RRC ID 2076
Author Komatsuda T, Pourkheirandish M, He C, Azhaguvel P, Kanamori H, Perovic D, Stein N, Graner A, Wicker T, Tagiri A, Lundqvist U, Fujimura T, Matsuoka M, Matsumoto T, Yano M.
Title Six-rowed barley originated from a mutation in a homeodomain-leucine zipper I-class homeobox gene.
Journal Proc Natl Acad Sci U S A
Abstract Increased seed production has been a common goal during the domestication of cereal crops, and early cultivators of barley (Hordeum vulgare ssp. vulgare) selected a phenotype with a six-rowed spike that stably produced three times the usual grain number. This improved yield established barley as a founder crop for the Near Eastern Neolithic civilization. The barley spike has one central and two lateral spikelets at each rachis node. The wild-type progenitor (H. vulgare ssp. spontaneum) has a two-rowed phenotype, with additional, strictly rudimentary, lateral rows; this natural adaptation is advantageous for seed dispersal after shattering. Until recently, the origin of the six-rowed phenotype remained unknown. In the present study, we isolated vrs1 (six-rowed spike 1), the gene responsible for the six-rowed spike in barley, by means of positional cloning. The wild-type Vrs1 allele (for two-rowed barley) encodes a transcription factor that includes a homeodomain with a closely linked leucine zipper motif. Expression of Vrs1 was strictly localized in the lateral-spikelet primordia of immature spikes, suggesting that the VRS1 protein suppresses development of the lateral rows. Loss of function of Vrs1 resulted in complete conversion of the rudimentary lateral spikelets in two-rowed barley into fully developed fertile spikelets in the six-rowed phenotype. Phylogenetic analysis demonstrated that the six-rowed phenotype originated repeatedly, at different times and in different regions, through independent mutations of Vrs1.
Volume 104(4)
Pages 1424-9
Published 2007-1-23
DOI 10.1073/pnas.0608580104
PII 0608580104
PMID 17220272
PMC PMC1783110
MeSH Base Sequence Biological Evolution Cloning, Molecular DNA Primers Genes, Homeobox* Genes, Plant* Hordeum / genetics* Leucine Zippers* Molecular Sequence Data Mutation*
IF 9.412
Times Cited 320
Barley E527 I335 J247 U049 T637 E832 U013 C059 B327 U316 U607 K735