孟加拉笛鲷与四带笛鲷的微卫星分析

Microsatellite analysis of Lutjanus bengalensis and L.kasmira

采用聚丙烯酰胺凝胶电泳技术,从西大西洋笛鲷(Lutjanus campechanus)和勒氏笛鲷(L.russel-lii)的微卫星引物中筛选出适用于孟加拉笛鲷(L.bengalensis)和四带笛鲷(L.kasmira)的微卫星引物,并应用于三亚和湛江群体的遗传结构分析.结果表明:25对引物中筛选出13对可以稳定扩增出特异片段的引物,其中12对可在孟加拉笛鲷基因组中扩增出重复性好的特异性条带;10对可在四带笛鲷中扩增出重复性好的特异性条带,并且全部呈现出种内多态;9对为两个种通用.孟加拉笛鲷的湛江群体(ZMJ)和三亚群体(SMJ)、四带笛鲷的湛江群体(ZSD)和三亚群体(SSD)的平均等位基因数分别为:3.888 9、4.111 1、4.333 3、4.222 2;平均观测杂合度分别为:0.583 3、0.638 9、0.594 4、0.638 9;平均多态信息含量分别为:0.472 0、0.469 2、0.547 4、0.525 7.将本实验所得结果与笛鲷鱼其他研究结果进行比较分析,可以看出目前湛江海域野生笛鲷的遗传多样性整体比较丰富,但部分野生笛鲷已表现出杂合子缺失的趋势,这势必会引起将来遗传多样性的降低,所以要尽早对野生群体进行摸底调查,并找出解决养殖群体污染野生群体这一问题的方法.

In recent years, wild populations of snapper may have been polluted by the cultured populations due to the extensive snapper culture. So Lutjanus bengalensis and L. kasmira which haven＇ t be cultured yet for now were used as a base value to evaluate the pollution level of wild populations. With methods of polymerase chain reaction and polyacrylamide gel electrophoresis, the population genetic structures of L. bengalensis of Sanya（ SMJ）, L. ben- galensis of Zhanjiang （ ZMJ）, L. kasmira of Sanya （ SSD）, and L. kasmira of Zhanjiang （ZSD） in 2 species of snap- pers in South China Sea were revealed based on the microsatellite primers screened from 25 pairs primers from L. campechanus and L. russellii. Twelve pairs of primers could be amplified successfully with genome DNA of L. benga- lensis, and 10 pairs with L. kasmira. And all primers showed polymorphic in population of L. kasmira. The ampli- fied products of genomie DNA indicated that the mean number of alleles of 4 populations were ： 3. 888 9 （ ZMJ）, 4. 111 1 （SMJ）, 4.333 3 （ZSD）, 4.222 2 （SSD） ;mean observed heterozygosity （Ho） were： 0.583 3 （ZMJ）, 0. 638 9 （ SMJ）, 0. 594 4 （ ZSD）, 0.638 9 （SSD） ; and the mean polymorphism information content （PIC） were ： 0.472 0 （ZMJ）, 0.469 2 （SMJ）, 0.547 4 （ZSD）, 0.525 7 （SSD）. When compared with the results from other experiments, it shows that the current genetic diversity of wild snappers in Zhanjiang sea was at high level. At the same time, it is found that the loss of heterozygosity（LOH） in some of wild snapper population have already occurred, which must bring about a decline in the future genetic di- versity. So, in order to protect the wild snapper populations from genetic pollution of cultured population, investiga- tion for wild snapper populations and for applicable solutions should be carried out as soon as possible.