Transposition of P{lacW} gammaCop057302 into the germline of Drosophila melanogaster correlates with retaining of the original insertion

Abstract

We  performed  a  genetic  and  molecular  screening  in  Drosophila  melanogaster  in  order  to investigate the mobilization pattern of P{lacW} gammaCop057302 , a lethal transposon insertion located in 5’UTR of gammaCop gene from 100C chromosomal region. New mutant lines, with modified levels of eye  pigmentation,  were  obtained  consequent  to  transposition  in  both  male  and  female  germline.  A total  of  153 founder  individuals  were  preliminary  screened,  68  of them  descending  from  dysgenic males and 85 from dysgenic females. From a total of 114 reinsertion events occurring within the third chromosome, 98 were associated with an apparent conservation of the original insertion. A consistent tendency towards retaining of the original insertion has been also noticed in an older collection of 40 mutant lines harboring transposition events that also affect the third chromosome. 

Our  data  show  a  strong  correlation  between  transposition  and  the  retaining  of P{lacW} gammaCop057302  original insertion, a phenomenon that may unravel functional aspects of the Pelement's  mobilization  pattern.  Conservation  of  the  starting  element  may  also  represent  an  useful marker in genetic screenings aiming to detect local reinsertions of the P element.