Thioredoxin Reductase Type C (NTRC) Orchestrates Enhanced Thermotolerance to Arabidopsis by Its Redox-Dependent Holdase Chaperone Function

被引：77

作者：

Chae, Ho Byoung ^{[1
,2
]}

Moon, Jeong Chan ^{[1
,2
]}

Shin, Mi Rim ^{[1
,2
]}

Chi, Yong Hun ^{[1
,2
]}

Jung, Young Jun ^{[1
,2
]}

Lee, Sun Yong ^{[1
,2
]}

Nawkar, Ganesh M. ^{[1
,2
]}

Jung, Hyun Suk ^{[3
]}

Hyun, Jae Kyung ^{[3
]}

Kim, Woe Yeon ^{[1
,2
]}

Kang, Chang Ho ^{[1
,2
]}

Yun, Dae-Jin ^{[1
,2
]}

Lee, Kyun Oh ^{[1
,2
]}

Lee, Sang Yeol ^{[1
,2
]}

机构：

[1] Gyeongsang Natl Univ, Div Appl Life Sci, Program BK21, 501 Jinju Daero, Jinju 660701, South Korea

[2] Gyeongsang Natl Univ, PMBBRC, Jinju 660701, South Korea

[3] Korea Basic Sci Inst, Div Elect Microscop Res, Taejon 305333, South Korea

来源：

MOLECULAR PLANT | 2013年 / 6卷 / 02期

关键词：

NADPH-thioredoxin reductase type C (NTRC); oligomeric complexes; disulfide reductase; foldase and holdase chaperone functions; redox; thermotolerance; HEAT-SHOCK-PROTEIN; 2-CYS PEROXIREDOXIN; ESCHERICHIA-COLI; GENE; SYSTEM; STRESS; CHLOROPLAST; PEROXIDASE; CRYSTALLIN; TOLERANCE;

D O I：

10.1093/mp/sss105

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Genevestigator analysis has indicated heat shock induction of transcripts for NADPH-thioredoxin reductase, type C (NTRC) in the light. Here we show overexpression of NTRC in Arabidopsis (NTRCE) resulting in enhanced tolerance to heat shock, whereas NTRC knockout mutant plants (ntrc1) exhibit a temperature sensitive phenotype. To investigate the underlying mechanism of this phenotype, we analyzed the proteins biochemical properties and protein structure. NTRC assembles into homopolymeric structures of varying complexity with functions as a disulfide reductase, a foldase chaperone, and as a holdase chaperone. The multiple functions of NTRC are closely correlated with protein structure. Complexes of higher molecular weight (HMW) showed stronger activity as a holdase chaperone, while low molecular weight (LMW) species exhibited weaker holdase chaperone activity but stronger disulfide reductase and foldase chaperone activities. Heat shock converted LMW proteins into HMW complexes. Mutations of the two active site Cys residues of NTRC into Ser (C217/454S-NTRC) led to a complete inactivation of its disulfide reductase and foldase chaperone functions, but conferred only a slight decrease in its holdase chaperone function. The overexpression of the mutated C217/454S-NTRC provided Arabidopsis with a similar degree of thermotolerance compared with that of NTRCE plants. However, after prolonged incubation under heat shock, NTRCE plants tolerated the stress to a higher degree than C217/454S-NTRCE plants. The results suggest that the heat shock-mediated holdase chaperone function of NTRC is responsible for the increased thermotolerance of Arabidopsis and the activity is significantly supported by NADPH.

引用

页码：323 / 336

页数：14

共 51 条

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