TY - JOUR T1 - Rapid evolution of female-biased genes among four species of <em>Anopheles</em> malaria mosquitoes JF - bioRxiv DO - 10.1101/081620 SP - 081620 AU - Francesco Papa AU - Nikolai Windbichler AU - Robert M. Waterhouse AU - Alessia Cagnetti AU - Rocco D’Amato AU - Tania Presampieri AU - Mara K. N. Lawniczak AU - Tony Nolan AU - Philippos Aris Papathanos Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/10/17/081620.abstract N2 - Understanding how phenotypic differences between males and females arise from the sex-biased expression of nearly identical genomes can often reveal important insights into the biology and evolution of a species. Among Anopheles mosquito species, these phenotypic differences include vectorial capacity, as it is only females that blood feed and thus transmit human malaria. Here, we use RNA-seq data from multiple tissues of four vectors spanning the Anopheles phylogeny to explore the genomic and evolutionary properties of sex-biased genes. We find that in these mosquitoes, in contrast to what has been found in many other organisms, female-biased genes are more rapidly evolving in sequence, expression, and genic turnover, than male-biased genes. Our results suggests that this atypical pattern may be due to the combination of sex-specific life history challenges encountered by females, such as blood feeding. Furthermore, female propensity to only mate once in nature in male swarms likely diminishes sexual selection of post-reproductive traits related to sperm competition among males. We also develop a comparative framework to systematically explore tissue- and sex-specific splicing, to document its conservation throughout the genus and identify a set of candidate genes for future functional analyses of sex-specific isoform usage. Finally, our data reveals that the deficit of male-biased genes on the X chromosomes in Anopheles is a conserved feature in this genus and can be directly attributed to chromosome-wide transcriptional regulation that demasculinizes the X in male reproductive tissues. ER -