Fa. Digilio et al., TOSCA - A DROSOPHILA GENE ENCODING A NUCLEASE SPECIFICALLY EXPRESSED IN THE FEMALE GERMLINE, Developmental biology, 178(1), 1996, pp. 90-100
We describe here a Drosophila gene, tosca (tos), that is specifically
expressed in the female germline. tos mRNA accumulates selectively wit
hin the pro-oocyte in germarial region 2 and persists throughout oogen
esis. In the early embryo, the maternally supplied tos mRNA is evenly
distributed at the syncytial blastoderm stage, but is excluded from th
e forming cells when cellularization begins. fos product is the first
Drosophila member of the RAD2 protein family, a group of related DNA r
epair nucleases conserved from yeast to humans, Within the family, Tos
is more closely related to ExoI, a Schizosaccharomyces pombe 5' --> 3
' double-stranded DNA exonuclease specifically induced in meiotic prop
hase I. The definite oocyte localization of fos transcript during meio
sis and its ubiquitous distribution in early embryos suggest that ros
may play a role in mismatch repair during genetic recombination and ea
rly cleavage divisions. (C) 1996 Academic Press, Inc.