View : 18 Download: 0

Structural similarity of wild-type and ALS-mutant superoxide dismutase-1 fibrils using limited proteolysis and atomic force microscopy

Title
Structural similarity of wild-type and ALS-mutant superoxide dismutase-1 fibrils using limited proteolysis and atomic force microscopy
Authors
Chan P.K.Chattopadhyay M.Sharma S.Souda P.Gralla E.B.Borchelt D.R.Whitelegge J.P.Valentine J.S.
Ewha Authors
Joan S. Valentine
SCOPUS Author ID
Joan S. Valentinescopus
Issue Date
2013
Journal Title
Proceedings of the National Academy of Sciences of the United States of America
ISSN
0027-8424JCR Link
Citation
vol. 110, no. 27, pp. 10934 - 10939
Indexed
SCI; SCIE; SCOPUS WOS scopus
Abstract
Abnormal assemblies formed by misfolded superoxide dismutase-1 (SOD1) proteins are the likely cause of SOD1-linked familial amyotrophic lateral sclerosis (fALS) and may be involved in some cases of sporadic ALS. To analyze the structure of the insoluble SOD1 amyloid fibrils, we first used limited proteolysis followed by mass spectrometric analysis. Digestion of amyloid fibrils formed from full-length N-acetylated WT SOD1 with trypsin, chymotrypsin, or Pronase revealed that the first 63 residues of the N terminus were protected from protease digestion by fibril formation. Furthermore, every tested ALS-mutant SOD1 protein (G37R, L38V, G41D, G93A, G93S, and D101N) showed a similar protected fragment after trypsin digestion. Our second approach to structural characterization used atomic force microscopy to image the SOD1 fibrils and revealed that WT and mutants showed similar twisted morphologies. WT fibrils had a consistent average helical pitch distance of 62.1 nm. The ALS-mutant SOD1 proteins L38V, G93A, and G93S formed fibrils with helical twist patterns very similar to those of WT, where as small but significant structural deviations were observed for the mutant proteins G37R, G41D, and D101N. Overall, our studies suggest that human WT SOD1 and ALS-mutants tested have a common intrinsic propensity to fibrillate through the N terminus and that single amino acid substitutions can lead to changes in the helical twist pattern.
DOI
10.1073/pnas.1309613110
Appears in Collections:
일반대학원 > 바이오융합과학과 > Journal papers
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE