oceanica, the wild and the Zeocin-tolerant strains, were re-sequenced to verify such fu...Zeocin can cause double strand breaks of DNA and thus may be employed as a mutagen. In this study, two strains of Nannochloropsis oceanica, the wild and the Zeocin-tolerant strains, were re-sequenced to verify such function of Zeocin, The results showed that Zeocin can mutate the N. oceanica genome and cause the structural variation. Zeocin either swept away or selected the alleles of genes functioning in ubiquitin-mediated proteolysis, alpha-linolenic acid metabolism, ascorbate and aldarate metabolism, ribosome biogenesis, and circadian rhythm, indicating that N. oceanica may have adjusted its metabolic performances for protein, carbohydrate, and lipid, and changed its ribosome biosynthesis and living rhythm to survive in Zeocin containing medium. In addition, Zeocin caused mutation may have influenced the expression of a set of tanscription factors. It was concluded that Zeocin effectively caused the structural variation of the genome of N. oceanica, and forced the microalgae to select out the alleles of a set of genes around these variations in order to adapt to Zeocin containing medium. Further studies on the genetic basis of the phenotypic adaptation of this haploid and asexual microalga and the application of Zeocin to its genetic improvement are very important.展开更多
Half-smooth tongue sole (Cynoglossus semilaevis) is a promising species for aquaculture in China.The wild population of C. semilaevis is under threat from environmental factors. Microsatellite markers are very suitabl...Half-smooth tongue sole (Cynoglossus semilaevis) is a promising species for aquaculture in China.The wild population of C. semilaevis is under threat from environmental factors. Microsatellite markers are very suitable for assessing genetic diversity. Four microsatellite-enriched libraries of half smooth tongue sole (Cynoglossus semilaevis) were constructed,from which 57 polymorphic microsatellites were isolated and characterized.The polymorphism of these microsatellites was assessed by genotyping in 30 individual fish.The number of alleles ranged from 2 to 11, with an average of 4.614 alleles per locus.The values of observed and expected heterozygosities ranged from 0.1000 to 1.0000 and from 0.0966 to 0.8847 respectively. Polymorphism information content (PIC) ranged from 0.0905 to 0.862.These markers would be useful for population structure assessment,genetic linkage map construction and parentage analysis for this species.展开更多
When selection increases the frequency of a beneficial gene substitution it can also increase the frequencies of linked neutral alleles through a process called genetic hitchhiking. A model built to investigate reduce...When selection increases the frequency of a beneficial gene substitution it can also increase the frequencies of linked neutral alleles through a process called genetic hitchhiking. A model built to investigate reduced genetic diversity in Pleistocene hominins shows that genetic hitchhiking can have a strong effect on neutral diversity in the presence of culturally mediated mi- gration. Under conditions in which genetic and cultural variants are transmitted symmetrically, neutral genes may also hitchhike to higher frequencies on the coattails of adaptive cultural traits through a process called cultural hitchhiking. Cultural hitchhiking has been proposed to explain why some species of matrilineal whales display relatively low levels of mitochondrial DNA diver- sity, and it may be applicable to humans as well. This paper provides a critical review of recent models of both types of hitch- hiking in socially structured populations. The models＇ assumptions and predictions are compared and discussed in the hope that studies of reduced genetic diversity in humans might improve our understanding of reduced genetic diversity in other species, and vice versa展开更多
基金funded by the National Natural Science Foundation of China(No.31270408)the National High Technology Research and Development Program(863 Program) of China(No.2014AA022001)
文摘Zeocin can cause double strand breaks of DNA and thus may be employed as a mutagen. In this study, two strains of Nannochloropsis oceanica, the wild and the Zeocin-tolerant strains, were re-sequenced to verify such function of Zeocin, The results showed that Zeocin can mutate the N. oceanica genome and cause the structural variation. Zeocin either swept away or selected the alleles of genes functioning in ubiquitin-mediated proteolysis, alpha-linolenic acid metabolism, ascorbate and aldarate metabolism, ribosome biogenesis, and circadian rhythm, indicating that N. oceanica may have adjusted its metabolic performances for protein, carbohydrate, and lipid, and changed its ribosome biosynthesis and living rhythm to survive in Zeocin containing medium. In addition, Zeocin caused mutation may have influenced the expression of a set of tanscription factors. It was concluded that Zeocin effectively caused the structural variation of the genome of N. oceanica, and forced the microalgae to select out the alleles of a set of genes around these variations in order to adapt to Zeocin containing medium. Further studies on the genetic basis of the phenotypic adaptation of this haploid and asexual microalga and the application of Zeocin to its genetic improvement are very important.
基金supported by the 863 Project of China(2006AA10A403)the Natural Science Foundation of China(No.30972244)Taishan Scholar Project of Shandong Province,China
文摘Half-smooth tongue sole (Cynoglossus semilaevis) is a promising species for aquaculture in China.The wild population of C. semilaevis is under threat from environmental factors. Microsatellite markers are very suitable for assessing genetic diversity. Four microsatellite-enriched libraries of half smooth tongue sole (Cynoglossus semilaevis) were constructed,from which 57 polymorphic microsatellites were isolated and characterized.The polymorphism of these microsatellites was assessed by genotyping in 30 individual fish.The number of alleles ranged from 2 to 11, with an average of 4.614 alleles per locus.The values of observed and expected heterozygosities ranged from 0.1000 to 1.0000 and from 0.0966 to 0.8847 respectively. Polymorphism information content (PIC) ranged from 0.0905 to 0.862.These markers would be useful for population structure assessment,genetic linkage map construction and parentage analysis for this species.
文摘When selection increases the frequency of a beneficial gene substitution it can also increase the frequencies of linked neutral alleles through a process called genetic hitchhiking. A model built to investigate reduced genetic diversity in Pleistocene hominins shows that genetic hitchhiking can have a strong effect on neutral diversity in the presence of culturally mediated mi- gration. Under conditions in which genetic and cultural variants are transmitted symmetrically, neutral genes may also hitchhike to higher frequencies on the coattails of adaptive cultural traits through a process called cultural hitchhiking. Cultural hitchhiking has been proposed to explain why some species of matrilineal whales display relatively low levels of mitochondrial DNA diver- sity, and it may be applicable to humans as well. This paper provides a critical review of recent models of both types of hitch- hiking in socially structured populations. The models＇ assumptions and predictions are compared and discussed in the hope that studies of reduced genetic diversity in humans might improve our understanding of reduced genetic diversity in other species, and vice versa
