Characterization and adaptive evolution of α-tubulin genes in the Miscanthus sinensis complex (Poaceae)

W. U. Wen-Luan, Barbara A. Schaal, Chung Yu Hwang, Ming Der Hwang, Y. U.Chung Chiang, Tzen Yuh Chiang

Research output: Contribution to journalArticlepeer-review

5 Scopus citations

Abstract

To investigate the organization of and mode of selection in the α-tubulin genes, full-length α-tubulin genes were cloned from four intraspecific taxa of Miscanthus sinensis and its close relatives M. floridulus and M. condensatus using standard polymerase chain reaction (PCR) and rapid amplification of genomic ends (RAGE)-PCR strategies. Genealogical analysis of angiosperms recovered a monophyletic group of Miscanthus α-tubulin genes, which is homologous to the tua5 locus of maize. Two clusters of nearly equal frequency revealed paraphyly within each Miscanthus taxon. Between-cluster recombination was frequent. Additional evidence for cooccurrence of two haplotypes within individuals and a large-scale crossover all suggested a likely allelic relationship between the Miscanthus clusters. Given a long between-species divergence time in Miscanthus, wide occurrence of the trans-species polymorphisms in α-tubulin genes and the approximately equal frequency of each allelic type make it extremely unlikely that α-tubulin diversity has been maintained under neutrality. Balancing selection may have contributed to such an apportioning of genetic variability as well as to high levels of genetic variation in α-tubulin and higher substitution rates at synonymous sites of exons than at intron bases of M. sinensis. In addition, certain effects of demographic oscillation may have distorted the scenario of a functional locus operating under balancing selection.

Original languageEnglish
Pages (from-to)1513-1521
Number of pages9
JournalAmerican Journal of Botany
Volume90
Issue number10
DOIs
StatePublished - Oct 2003

Keywords

  • Allelic recombination
  • Balancing selection
  • Demographic history
  • Miscanthus sinensis complex
  • Poaceae
  • Trans-species polymorphisms
  • α-tubulin

Fingerprint

Dive into the research topics of 'Characterization and adaptive evolution of α-tubulin genes in the Miscanthus sinensis complex (Poaceae)'. Together they form a unique fingerprint.

Cite this