title: Characterization of heat shock cognate protein 70 gene and its differential expression in response to thermal stress between two wing morphs of Nilaparvata lugens (Stål).
abstract: Previous studies have demonstrated differences in thermotolerance between two wing morphs of Nilaparvata lugens, the most serious pest of rice across the Asia. To reveal the molecular regulatory mechanisms underlying the differential thermal resistance abilities between two wing morphs, a full-length of transcript encoding heat shock cognate protein 70 (Hsc70) was cloned, and its expression patterns across temperature gradients were analyzed. The results showed that the expression levels of NlHsc70 in macropters increased dramatically after heat shock from 32 to 38°C, while NlHsc70 transcripts in brachypters remained constant under different temperature stress conditions. In addition, NlHsc70 expression in the macropters was significantly higher than that in brachypters at 1 and 2h recovery from 40°C heat shock. There was no significant difference in NlHsc70 mRNA expression between brachypters and macropters under cold shock conditions. Therefore, NlHsc70 was indeed a constitutively expressed member of the Hsp70 family in brachypters of N. lugens, while it was heat-inducible in macropters. Furthermore, the survival rates of both morphs injected with NlHsc70 dsRNA were significantly decreased following heat shock at 40°C or cold shock at 0°C for 1h. These results suggested that the up-regulation of NlHsc70 is possibly related to the thermal resistance, and the more effective inducement expression of NlHsc70 in macropters promotes a greater thermal tolerance under temperature stress conditions.
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China; State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, PR China.
authors.forename: Kai
authors.initials: K
authors.lastname: Lu
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
authors.forename: Xia
authors.initials: X
authors.lastname: Chen
authors.affiliation: College of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, PR China.
authors.forename: Wenting
authors.initials: W
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, PR China. Electronic address: lsszhou@mail.sysu.edu.cn.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhou
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D000818:Animals; D003001:Cloning, Molecular; D005260:Female; D020869:Gene Expression Profiling / Q000379:methods*; D018507:Gene Expression Regulation, Developmental; D050883:HSC70 Heat-Shock Proteins / Q000235:genetics*; D006430:Hemiptera / Q000235:genetics* / Q000254:growth & development; D019476:Insect Proteins / Q000235:genetics*; D008297:Male; D009758:Nymph / Q000254:growth & development / Q000378:metabolism; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D013312:Stress, Physiological; D016019:Survival Analysis; D013696:Temperature
chemical_list: D050883:HSC70 Heat-Shock Proteins; D019476:Insect Proteins
keywords: Hsc70; Hsp; Nilaparvata lugens; RNAi; Thermal stress