FUS-NLS/Transportin 1 complex structure provides insights into the nuclear targeting mechanism of FUS and the implications in ALS.
The C-terminal nuclear localization sequence of FUsed in Sarcoma (FUS-NLS) is critical for its nuclear import mediated by transportin (Trn1). Familial amyotrophic lateral sclerosis (ALS) related mutations are clustered in FUS-NLS. We report here the structural, biochemical and cell biological characterization of the FUS-NLS and its clinical implications. The crystal structure of the FUS-NLS/Trn1 complex shows extensive contacts between the two proteins and a unique α-helical structure in the FUS-NLS. The binding affinity between Trn1 and FUS-NLS (wide-type and 12 ALS-associated mutants) was determined. As compared to the wide-type FUS-NLS (K(D) = 1.7 nM), each ALS-associated mutation caused a decreased affinity and the range of this reduction varied widely from 1.4-fold over 700-fold. The affinity of the mutants correlated with the extent of impaired nuclear localization, and more importantly, with the duration of disease progression in ALS patients. This study provides a comprehensive understanding of the nuclear targeting mechanism of FUS and illustrates the significance of FUS-NLS in ALS.
Laboratory of Non-coding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
Chunyan
C
Niu
Jiayu
J
Zhang
Feng
F
Gao
Liuqing
L
Yang
Minze
M
Jia
Haining
H
Zhu
Weimin
W
Gong
D000595:Amino Acid Sequence; D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D011485:Protein Binding; D017433:Protein Structure, Secondary; D034702:RNA-Binding Protein FUS / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D020349:Surface Plasmon Resonance; D028961:beta Karyopherins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*
D034702:RNA-Binding Protein FUS; C108121:TNPO1 protein, human; D028961:beta Karyopherins