Patterns of DNA-sequence divergence between Drosophila miranda and D. pseudoobscura.
Contrary to the classical view, a large amount of non-coding DNA seems to be selectively constrained in Drosophila and other species. Here, using Drosophila miranda BAC sequences and the Drosophila pseudoobscura genome sequence, we aligned coding and non-coding sequences between D. pseudoobscura and D. miranda, and investigated their patterns of evolution. We found two patterns that have previously been observed in comparisons between Drosophila melanogaster and its relatives. First, there is a negative correlation between intron divergence and intron length, suggesting that longer non-coding sequences may contain more regulatory elements than shorter sequences. Our other main finding is a negative correlation between the rate of non-synonymous substitutions (d(N)) and codon usage bias (F(op)), showing that fast-evolving genes have a lower codon usage bias, consistent with strong positive selection interfering with weak selection for codon usage.
Institute of Evolutionary Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3JT, UK. s0677532@sms.ed.ac.uk
Sophie
S
Marion de Procé
Daniel L
DL
Halligan
Peter D
PD
Keightley
Brian
B
Charlesworth
D000818:Animals; D001483:Base Sequence / Q000235:genetics*; D022202:Chromosomes, Artificial, Bacterial; D003062:Codon / Q000235:genetics; D004330:Drosophila / Q000145:classification / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics; D019143:Evolution, Molecular; D015723:Gene Library; D049750:Genome, Insect; D007438:Introns; D008297:Male; D016415:Sequence Alignment; D013045:Species Specificity; D020506:Untranslated Regions / Q000235:genetics
D003062:Codon; D029721:Drosophila Proteins; D020506:Untranslated Regions