Evolution in the fast lane: rapidly evolving sex-related genes in Drosophila.
A large portion of the annotated genes in Drosophila melanogaster show sex-biased expression, indicating that sex and reproduction-related genes (SRR genes) represent an appreciable component of the genome. Previous studies, in which subsets of genes were compared among few Drosophila species, have found that SRR genes exhibit unusual evolutionary patterns. Here, we have used the newly released genome sequences from 12 Drosophila species, coupled to a larger set of SRR genes, to comprehensively test the generality of these patterns. Among 2505 SRR genes examined, including ESTs with biased expression in reproductive tissues and genes characterized as involved in gametogenesis, we find that a relatively high proportion of SRR genes have experienced accelerated divergence throughout the genus Drosophila. Several testis-specific genes, male seminal fluid proteins (SFPs), and spermatogenesis genes show lineage-specific bursts of accelerated evolution and positive selection. SFP genes also show evidence of lineage-specific gene loss and/or gain. These results bring us closer to understanding the details of the evolutionary dynamics of SRR genes with respect to species divergence.
Department of Biology, McMaster University, Hamilton, Ontario L8S 4K1, Canada. singh@mcmaster.ca
Wilfried
W
Haerty
Santosh
S
Jagadeeshan
Rob J
RJ
Kulathinal
Alex
A
Wong
Kristipati
K
Ravi Ram
Laura K
LK
Sirot
Lisa
L
Levesque
Carlo G
CG
Artieri
Mariana F
MF
Wolfner
Alberto
A
Civetta
Rama S
RS
Singh
D000818:Animals; D005075:Biological Evolution; D004330:Drosophila / Q000145:classification / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D029721:Drosophila Proteins / Q000235:genetics; D005260:Female; D017344:Genes, Insect; D008297:Male; D008957:Models, Genetic; D009866:Oogenesis / Q000235:genetics; D010053:Ovary / Q000378:metabolism; D010802:Phylogeny; D012098:Reproduction / Q000235:genetics; D012641:Selection, Genetic; D012727:Sex Characteristics; D019849:Sex Determination Processes; D013091:Spermatogenesis / Q000235:genetics; D013737:Testis / Q000378:metabolism
D029721:Drosophila Proteins