郑州黑腹果蝇自然群体P-M细胞型多态性研究

A Study on P M Cytotype Polymorphism in a Natural Population of Drosophila Melanogaster in China

应用性腺败育频率的遗传分析方法，对郑州黑腹果蝇自然群体的Ｐ因子活性和细胞型进行了较详尽的剖析。结果发现，该群体的Ｐ因子活性是单态的；而细胞型在群体、单雌系内和个体间皆表现出多态现象；该群体为缺乏完整Ｐ因子的Ｍ′品系。提出了Ｑ因子调控模型，以解释在缺乏完整Ｐ因子的Ｍ′品系中细胞型决定和多态现象产生的机理，并对细胞型的频率分布规律与平均ＧＤ（性腺）不育频率之间的内在联系进行了讨论。

In Drosophila melanogaster the P M hybrid dysgenesis results from the interaction of two genetic components:P elements and M cytotype. Both the components of a wild population of D. melanogaster from Zhengzhou, were examined and studied in detail by genetic analysis of the GD sterility. The result shows that the population is M′ strain with defective P elements. No P elements active for potential GD sterility were revealed in all the tested males, presenting monomorphism for the P element activity. But the females among and within the isofemale lines as well as in the population tested individually exhibited various abilities to repress GD sterility (0～100%), presenting clearly P M cytotype polymorphism. Here we propose a model of Q element regulation for the cytotype determing and the polymorphism forming mechanism in the M′ natural populations and isofemale lines without any intact P elements. The internal relations between distributior of P M cytotypes and the mean GD frequencies among and within the isofemale lines are discussed.