TITLE

Global patterns of sequence evolution in Drosophila

AUTHOR(S)
Gallach, Miguel; Arnau, Vicente; Marin, Ignacio
PUB. DATE
January 2007
SOURCE
BMC Genomics;2007, Vol. 8, p1
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Background: Sequencing of the genomes of several Drosophila allows for the first precise analyses of how global sequence patterns change among multiple, closely related animal species. A basic question is whether there are characteristic features that differentiate chromosomes within a species or between different species. Results: We explored the euchromatin of the chromosomes of seven Drosophila species to establish their global patterns of DNA sequence diversity. Between species, differences in the types and amounts of simple sequence repeats were found. Within each species, the autosomes have almost identical oligonucleotide profiles. However, X chromosomes and autosomes have, in all species, a qualitatively different composition. The X chromosomes are less complex than the autosomes, containing both a higher amount of simple DNA sequences and, in several cases, chromosome-specific repetitive sequences. Moreover, we show that the right arm of the X chromosome of Drosophila pseudoobscura, which evolved from an autosome 10 - 18 millions of years ago, has a composition which is identical to that of the original, left arm of the X chromosome. Conclusion: The consistent differences among species, differences among X chromosomes and autosomes and the convergent evolution of X and neo-X chromosomes demonstrate that strong forces are acting on drosophilid genomes to generate peculiar chromosomal landscapes. We discuss the relationships of the patterns observed with differential recombination and mutation rates and with the process of dosage compensation.
ACCESSION #
28858918

 

Related Articles

Share

Read the Article

Courtesy of THE LIBRARY OF VIRGINIA

Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics