Genetic diversity and differentiation of the oyster Crassostrea plicatula populations from China’s coast were studied based on seven microsatellite loci. All loci showed high polymorphism for all five C. plicatula po...Genetic diversity and differentiation of the oyster Crassostrea plicatula populations from China’s coast were studied based on seven microsatellite loci. All loci showed high polymorphism for all five C. plicatula populations,with an average number of allele per locus of 19.3-27.9 and an average expected heterozygosity of 0.889-0.952. Significant departures from Hardy-Weinberg equilib-rium and deficits of heterozygotes were observed over most populations at each locus,which were fully explained by null alleles. Microsatellite analysis revealed significant subdivision in the C. plicatula populations. According to the neighbor-joining tree con-structed on the basis of the DA distance,the five populations fell into three regional groups,showing a relatively homogeneous genetic structure in geographically close populations. Assignation tests correctly assigned high percentages of individuals to their original populations and groups,and also confirmed the existence of genetic differentiation among C. plicatula populations. The results ob-tained in this study will facilitate the formulation of appropriate fisheries management programs,stock identification and conservation of biodiversity for the species.展开更多
Noroviruses (NoVs) are widespread causes of nonbacterial gastroenteritis. Outbreaks of NoVs caused diseases are commonly ascribed to the consumption of contaminated shellfish. The concentration and RNA extraction of N...Noroviruses (NoVs) are widespread causes of nonbacterial gastroenteritis. Outbreaks of NoVs caused diseases are commonly ascribed to the consumption of contaminated shellfish. The concentration and RNA extraction of NoVs are crucial steps of detecting NoVs in shellfish. This study aimed to select a simple, rapid and highly efficient recovery method of NoVs detection with real-time RT-PCR. Four methods of recovering GI.3 and GII.4 NoVs from spiked digestive tissues of oysters and clams, respectively, were compared, of them, the method involving proteinase K and PEG 8000 was found the most efficient. With this method, 9.3% and 13.1% of GI.3 and GII.4 NoVs were recovered from oysters and 9.6% and 12.3% of GI.3 and GII.4 NoVs were recovered from clams, respectively. This method was further used to detect NoVs in 84 oysters (Crassostrea gigas) and 86 clams (Ruditapes philippinarum) collected from 10 coastal cities in China from Jan. 2011 to Feb. 2012. The NoVs isolation rates were 10.47% of clams (9/86) and 7.14% of oysters (6/84). All the detected NoVs belonged to genotype GII. The NoVs recovery method selected is efficient for NoVs detection in oysters and clams.展开更多
基金grants from National High Technology Research and Development Program (2006AA10A409)National Natural Science Foundation of China (No 30571442)
文摘Genetic diversity and differentiation of the oyster Crassostrea plicatula populations from China’s coast were studied based on seven microsatellite loci. All loci showed high polymorphism for all five C. plicatula populations,with an average number of allele per locus of 19.3-27.9 and an average expected heterozygosity of 0.889-0.952. Significant departures from Hardy-Weinberg equilib-rium and deficits of heterozygotes were observed over most populations at each locus,which were fully explained by null alleles. Microsatellite analysis revealed significant subdivision in the C. plicatula populations. According to the neighbor-joining tree con-structed on the basis of the DA distance,the five populations fell into three regional groups,showing a relatively homogeneous genetic structure in geographically close populations. Assignation tests correctly assigned high percentages of individuals to their original populations and groups,and also confirmed the existence of genetic differentiation among C. plicatula populations. The results ob-tained in this study will facilitate the formulation of appropriate fisheries management programs,stock identification and conservation of biodiversity for the species.
基金supported by the China-Australia Bilateral Research Program (No. 2010DFA31720)the National Key Technology R&D Program (2012BAD28B05)
文摘Noroviruses (NoVs) are widespread causes of nonbacterial gastroenteritis. Outbreaks of NoVs caused diseases are commonly ascribed to the consumption of contaminated shellfish. The concentration and RNA extraction of NoVs are crucial steps of detecting NoVs in shellfish. This study aimed to select a simple, rapid and highly efficient recovery method of NoVs detection with real-time RT-PCR. Four methods of recovering GI.3 and GII.4 NoVs from spiked digestive tissues of oysters and clams, respectively, were compared, of them, the method involving proteinase K and PEG 8000 was found the most efficient. With this method, 9.3% and 13.1% of GI.3 and GII.4 NoVs were recovered from oysters and 9.6% and 12.3% of GI.3 and GII.4 NoVs were recovered from clams, respectively. This method was further used to detect NoVs in 84 oysters (Crassostrea gigas) and 86 clams (Ruditapes philippinarum) collected from 10 coastal cities in China from Jan. 2011 to Feb. 2012. The NoVs isolation rates were 10.47% of clams (9/86) and 7.14% of oysters (6/84). All the detected NoVs belonged to genotype GII. The NoVs recovery method selected is efficient for NoVs detection in oysters and clams.
