Demasculinization of the Anopheles gambiae X chromosome

BMC Evolutionary Biology

Research Article

Andrea Crisanti¹  Nikolai Windbichler¹  Kalle Magnusson¹  Antonio M Mendes¹  Philippos-Aris Papathanos²  Gareth J Lycett³  Amy Lynd³ 

[1] Department of Life Sciences, Imperial College London, Imperial College Road, SW7 2AZ, London, UK;Department of Life Sciences, Imperial College London, Imperial College Road, SW7 2AZ, London, UK;Division of Biology, California Institute of Technology, Pasadena, CA, USA;Liverpool School of Tropical Medicine, Pembroke Place, L3 5QA, London, UK;

关键词: Anopheles gambiae;    demasculinization;    germline x-chromosome inactivation;    sexual antagonism;    dosage compensation;   

DOI  :  10.1186/1471-2148-12-69

 received in 2011-12-13, accepted in 2012-05-18,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundIn a number of organisms sex-biased genes are non-randomly distributed between autosomes and the shared sex chromosome X (or Z). Studies on Anopheles gambiae have produced conflicting results regarding the underrepresentation of male-biased genes on the X chromosome and it is unclear to what extent sexual antagonism, dosage compensation or X-inactivation in the male germline, the evolutionary forces that have been suggested to affect the chromosomal distribution of sex-biased genes, are operational in Anopheles.ResultsWe performed a meta-analysis of sex-biased gene expression in Anopheles gambiae which provides evidence for a general underrepresentation of male-biased genes on the X-chromosome that increased in significance with the observed degree of sex-bias. A phylogenomic comparison between Drosophila melanogaster, Aedes aegypti and Culex quinquefasciatus also indicates that the Anopheles X chromosome strongly disfavours the evolutionary conservation of male-biased expression and that novel male-biased genes are more likely to arise on autosomes. Finally, we demonstrate experimentally that transgenes situated on the Anopheles gambiae X chromosome are transcriptionally silenced in the male germline.ConclusionThe data presented here support the hypothesis that the observed demasculinization of the Anopheles X chromosome is driven by X-chromosome inactivation in the male germline and by sexual antagonism. The demasculinization appears to be the consequence of a loss of male-biased expression, rather than a failure in the establishment or the extinction of male-biased genes.

【 授权许可】

Unknown   
© Magnusson et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.