Genetics, Vol. 177, 359-374, September 2007, Copyright © 2007
doi:10.1534/genetics.107.077081

Evolution of Gene Sequence in Response to Chromosomal Location

Department of Biology, University of Utah, Salt Lake City, Utah 84112

1 Corresponding author: Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112.
E-mail: diazcastillo{at}biology.utah.edu

Evolutionary forces acting on the repetitive DNA of heterochromatin are not constrained by the same considerations that apply to protein-coding genes. Consequently, such sequences are subject to rapid evolutionary change. By examining the Troponin C gene family of Drosophila melanogaster, which has euchromatic and heterochromatic members, we find that protein-coding genes also evolve in response to their chromosomal location. The heterochromatic members of the family show a reduced CG content and increased variation in DNA sequence. We show that the CG reduction applies broadly to the protein-coding sequences of genes located at the heterochromatin:euchromatin interface, with a very strong correlation between CG content and the distance from centric heterochromatin. We also observe a similar trend in the transition from telomeric heterochromatin to euchromatin. We propose that the methylation of DNA is one of the forces driving this sequence evolution.




This article has been cited by other articles:


Home page
Biol LettHome page
P. R Haddrill and B. Charlesworth
Non-neutral processes drive the nucleotide composition of non-coding sequences in Drosophila
Biol Lett, August 23, 2008; 4(4): 438 - 441.
[Abstract] [Full Text] [PDF]