MBE Advance Access published online on July 24, 2008
Molecular Biology and Evolution, doi:10.1093/molbev/msn162
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Research Article |
Recent origins of sperm genes in Drosophila
Department of Biology and Biochemistry, University of Bath, Bath BA2 7AY, U.K
* Corresponding author: Steve Dorus Email: S.Dorus{at}bath.ac.uk. Phone: +44-1225-383128.
Received for publication May 16, 2008. Revision received July 16, 2008. Accepted for publication July 18, 2008.
Newly created genes often acquire testis specific or enhanced expression but neither the mechanisms responsible for this specificity nor the functional consequences of these evolutionary processes are well understood. Genomic analyses of the D. melanogaster sperm proteome (DmSP) has identified two recently evolved gene families on the melanogaster lineage and four genes created by retrotransposition during the evolution of the melanogaster group which encode novel sperm components. The expanded Mst35B (protamine) and tektin gene families are the result of tandem duplication events with all family members displaying testis-specific expression. The Mst35B family encodes rapidly evolving protamines that display a robust signature of positive selection within the DNA-binding high-mobility group box consistent with functional diversification in genome repackaging during sperm nuclear remodeling. The Mst35B paralogs also reside in a significant regional cluster of testis-overexpressed genes. Tektins, known components of the axoneme, are encoded by three nearly identical X-linked genes, a finding consistent with very recent gene family expansion. In addition to localized duplication events, the evolution of the sperm proteome has also been driven by recent retrotransposition events resulting in Cdlc2, CG13340, Vha36 and CG4706. Cdlc2, CG13340, Vha36 all display high levels of overexpression in the testis and Cdlc2 and CG13340 reside within testis-overexpressed gene clusters. Thus, gene creation is a dynamic force in the evolution of sperm composition and possibly function, which further suggests that acquisition of molecular functionality in sperm may be an influential pathway in the fixation of new genes.
Key Words: sperm • gene duplication • retrotransposition • testis • protamines • proteomics
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  G. D. Findlay, M. J. MacCoss, and W. J. Swanson Proteomic discovery of previously unannotated, rapidly evolving seminal fluid genes in Drosophila Genome Res., May 1, 2009; 19(5): 886 - 896. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. S. Kelleher and T. A. Markow Duplication, Selection and Gene Conversion in a Drosophila mojavensis Female Reproductive Protein Family Genetics, April 1, 2009; 181(4): 1451 - 1465. [Abstract] [Full Text] [PDF]
|
|