RRC ID 36130
Author Nakamura S, Pourkheirandish M, Morishige H, Kubo Y, Nakamura M, Ichimura K, Seo S, Kanamori H, Wu J, Ando T, Hensel G, Sameri M, Stein N, Sato K, Matsumoto T, Yano M, Komatsuda T.
Title Mitogen-Activated Protein Kinase Kinase 3 Regulates Seed Dormancy in Barley.
Journal Curr Biol
Abstract Seed dormancy has fundamental importance in plant survival and crop production; however, the mechanisms regulating dormancy remain unclear [1-3]. Seed dormancy levels generally decrease during domestication to ensure that crops successfully germinate in the field. However, reduction of seed dormancy can cause devastating losses in cereals like wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) due to pre-harvest sprouting, the germination of mature seed (grain) on the mother plant when rain occurs before harvest. Understanding the mechanisms of dormancy can facilitate breeding of crop varieties with the appropriate levels of seed dormancy [4-8]. Barley is a model crop [9, 10] and has two major seed dormancy quantitative trait loci (QTLs), SD1 and SD2, on chromosome 5H [11-19]. We detected a QTL designated Qsd2-AK at SD2 as the single major determinant explaining the difference in seed dormancy between the dormant cultivar "Azumamugi" (Az) and the non-dormant cultivar "Kanto Nakate Gold" (KNG). Using map-based cloning, we identified the causal gene for Qsd2-AK as Mitogen-activated Protein Kinase Kinase 3 (MKK3). The dormant Az allele of MKK3 is recessive; the N260T substitution in this allele decreases MKK3 kinase activity and appears to be causal for Qsd2-AK. The N260T substitution occurred in the immediate ancestor allele of the dormant allele, and the established dormant allele became prevalent in barley cultivars grown in East Asia, where the rainy season and harvest season often overlap. Our findings show fine-tuning of seed dormancy during domestication and provide key information for improving pre-harvest sprouting tolerance in barley and wheat.
Volume 26(6)
Pages 775-81
Published 2016-3-21
DOI 10.1016/j.cub.2016.01.024
PII S0960-9822(16)00074-9
PMID 26948880
MeSH Amino Acid Substitution Asia, Southeastern Biological Evolution Cloning, Molecular Gene Expression Regulation, Plant Hordeum / genetics Hordeum / physiology* MAP Kinase Kinase 3 / genetics MAP Kinase Kinase 3 / metabolism* Mutation Plant Dormancy / genetics* Plant Dormancy / physiology Plant Proteins / genetics Plant Proteins / metabolism* Quantitative Trait Loci
IF 9.193
Times Cited 34
WOS Category BIOCHEMISTRY & MOLECULAR BIOLOGY CELL BIOLOGY
Resource
Barley