奥利亚罗非鱼微卫星位点的筛选

从GenBank上选取40对尼罗罗非鱼(Oreochromis niloticus)的微卫星引物,分别在奥利亚罗非鱼(Oreo-chromis aureus)(83系)、红色奥利亚罗非鱼、奥利亚罗非鱼(02系)和尼罗罗非鱼的基因组上进行扩增。40对引物中有37对(92.5%)可进行有效扩增,32对引物(80%)可检测到个体间等位基因的多态性。其中引物UNH168与奥利亚罗非鱼的性别相关,在雌性个体中可扩增出二条大小不同的特异带(分别为135和171 bp),在雄性个体中则只有一条(171 bp)。将特异条带回收、克隆并测序,结果显示雌雄个体中171 bp条带的序列完全相同,包括103bp的侧翼序列和34个CA重复,在雌性个体中获得的135 bp条带则只有16个CA重复。引物UNH846、UNH860和UNH995可鉴别奥利亚罗非鱼和尼罗罗非鱼,UNH890可鉴别出红色奥利亚罗非鱼。可见,大部分的尼罗罗非鱼微卫星位点存在于奥利亚罗非鱼中。

Selection of Microsatellite Loci of Oreochromis aureus

Forty pairs of microsatellite primers for Oreochromis niloticus from GenBank were tested on O.aureus,including Red O.aureus,O.aureus(02),O.aureus(83) as well as O.niloticus.The results showed that 37 pairs of primers(92.5%) were amplified successfully,of which 32 pairs(80%) displayed polymorphism.The primer UNH168 showed strong association with sex.The 135bp allele of UNH168 was found only in female fish while the 171bp allele was found in both sex.The sex-specific bands produced by primer UNH168 were amplified,and then cloned after gel extraction.The sequenced result showed that the 171bp allele had(ca)34 repeats and the sequences were exactly the same in both sexes.While the 135bp allele of female O.aureus included only(ca)16 repeats.In addition,3 pairs of primers(UNH846,UNH860,UNH995) could distinguish between O.niloticus and O.aureus.The amplified band of primer UNH890 was only found in red O.aureus.These results indicated that most of O.niloticus microsatellite loci assayed could be amplified successfully in O.aureus.