帘蛤科4种养殖蛤群体遗传多样性和种间关系的fAFLP分析

利用荧光标记扩增片段长度多态性(fAFLP)技术对文蛤(Meretrix meretrix)、青蛤(Cyclina sinensis)、菲律宾蛤仔(Ruditapes philippinarum)和硬壳蛤(Mercenaria mercenaria)4种帘蛤科贝类的群体遗传多样性和种间关系进行了研究。选择EcoRⅠ/MseⅠ进行酶切,使用6个E 3/M 3引物组合进行扩增,共获得1 096个位点,多态位点比率95.1%,片段长度50~456 bp。其中,文蛤、青蛤、菲律宾蛤仔和硬壳蛤分别得到681,715,702和694个位点,相应的多态位点比率为76.8%,81.7%,83.0%和75.1%,得到17个种特异性位点,可作为4物种特征标记。分析了群体遗传相似系数和遗传多样性指数以及种间遗传相似系数。结果表明,硬壳蛤群体遗传相似系数最高(0.670 9),遗传多样性指数最低(0.236 0);菲律宾蛤仔群体遗传相似系数最低(0.592 5),遗传多样性指数最高(0.261 8);根据遗传相似系数采用UPGMA法构建了4物种32个体的聚类图,表明文蛤与菲律宾蛤仔遗传关系最近,青蛤与其他3物种遗传关系较远。

Fluorescent amplified fragment length polymorphism (fAFLP) analysis of population genetic diversity and species relationships of four species of cultured clams in family Veneridae (Mollusca: Bivalvia)

By using the gastrin antiserum and the immunohistochemical method of Streotavidin-Peroxid(S-P), the investigation on the distributions of G cells in the digestive tract of Bostrichthys sinensis, Sparus latus, Paralichthys olivaceus, Sigauns fuscesens and Boleophthalmus pectinirostris was made. The distributions of the G cells are as follows: In Bostrichthys sinensis, the G cells are mainly located in intestine, rarely in rectum; In Sparus latus, the G cells were only observed in intestine, none in any other parts of the digestive tract; In Paralichthys olivaceus, the G cells were observed numerously in stamachus pyloricus and intestine; In Sigauns fuscesens, the G cells were distributed in pyloric caecum and intestine; In Boleophthalmus pectinirostris, the G cells were observed in stomachus carsiacus, stamachus pyloricus and intestine,mainly located in stamachus pyloricus. The G cells were detected mainly in the stomach and intestine in 5 kinds of marine fish, the results show that the gastrin was correlated with function of digestion and absorption. The G cells were of polymorphism in 5 kinds of marine fish. It was suggested that the gastrin might exert the digestive physiology in different modes of endocrine.