초파리의 P 전이인자의 Strain Type 에 대한 Type Conversion 에 관한 연구 = Studies on Type Conversion of P Element Strain Type in Drosophila Melanogaster

다국어 초록 (Multilingual Abstract)

161 isofemale lines of Drosophila melanogaster derived from Gwacheon wild population were used to make dysgenic hybrids in the P-M system. P factor activity and cytotypes of each isofemale line were measured by percent gonadal dysgenic sterility among female progenies from crosses with Canton-S female (M type) or Harwich male (P type). Most of the lines were presented Q (62.11%) and M`(34.17%) types, and a few lines were showing the weak P (2.48%) and M (1.24%). Type conversions among the three types, P, Q and M` were examined during the 10 generations in the laboratory condition. Average P factor activity (cross A) of three lines of P strain was 51.99% at foundation generation, and decreased rapidly during the five generations as under the 10% level. In the cross B for the cytotype, average hybrid sterility of P strain was increased gradually through 10 generations from 0 to 8.91%. However, spontaneous changes of type conversions were not appeared in the both P factor activity and cytotypes of Q and M` strains. These observation seem to support the stochastic loss hypothesis of P element proposed by Engels (1981).