A germline clone screen for fremale meiotic mutants in Drosophilia.
Drosophila is an excellent system in which to investigate the
molecular biology of meiosis. A large number of mutants that affect
meiosis have been discovered through genetic screens in Drosophila.
However, the designs of most previous screens did not allow the recovery
of mutations in essential genes. Here we describe a genetic screen that
can recover mutants in essential genes that are also required during
female meiosis. Thus far, we have conducted screens for meiotic mutants
on chromosome arms 2L and 3R. We utilize the FLP-FRT technology to
generate and select for homozygous mutant germline clones within
heterozygotes. The clones are assayed for autosomal meiotic
nondisjunction by crossing clone-bearing females to males that carry a
compound autosome (C(3)EN to screen 2L and C(2)EN to screen 3R). Progeny
from this cross can only arise from a homozygous mutant germline clone
in which nondisjunction occurred during meiosis. Since the rare progeny
will be heterozygous for the mutagenized chromosome arm, they are used
to isolate a stock of the putative meiotic mutant through a subsequent
series of crosses. Total 25,571 chromosome arms 3R and 20,817 chromosome
arms 2L have been screened. Twelve mutants have been recovered (10 for
3R and 2 for 2L). Three of these are homozygous lethal. We are currently
mapping these mutants and characterizing their phenotypes.
* Ong, S.K, S. Hawley and S. Page. University of Missouri--Kansas
City and Stowers Institute for Medical Research, Kansas City.