A novel mechanism for small heat shock proteins to function as molecular chaperones.
Small heat shock proteins (sHSPs) are molecular chaperones ubiquitously present in all forms of life, but their function mechanisms remain controversial. Here we show by cryo-electron microscopy and single particle 3D reconstruction that, at the low temperatures (4-25°C), CeHSP17 (a sHSP from Caenorhabditis elegans) exists as a 24-subunit spherical oligomer with tetrahedral symmetry. Our studies demonstrate that CeHSP17 forms large sheet-like super-molecular assemblies (SMAs) at the high temperatures (45-60°C), and such SMAs are apparently the form that exhibits chaperone-like activity. Our findings suggest a novel molecular mechanism for sHSPs to function as molecular chaperones.
Department of Biophysics, College of Basic Medical Sciences, Peking University Health Science Centre, Beijing 100191, China.
Kaiming
K
Zhang
State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China.
Anastasia N
AN
Ezemaduka
Department of Biophysics, College of Basic Medical Sciences, Peking University Health Science Centre, Beijing 100191, China.
Zhao
Z
Wang
Department of Biophysics, College of Basic Medical Sciences, Peking University Health Science Centre, Beijing 100191, China.
Hongli
H
Hu
State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China.
Xiaodong
X
Shi
Department of Biophysics, College of Basic Medical Sciences, Peking University Health Science Centre, Beijing 100191, China.
Chuang
C
Liu
School of Life Sciences, Tsinghua University, Beijing 100084, China.
Xinping
X
Lu
1] State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China [2] Centre for Protein Science, Peking University, Beijing. 100871, China.
Xinmiao
X
Fu
1] State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China [2] Centre for Protein Science, Peking University, Beijing. 100871, China.
Zengyi
Z
Chang
1] Department of Biophysics, College of Basic Medical Sciences, Peking University Health Science Centre, Beijing 100191, China [2] Centre for Protein Science, Peking University, Beijing. 100871, China.
Chang-Cheng
CC
Yin
D000220:Adaptation, Biological; D000818:Animals; D017173:Caenorhabditis elegans; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D050888:Heat-Shock Proteins, Small / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000235:genetics* / Q000378:metabolism; D066329:Protein Aggregates; D011485:Protein Binding; D011487:Protein Conformation; D011994:Recombinant Proteins; D013696:Temperature
D050888:Heat-Shock Proteins, Small; D018832:Molecular Chaperones; D066329:Protein Aggregates; D011994:Recombinant Proteins