title: SUMO E3 Ligases GmSIZ1a and GmSIZ1b regulate vegetative growth in soybean .
abstract: SIZ1 is a small ubiquitin-related modifier (SUMO) E3 ligase that mediates post-translational SUMO modification of target proteins and thereby regulates developmental processes and hormonal and environmental stress responses in Arabidopsis. However, the role of SUMO E3 ligases in crop plants is largely unknown. Here, we identified and characterized two Glycine max (soybean) SUMO E3 ligases, GmSIZ1a and GmSIZ1b. Expression of GmSIZ1a and GmSIZ1b was induced in response to salicylic acid (SA), heat, and dehydration treatment, but not in response to cold, abscisic acid (ABA), and NaCl treatment. Although GmSIZ1a was expressed at higher levels than GmSIZ1b, both genes encoded proteins with SUMO E3 ligase activity in vivo. Heterologous expression of GmSIZ1a or GmSIZ1b rescued the mutant phenotype of Arabidopsis siz1-2, including dwarfism, constitutively activated expression of pathogen-related genes, and ABA-sensitive seed germination. Simultaneous downregulation of GmSIZ1a and GmSIZ1b (GmSIZ1a/b) using RNA interference (RNAi)-mediated gene silencing decreased heat shock-induced SUMO conjugation in soybean. Moreover, GmSIZ1RNAi plants exhibited reduced plant height and leaf size. However, unlike Arabidopsis siz1-2 mutant plants, flowering time and SA levels were not significantly altered in GmSIZ1RNAi plants. Taken together, our results indicate that GmSIZ1a and GmSIZ1b mediate SUMO modification and positively regulate vegetative growth in soybean.
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Cai
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Xiangxiong
authors.initials: X
authors.lastname: Kong
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Zhong
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Suli
authors.initials: S
authors.lastname: Sun
authors.affiliation: Department of Ornamental Horticulture, China Agricultural University, Beijing 100193, China.
authors.forename: Xiao Feng
authors.initials: XF
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Yin Hua
authors.initials: YH
authors.lastname: Jin
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Youning
authors.initials: Y
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Agricultural Microbiology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China.
authors.forename: Xia
authors.initials: X
authors.lastname: Li
authors.affiliation: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
authors.forename: Zhendong
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Plant Molecular Physiology, Institute of Botany, The Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Jing Bo
authors.initials: JB
authors.lastname: Jin
mesh_terms: D002467:Cell Nucleus / Q000378:metabolism; D015536:Down-Regulation / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D018515:Plant Leaves / Q000033:anatomy & histology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D060888:Real-Time Polymerase Chain Reaction; D020156:Salicylic Acid / Q000378:metabolism; D013025:Glycine max / Q000033:anatomy & histology / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development*; D013347:Subcellular Fractions / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D044767:Ubiquitin-Protein Ligases; D020156:Salicylic Acid
keywords: SIZ1; SUMO; SUMO E3 ligase; soybean; vegetative growth