PgmNr D1178: Functional characterization of a gene family essential for Drosophila spermatogenesis.

Authors:
Benjamin Nicholson; Maxwell Kearns; Geoffrey Findlay


Institutes
College of the Holy Cross, Worcester, MA.


Keyword: spermatogenesis

Abstract:

Several of the most abundant proteins found in the proteome of mature sperm in Drosophila melanogaster are encoded by a single gene family.  To examine the functional consequences of the gene duplication events that gave rise to this family and to test whether these genes act redundantly, we used RNA interference to knock down expression of each gene in male testes. For most of the genes, knockdown males exhibited complete or near complete infertility. To investigate the nature of these fertility defects, we produced knockdown males that made sperm labeled with green fluorescent protein (GFP). These males transfer no (or very few) sperm to females during mating, and testis dissections revealed that knockdown males were unable to produce mature sperm. These results suggest that this family of proteins, in addition to being a major component of mature sperm, is also essential for spermatogenesis.  Current experiments are focused on determining the stage(s) of spermatogenesis at which each member of this gene family acts, which may allow us to determine the pattern(s) of neofunctionalization or subfunctionalization that occurred after the gene duplication events.