Evolution of X-Linked Male-Biased Genes in Drosophila
Published Online: 15 JUL 2014
Copyright © 2001 John Wiley & Sons, Ltd. All rights reserved.
How to Cite
Herrig, D. K. and Llopart, A. 2014. Evolution of X-Linked Male-Biased Genes in Drosophila. eLS. .
- Published Online: 15 JUL 2014
Sex chromosomes, particularly the X chromosome, play a unique role in evolution due to several distinct features. In Drosophila, the X chromosome has been proposed to constitute an undesirable environment for genes expressed at higher levels in males than in females (i.e. male-biased genes) and, as a result, is partially demasculinized. However, male-biased genes remaining on the X chromosome do not seem to be at a disadvantage relative to their autosomal counterparts. Population genetic models predict that under certain conditions X-linked genes will experience more bouts of positive selection than autosomal genes, leading to faster-X evolution, particularly for male-biased genes. As theory posits, Drosophila X-linked male-biased genes show evidence of adaptive evolution at both protein and expression levels. This faster-X evolution has broad implications. In speciation, it may contribute to explain why the X chromosome is a hotspot for the genetic factors underlying hybrid male sterility (i.e. the large X-effect).
Underrepresentation of X-linked male-biased genes due to unfavorable features of the X chromosome.
Faster-X evolution of male-biased genes at both the protein and expression levels.
Consequences of faster-X evolution include the disproportionally large effect of the X chromosome in hybrid male sterility.
- X chromosome;
- sexual antagonism;
- meiotic sex chromosome inactivation;
- dosage compensation;
- gene expression;
- large X-effect;
- adaptive evolution;
- positive selection