Copy Number Variation Affecting the Photoperiod-B1 and Vernalization-A1 Genes Is Associated with Altered Flowering Time in Wheat (Triticum aestivum)
Open Access
- 22 March 2012
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 7 (3), e33234
- https://doi.org/10.1371/journal.pone.0033234
Abstract
The timing of flowering during the year is an important adaptive character affecting reproductive success in plants and is critical to crop yield. Flowering time has been extensively manipulated in crops such as wheat (Triticum aestivum L.) during domestication, and this enables them to grow productively in a wide range of environments. Several major genes controlling flowering time have been identified in wheat with mutant alleles having sequence changes such as insertions, deletions or point mutations. We investigated genetic variants in commercial varieties of wheat that regulate flowering by altering photoperiod response (Ppd-B1 alleles) or vernalization requirement (Vrn-A1 alleles) and for which no candidate mutation was found within the gene sequence. Genetic and genomic approaches showed that in both cases alleles conferring altered flowering time had an increased copy number of the gene and altered gene expression. Alleles with an increased copy number of Ppd-B1 confer an early flowering day neutral phenotype and have arisen independently at least twice. Plants with an increased copy number of Vrn-A1 have an increased requirement for vernalization so that longer periods of cold are required to potentiate flowering. The results suggest that copy number variation (CNV) plays a significant role in wheat adaptation.Keywords
This publication has 35 references indexed in Scilit:
- Multiple reference genomes and transcriptomes for Arabidopsis thalianaNature, 2011
- Targeted analysis of nucleotide and copy number variation by exon capture in allotetraploid wheat genomeGenome Biology, 2011
- Gene copy-number polymorphism in natureProceedings. Biological sciences, 2010
- Origins and functional impact of copy number variation in the human genomeNature, 2009
- Genetic and Molecular Characterization of theVRN2Loci in Tetraploid WheatPlant Physiology, 2008
- The wheat and barley vernalization gene VRN3 is an orthologue of FTProceedings of the National Academy of Sciences of the United States of America, 2006
- Large deletions within the first intron in VRN-1 are associated with spring growth habit in barley and wheatMolecular Genetics and Genomics, 2005
- Characterization and functional analysis of three wheat genes with homology to the CONSTANS flowering time gene in transgenic riceThe Plant Journal, 2003
- Detection of QTLs for heading time and photoperiod response in wheat using a doubled-haploid populationGenome, 2000
- The location of the photoperiod gene, Ppd2 and an additional genetic factor for ear-emergence time on chromosome 2B of wheatHeredity, 1983