中国东北地区黑腹果蝇(Drosophila melanogaster)P因子分布和来源

真核生物的转座因子(transposable elements)特别是果蝇P因子在研究生物进化上有重要的意义。以我国东北地区13个地方及毗邻的北京、烟台和呼和浩特三个地方共130个黑腹果蝇(D.melanogaster)单雌系为材料,对P因子序列的ORF2-ORF3区段进行PCR扩增,统计不同地方黑腹果蝇群体的P因子在此区段的缺失频率,再从整个地区来分析P因子缺失的分布规律,以推导东北地区黑腹果蝇中P因子的传递和扩散途径。结果显示P因子缺失频率由边境地区向内地逐渐递减,群体相对隔离的地方也较低,推断我国东北地区黑腹果蝇中P因子由朝鲜和俄罗斯向中国边境入侵后,逐步向中国内地扩散。

THE DISTRIBUTION AND ORIGIN OF P ELEMENTS IN DROSOPHILA MELANOGASTER STRAINS FROM NORTHEAST CHINA

Eukaryotic transposable elements, especially P transposable elements of Drosophla , are very important to study the evolution of biology. We collected 130 single - female lines of D. melanogaster from 13 places in Northeast China and 3 places nearby which are Beijing(BC), Yantai (YT) ,Huhehaote(HHT) in 1999 and 2000. We amplified the fragments from ORF2 to ORF3 of P elements using PCR and calculated the defective frequencies and defective parameters of P elements from different places. Basing on the distribution of defective P elements, we suggested the invasion route of P elements of D. melanogaster in Northeast China. The results indicate that the defective frequencies decrease from the frontier to the inland, and in the isolated places the frequencies are lower. It is proposed that P elements of D. melanogaster in Northeast China originate from Korea and Russia to the frontiers of P.R. China, then expand into the inland.