Aguadé M
Departament de Genètica, Facultat de Biologia, Universitat de Barcelona, 08071 Barcelona, Spain.
Genetics. 1999 Jun;152(2):543-51. doi: 10.1093/genetics/152.2.543.
Nucleotide sequence variation at the Acp29AB gene region has been surveyed in Drosophila melanogaster from Spain (12 lines), Ivory Coast (14 lines), and Malawi (13 lines) and in one line of D. simulans. The approximately 1.7-kb region studied encompasses the Acp29AB gene that codes for a male accessory gland protein and its flanking regions. Seventy-seven nucleotide and 8 length polymorphisms were detected. Nonsynonymous polymorphism was an order of magnitude lower than synonymous polymorphism, but still high relative to other non-sex-related genes. In D. melanogaster variation at this region revealed no major genetic differentiation between East and West African populations, while differentiation was highly significant between the European and the two African populations. Comparison of polymorphism and divergence at synonymous and nonsynonymous sites showed an excess of fixed nonsynonymous changes, which indicates that the evolution of the Acp29AB protein has been driven by directional selection at least after the split of the D. melanogaster and D. simulans lineages. The pattern of variation in extant populations of D. melanogaster favors a scenario where the fixation of advantageous replacement substitutions occurred in the early stages of speciation and balancing selection is maintaining variation in this species.
已对来自西班牙（12个品系）、象牙海岸（14个品系）和马拉维（13个品系）的黑腹果蝇以及一个拟果蝇品系的Acp29AB基因区域的核苷酸序列变异进行了调查。所研究的约1.7kb区域包含编码雄性附腺蛋白的Acp29AB基因及其侧翼区域。检测到77个核苷酸多态性和8个长度多态性。非同义多态性比同义多态性低一个数量级，但相对于其他非性别相关基因仍然较高。在黑腹果蝇中，该区域的变异显示东非和西非种群之间没有主要的遗传分化，而欧洲种群与两个非洲种群之间的分化非常显著。同义位点和非同义位点的多态性与分化比较显示固定的非同义变化过多，这表明至少在黑腹果蝇和拟果蝇谱系分裂后，Acp29AB蛋白的进化受到定向选择的驱动。黑腹果蝇现存种群的变异模式支持这样一种情况，即有利替代替换的固定发生在物种形成的早期阶段，平衡选择维持了该物种的变异。
