|
|
||||||||
|
Plant Physiology Preview Published on November 16, 2007; 10.1104/pp.107.108852
OPEN ACCESS ARTICLE
Received September 10, 2007 Recurrent Deletions of Puroindoline Genes at the Grain Hardness Locus in Four Independent Lineages of Polyploid Wheat
Wheat Genetic and Genomic Resources Center, Department of Plant Pathology, 4024 Throckmorton Hall, Kansas State University, Manhattan, KS 66506-5502 * Corresponding author; email: wli{at}ksu.edu.
Polyploidy is known to induce numerous genetic and epigenetic changes but little is known about their physiological bases. In wheat, grain texture is mainly determined by the hardness (Ha) locus consisting of genes Pina and Pinb. These genes are conserved in diploid progenitors but were deleted from the A and B genomes of tetraploid Triticum turgidum (AB). We now report the recurrent deletions of Pina-Pinb in other lineages of polyploid wheat. We analyzed the Ha haplotype structure in 90 diploid and 300 polyploid accessions of Triticum and Aegilops species. Pin genes were conserved in all diploid species and deletion haplotypes were detected in all polyploid Triticum and most of the polyploid Aegilops species. Two Pina-Pinb deletion haplotypes were found in hexaploid T. aestivum (ABD). Pina and Pinb were eliminated from the G genome, but maintained in the A genome of tetraploid T. timopheevii (AG). Subsequently, Pina and Pinb were deleted from the A genome but retained in the Am genome of hexaploid T. zhukovskyi (AmAG). Comparison of deletion breakpoints demonstrated that the Pina-Pinb deletion occurred independently and recurrently in the four polyploid wheat species. The implications of Pina-Pinb deletions for polyploid-driven evolution of gene and genome and its possible physiological significance are discussed.
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| ASPB Publications | PLANT PHYSIOLOGY | THE PLANT CELL | |
|---|---|---|---|