Masu salmon,Oncorhynchus masou masou,is one of the most valuable fishery species that has been introduced to China,though to date no studies on the genetic diversity and genetic relationship among hatchery populations...Masu salmon,Oncorhynchus masou masou,is one of the most valuable fishery species that has been introduced to China,though to date no studies on the genetic diversity and genetic relationship among hatchery populations has been performed with molecular markers.We undertook such a study and sampled 120 individuals from three hatchery stocks and analyzed 20 microsatellite loci.All loci were polymorphic and a total of 91 alleles were detected.A relatively low level of genetic diversity was revealed with effective number of allele of 3.1094,3.3299 and 3.1894 and expected heterozygosity of 0.6600,0.6648 and 0.6638 in the three stocks,respectively.Deviations from Hardy-Weinberg equilibrium were found due to heterozygote deficit.Accordingly,evidence of genetic bottlenecks were found in the three stocks.An individual assignment test demonstrated that 85% of individuals were correctly assigned into their original stocks.Pairwise Fst revealed that significant differentiation occurred between these three stocks.The results of the study indicated that disequilibrium of genetic structure and differentiation has occurred in all three stocks.This information collectively provides a basis for measures to avoid of loss of genetic diversity and introgression in Chinese aquaculture.展开更多
The T gene, which was cloned from the mitochondria of tumorous stem mustard （Brassica juncea var. tumida）, is a cytoplas- mic male sterility （CMS）-related gene that can produce two transcripts, T1170 and T1243. Th...The T gene, which was cloned from the mitochondria of tumorous stem mustard （Brassica juncea var. tumida）, is a cytoplas- mic male sterility （CMS）-related gene that can produce two transcripts, T1170 and T1243. The latter is transcribed with the un- cleaved intron Tinll. In our previous study, transgenic Arabidopsis thaliana plants over-expressing the T1243 transcript （OE-T1243） showed a severe male-sterile phenotype, whereas OE-Tll70 plants did not. However, the functional mechanism of the T gene in B. Juncea remained unknown. In this study, microscopic analyses of paraffin sections of anthers confirmed that OE-T1243 plants did not produce normal pollen, whereas OE-T1170 plants did. We analyzed the transcription of 15 anther development-related genes and found that transcript levels of nozzle/sporocyteless and barely any meristem 1 and 2 were markedly lower in OE-T1243 plants than those in wild type, while the transcript levels of these genes in OE-Tll70 plants were unchanged. To investigate the potential roles of TinH, we inserted the TinH sequence upstream of a minimal region （-60） of the cauliflower mosaic virus 35S promoter fused to the 5＇ end of the 13-glucuronidase （GUS） reporter gene. Analysis of the transgenic plants suggested that TinH acted as an enhancer to significantly increase GUS expression. The potential action mechanism is that the TinH intron acts as an enhancer to affect the function of the CMS-related gene T.展开更多
基金HRFRI Basic Science Research Special Funds(2009HSYZX-YY-10)Heilongjiang Natural Science Fund (C201044)Heilongjiang Postdoctoral Sustentation Fund (LRB10-081)
文摘Masu salmon,Oncorhynchus masou masou,is one of the most valuable fishery species that has been introduced to China,though to date no studies on the genetic diversity and genetic relationship among hatchery populations has been performed with molecular markers.We undertook such a study and sampled 120 individuals from three hatchery stocks and analyzed 20 microsatellite loci.All loci were polymorphic and a total of 91 alleles were detected.A relatively low level of genetic diversity was revealed with effective number of allele of 3.1094,3.3299 and 3.1894 and expected heterozygosity of 0.6600,0.6648 and 0.6638 in the three stocks,respectively.Deviations from Hardy-Weinberg equilibrium were found due to heterozygote deficit.Accordingly,evidence of genetic bottlenecks were found in the three stocks.An individual assignment test demonstrated that 85% of individuals were correctly assigned into their original stocks.Pairwise Fst revealed that significant differentiation occurred between these three stocks.The results of the study indicated that disequilibrium of genetic structure and differentiation has occurred in all three stocks.This information collectively provides a basis for measures to avoid of loss of genetic diversity and introgression in Chinese aquaculture.
基金supported by the National Natural Science Foundation ofChina(31071809)to Pei YanXi
文摘The T gene, which was cloned from the mitochondria of tumorous stem mustard （Brassica juncea var. tumida）, is a cytoplas- mic male sterility （CMS）-related gene that can produce two transcripts, T1170 and T1243. The latter is transcribed with the un- cleaved intron Tinll. In our previous study, transgenic Arabidopsis thaliana plants over-expressing the T1243 transcript （OE-T1243） showed a severe male-sterile phenotype, whereas OE-Tll70 plants did not. However, the functional mechanism of the T gene in B. Juncea remained unknown. In this study, microscopic analyses of paraffin sections of anthers confirmed that OE-T1243 plants did not produce normal pollen, whereas OE-T1170 plants did. We analyzed the transcription of 15 anther development-related genes and found that transcript levels of nozzle/sporocyteless and barely any meristem 1 and 2 were markedly lower in OE-T1243 plants than those in wild type, while the transcript levels of these genes in OE-Tll70 plants were unchanged. To investigate the potential roles of TinH, we inserted the TinH sequence upstream of a minimal region （-60） of the cauliflower mosaic virus 35S promoter fused to the 5＇ end of the 13-glucuronidase （GUS） reporter gene. Analysis of the transgenic plants suggested that TinH acted as an enhancer to significantly increase GUS expression. The potential action mechanism is that the TinH intron acts as an enhancer to affect the function of the CMS-related gene T.
