title: Molecular basis of a shattering resistance boosting global dissemination of soybean.
abstract: Pod dehiscence (shattering) is essential for the propagation of wild plant species bearing seeds in pods but is a major cause of yield loss in legume and crucifer crops. Although natural genetic variation in pod dehiscence has been, and will be, useful for plant breeding, little is known about the molecular genetic basis of shattering resistance in crops. Therefore, we performed map-based cloning to unveil a major quantitative trait locus (QTL) controlling pod dehiscence in soybean. Fine mapping and complementation testing revealed that the QTL encodes a dirigent-like protein, designated as Pdh1. The gene for the shattering-resistant genotype, pdh1, was defective, having a premature stop codon. The functional gene, Pdh1, was highly expressed in the lignin-rich inner sclerenchyma of pod walls, especially at the stage of initiation in lignin deposition. Comparisons of near-isogenic lines indicated that Pdh1 promotes pod dehiscence by increasing the torsion of dried pod walls, which serves as a driving force for pod dehiscence under low humidity. A survey of soybean germplasm revealed that pdh1 was frequently detected in landraces from semiarid regions and has been extensively used for breeding in North America, the world's leading soybean producer. These findings point to a new mechanism for pod dehiscence involving the dirigent protein family and suggest that pdh1 has played a crucial role in the global expansion of soybean cultivation. Furthermore, the orthologs of pdh1, or genes with the same role, will possibly be useful for crop improvement.
authors.affiliation: Crop Cold Tolerance Research Team, NARO (National Agricultural Research Organization) Hokkaido Agricultural Research Center, Hitsujigaoka 1, Toyohira-ku, Sapporo 062-8555, Japan; Department of Planning and General Administration, NARO Western Region Agricultural Research Center, 6-12-1, Nishifukatsu-cho, Fukuyama 721-8514, Japan; funazki@affrc.go.jp kaien@res.agr.hokudai.ac.jp.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Funatsuki
authors.affiliation: Graduate School of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan;
authors.forename: Masaya
authors.initials: M
authors.lastname: Suzuki
authors.affiliation: Crop Cold Tolerance Research Team, NARO (National Agricultural Research Organization) Hokkaido Agricultural Research Center, Hitsujigaoka 1, Toyohira-ku, Sapporo 062-8555, Japan;
authors.forename: Aya
authors.initials: A
authors.lastname: Hirose
authors.affiliation: Graduate School of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan;
authors.forename: Hiroki
authors.initials: H
authors.lastname: Inaba
authors.affiliation: Field Crop Research Division, NARO Institute of Crop Science, 2-1-18, Kannondai, Tsukuba 305-8518, Japan;
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yamada
authors.affiliation: Field Crop Research Division, NARO Institute of Crop Science, 2-1-18, Kannondai, Tsukuba 305-8518, Japan;
authors.forename: Makita
authors.initials: M
authors.lastname: Hajika
authors.affiliation: Crop Cold Tolerance Research Team, NARO (National Agricultural Research Organization) Hokkaido Agricultural Research Center, Hitsujigaoka 1, Toyohira-ku, Sapporo 062-8555, Japan;
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Komatsu
authors.affiliation: Faculty of Agriculture, Kagawa University, 2393 Ikenobe, Miki-cho, Kagawa 761-0795, Japan; and.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Katayama
authors.affiliation: Crop Cold Tolerance Research Team, NARO (National Agricultural Research Organization) Hokkaido Agricultural Research Center, Hitsujigaoka 1, Toyohira-ku, Sapporo 062-8555, Japan; Agrogenomics Research Center, National Institute of Agrobiological Sciences, 2-1-2, Kannondai, Tsukuba 305-0856, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Sayama
authors.affiliation: Crop Cold Tolerance Research Team, NARO (National Agricultural Research Organization) Hokkaido Agricultural Research Center, Hitsujigaoka 1, Toyohira-ku, Sapporo 062-8555, Japan; Agrogenomics Research Center, National Institute of Agrobiological Sciences, 2-1-2, Kannondai, Tsukuba 305-0856, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Ishimoto
authors.affiliation: Graduate School of Agriculture, Hokkaido University, Kita 9, Nishi 9, Kita-ku, Sapporo 060-8589, Japan; funazki@affrc.go.jp kaien@res.agr.hokudai.ac.jp.
authors.forename: Kaien
authors.initials: K
authors.lastname: Fujino
mesh_terms: D001483:Base Sequence; D001947:Breeding / Q000379:methods*; D003001:Cloning, Molecular; D019295:Computational Biology; D005638:Fruit / Q000235:genetics / Q000502:physiology*; D017343:Genes, Plant / Q000235:genetics*; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010802:Phylogeny; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D040641:Quantitative Trait Loci; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D058614:Seed Dispersal / Q000235:genetics*; D017422:Sequence Analysis, DNA; D013025:Glycine max / Q000235:genetics*
keywords: QTL; crop improvement; dirigent protein; map-based cloning; pod dehiscence