@article{faf667f57e7344c2ab7d5c24ebba5d5f,
title = "Maturation of the functional mouse CRES amyloid from globular form",
abstract = "The epididymal lumen contains a complex cystatin-rich nonpathological amyloid matrix with putative roles in sperm maturation and sperm protection. Given our growing understanding for the biological function of this and other functional amyloids, the problem still remains: how functional amyloids assemble including their initial transition to early oligomeric forms. To examine this, we developed a protocol for the purification of nondenatured mouse CRES, a component of the epididymal amyloid matrix, allowing us to examine its assembly to amyloid under conditions that may mimic those in vivo. Herein we use X-ray crystallography, solution-state NMR, and solid-state NMR to follow at the atomic level the assembly of the CRES amyloidogenic precursor as it progressed from monomeric folded protein to an advanced amyloid. We show the CRES monomer has a typical cystatin fold that assembles into highly branched amyloid matrices, comparable to those in vivo, by forming β-sheet assemblies that our data suggest occur via two distinct mechanisms: a unique conformational switch of a highly flexible disulfide-anchored loop to a rigid β-strand and by traditional cystatin domain swapping. Our results provide key insight into our understanding of functional amyloid assembly by revealing the earliest structural transitions from monomer to oligomer and by showing that some functional amyloid structures may be built by multiple and distinctive assembly mechanisms.",
keywords = "Amyloid, Cystatin, NMR spectroscopy, X-ray crystallography",
author = "Aveline Hewetson and Khan, {Nazmul H.} and Dominguez, {Matthew J.} and Do, {Hoa Quynh} and Kusko, {R. E.} and Borcik, {Collin G.} and Rigden, {Daniel J.} and Keegan, {Ronan M.} and {Bryan Sutton}, R. and Latham, {Michael P.} and Wylie, {Benjamin J.} and Cornwall, {Gail A.}",
note = "Funding Information: We thank Masoud Zabet of the Texas Tech University (TTU) Proteomics core for the mass spectrophotometric analysis of CRES isoforms and the preparation of SI Appendix, Fig. S1B. We acknowledge the High Performance Computing (HPC) Center at TTU at Lubbock for providing HPC resources that have contributed to the research results reported within this paper (www.depts.ttu.edu/hpcc/). Use of the Stanford Synchrotron Radiation Lightsource (SSRL), SLAC National Accelerator Laboratory, is supported by the US Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences under Contract DE-AC02-76SF00515. The SSRL Structural Molecular Biology Program is supported by the DOE Office of Biological and Environmental Research, and by the National Institutes of Health, National Institute of General Medical Sciences (NIGMS) (P41GM103393). The contents of this publication are solely the responsibility of the authors and do not necessarily represent the official views of NIGMS or NIH. This work was supported by TTU Health Sciences Center; the Wilson Foundation; the Newby Family (G.A.C.); and NIH Grants R01AR063634 (R.B.S.), 1R35GM128906 (M.P.L.), and 1R35GM124979 (B.J.W.). Funding Information: ACKNOWLEDGMENTS. We thank Masoud Zabet of the Texas Tech University (TTU) Proteomics core for the mass spectrophotometric analysis of CRES isoforms and the preparation of SI Appendix, Fig. S1B. We acknowledge the High Performance Computing (HPC) Center at TTU at Lubbock for providing HPC resources that have contributed to the research results reported within this paper (www.depts.ttu.edu/hpcc/). Use of the Stanford Synchrotron Radiation Lightsource (SSRL), SLAC National Accelerator Laboratory, is supported by the US Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences under Contract DE-AC02-76SF00515. The SSRL Structural Molecular Biology Program is supported by the DOE Office of Biological and Environmental Research, and by the National Institutes of Health, National Institute of General Medical Sciences (NIGMS) (P41GM103393). The contents of this publication are solely the responsibility of the authors and do not necessarily represent the official views of NIGMS or NIH. This work was supported by TTU Health Sciences Center; the Wilson Foundation; the Newby Family (G.A.C.); and NIH Grants R01AR063634 (R.B.S.), 1R35GM128906 (M.P.L.), and 1R35GM124979 (B.J.W.). Publisher Copyright: {\textcopyright} 2020 National Academy of Sciences. All rights reserved.",
year = "2020",
month = jul,
day = "14",
doi = "10.1073/pnas.2006887117",
language = "English",
volume = "117",
pages = "16363--16372",
journal = "Proceedings of the National Academy of Sciences of the United States of America",
issn = "0027-8424",
publisher = "Proceedings of the National Academy of Sciences",
number = "28",
}