title: Soybean DREB1/CBF-type transcription factors function in heat and drought as well as cold stress-responsive gene expression.
abstract: Soybean (Glycine max) is a globally important crop, and its growth and yield are severely reduced by abiotic stresses, such as drought, heat, and cold. The cis-acting element DRE (dehydration-responsive element)/CRT plays an important role in activating gene expression in response to these stresses. The Arabidopsis DREB1/CBF genes that encode DRE-binding proteins function as transcriptional activators in the cold stress responsive gene expression. In this study, we identified 14 DREB1-type transcription factors (GmDREB1s) from a soybean genome database. The expression of most GmDREB1 genes in soybean was strongly induced by a variety of abiotic stresses, such as cold, drought, high salt, and heat. The GmDREB1 proteins activated transcription via DREs (dehydration-responsive element) in Arabidopsis and soybean protoplasts. Transcriptome analyses using transgenic Arabidopsis plants overexpressing GmDREB1s indicated that many of the downstream genes are cold-inducible and overlap with those of Arabidopsis DREB1A. We then comprehensively analyzed the downstream genes of GmDREB1B;1, which is closely related to DREB1A, using a transient expression system in soybean protoplasts. The expression of numerous genes induced by various abiotic stresses were increased by overexpressing GmDREB1B;1 in soybean, and DREs were the most conserved element in the promoters of these genes. The downstream genes of GmDREB1B;1 included numerous soybean-specific stress-inducible genes that encode an ABA receptor family protein, GmPYL21, and translation-related genes, such as ribosomal proteins. We confirmed that GmDREB1B;1 directly activates GmPYL21 expression and enhances ABRE-mediated gene expression in an ABA-independent manner. These results suggest that GmDREB1 proteins activate the expression of numerous soybean-specific stress-responsive genes under diverse abiotic stress conditions.
authors.affiliation: Laboratory of Plant Molecular Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, 113-8657, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Kidokoro
authors.forename: Keitaro
authors.initials: K
authors.lastname: Watanabe
authors.forename: Teppei
authors.initials: T
authors.lastname: Ohori
authors.forename: Takashi
authors.initials: T
authors.lastname: Moriwaki
authors.forename: Kyonoshin
authors.initials: K
authors.lastname: Maruyama
authors.forename: Junya
authors.initials: J
authors.lastname: Mizoi
authors.forename: Nang
authors.initials: N
authors.lastname: Myint Phyu Sin Htwe
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Fujita
authors.forename: Sachiko
authors.initials: S
authors.lastname: Sekita
authors.forename: Kazuo
authors.initials: K
authors.lastname: Shinozaki
authors.forename: Kazuko
authors.initials: K
authors.lastname: Yamaguchi-Shinozaki
mesh_terms: D017360:Arabidopsis / Q000235:genetics; D058639:Cold-Shock Response / Q000235:genetics*; D018506:Gene Expression Regulation, Plant; D018869:Heat-Shock Response / Q000235:genetics*; D010802:Phylogeny; D030821:Plants, Genetically Modified / Q000378:metabolism / Q000502:physiology; D013025:Glycine max / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D014157:Transcription Factors
keywords: DREB1/CBF-type transcription factors; PYL family gene; abiotic stress; downstream genes; soybean; translation-related genes