title: Expression and interaction of small heat shock proteins (sHsps) in rice in response to heat stress.
abstract: The inherent immobility of rice (Oryza sativa L.) limited their abilities to avoid heat stress and required them to contend with heat stress through innate defense abilities in which heat shock proteins played important roles. In this study, Hsp26.7, Hsp23.2, Hsp17.9A, Hsp17.4 and Hsp16.9A were up-regulated in Nipponbare during seedling and anthesis stages in response to heat stress. Subsequently, the expressing levels of these five sHsps in the heat-tolerant rice cultivar, Co39, were all significantly higher than that in the heat-susceptible rice cultivar, Azucena. This indicated that the expressive level of these five sHsps was positively related to the ability of rice plants to avoid heat stress. Thus, the expression level of these five sHsps can be regarded as bio-markers for screening rice cultivars with different abilities to avoid heat stress. Hsp18.1, Hsp17.9A, Hsp17.7 and Hsp16.9A, in the three rice cultivars under heat stress were found to be involved in one protein complex by Native-PAGE, and the interactions of Hsp18.1 and Hsp 17.7, Hsp18.1 and Hsp 17.9A, and Hsp17.7 and Hsp16.9A were further validated by yeast 2-hybridization. Pull down assay also confirmed the interaction between Hsp17.7 and Hsp16.9A in rice under heat stress. In conclusion, the up-regulation of the 5 sHsps is a key step for rice to tolerate heat stress, after that some sHsps assembled into a large hetero-oligomeric complex. In addition, through protein-protein interaction, Hsp101 regulated thiamine biosynthesis, and Hsp82 homology affected nitrogen metabolism, while Hsp81-1 were involved in the maintenance of sugar or starch synthesis in rice plants under heat stress. These results provide new insight into the regulatory mechanism of sHsps in rice.
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China; Center for Proteomics, State Key Laboratory of Biocontrol, College of Life Sciences, Sun Yat-sen University, Guangzhou 510275, PR China.
authors.forename: Xinhai
authors.initials: X
authors.lastname: Chen
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China; Putian University, Fujian 351100, PR China.
authors.forename: Shoukai
authors.initials: S
authors.lastname: Lin
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
authors.forename: Qiulin
authors.initials: Q
authors.lastname: Liu
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
authors.forename: Jian
authors.initials: J
authors.lastname: Huang
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
authors.forename: Wenfeng
authors.initials: W
authors.lastname: Zhang
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Lin
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
authors.forename: Yongfei
authors.initials: Y
authors.lastname: Wang
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
authors.forename: Yuqin
authors.initials: Y
authors.lastname: Ke
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China. Electronic address: hehq16@gmail.com.
authors.forename: Huaqin
authors.initials: H
authors.lastname: He
mesh_terms: D000222:Adaptation, Physiological; D015415:Biomarkers / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D050888:Heat-Shock Proteins, Small / Q000235:genetics* / Q000378:metabolism; D006358:Hot Temperature; D063347:Native Polyacrylamide Gel Electrophoresis; D009584:Nitrogen / Q000378:metabolism; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D025941:Protein Interaction Mapping; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D055503:Protein Multimerization; D036226:Seedlings / Q000235:genetics* / Q000378:metabolism; D013213:Starch / Q000096:biosynthesis; D013312:Stress, Physiological / Q000235:genetics*; D013831:Thiamine / Q000096:biosynthesis; D020798:Two-Hybrid System Techniques
chemical_list: D015415:Biomarkers; D050888:Heat-Shock Proteins, Small; D010940:Plant Proteins; D020033:Protein Isoforms; D013213:Starch; D009584:Nitrogen; D013831:Thiamine
keywords: Expression; Heat stress; Interaction; Protein complex; Rice (Oryza sativa L.); Small heat shock protein