Differential evolutionary dynamics of duplicated paralogous Adh loci in allotetraploid cotton (Gossypium).
Levels and patterns of nucleotide diversity vary widely among lineages. Because allopolyploid species contain duplicated (homoeologous) genes, studies of nucleotide diversity at homoeologous loci may facilitate insight into the evolutionary dynamics of duplicated loci. In this study, we describe patterns of sequence diversity from an alcohol dehydrogenase homoeologous locus pair (AdhC) in allotetraploid cotton (Gossypium, Malvaceae). These data are compared with equivalent information from another homoeologous alcohol dehydrogenase gene pair (AdhA, Small, Ryburn, and Wendel 1999. Mol. Biol. Evol. 16:491-501) which has an overall slower evolutionary rate than AdhC. As expected from the predicted correlation between nucleotide diversity and evolutionary rate, nucleotide diversity was higher for AdhC than for AdhA. In addition, nucleotide diversity is higher in the D-subgenome of allotetraploid cotton for AdhC, confirming earlier observations for AdhA. These observations indicate that for these two pairs of Adh loci, the null hypothesis of equivalent evolutionary dynamics for duplicated genes in allotetraploid cotton is rejected.
Small
Randall L
RL
Department of Botany, 437 Hesler Biology, The University of Tennessee, Knoxville, TN 37996-1100, USA. rsmall@utk.edu
Wendel
Jonathan F
JF
D000426:Alcohol Dehydrogenase / Q000235:genetics*; D000429:Alcohol Oxidoreductases / Q000235:genetics; D001483:Base Sequence; D018744:DNA, Plant / Q000235:genetics; D019143:Evolution, Molecular; D020440:Gene Duplication; D017343:Genes, Plant; D014644:Genetic Variation; D016680:Genome, Bacterial; D003368:Gossypium / Q000145:classification / Q000201:enzymology* / Q000235:genetics*; D008957:Models, Genetic; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D011123:Polyploidy; D012689:Sequence Homology, Nucleic Acid; D013045:Species Specificity
D018744:DNA, Plant; D000429:Alcohol Oxidoreductases; D000426:Alcohol Dehydrogenase