|
|||||
|
|
Evolutionarily Conserved Proline Residues Impede the Misfolding of the Mouse Prion Protein by Destabilizing an Aggregation-competent Partially Unfolded Form |
|
| Institution: | 1. Indian Institute of Science Education and Research, Pune, India;2. National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bengaluru, India;1. Single Molecule Biophysics Lab, Chemical Sciences Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700064, India;2. Homi Bhaba National Institute, Mumbai, India;1. Department of Biochemistry and Molecular Biology, The University of Kansas Medical Center, Kansas City, KS 66160, United States;2. Eye Research Institute, Oakland University, Rochester, MI 48309, United States;3. Department of Chemistry, Lehigh University, Bethlehem, PA 18015, United States;1. Lab No. 606, Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India;2. Biophysical Chemistry & Structural Biology Laboratory, UM-DAE Centre for Excellence in Basic Sciences, University of Mumbai, Vidyanagari Campus, Mumbai 400098, India;1. The Center for Biomolecular Therapeutics (CBT), Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA;2. Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA;3. Biophysics Graduate Program, University of Maryland, College Park, MD 20742, USA;4. Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA;5. Department of Physics, Arizona State University, Tempe, AZ 85287, USA;6. The Institute of Bioscience and Biotechnology Research (IBBR), Rockville, MD 20850, USA |
| Abstract: | The misfolding of the prion protein has been linked to several neurodegenerative diseases. Despite extensive studies, the mechanism of the misfolding process remains poorly understood. The present study structurally delineates the role of the conserved proline residues present in the structured C-terminal domain of the mouse prion protein (moPrP) in the misfolding process. It is shown that mutation of these Pro residues to Ala leads to destabilization of the native (N) state, and also to rapid misfolding. Using hydrogen–deuterium exchange (HDX) studies coupled with mass spectrometry (MS), it has been shown that the N state of moPrP is in rapid equilibrium with a partially unfolded form (PUF2*) at pH 4. It has been shown that the Pro to Ala mutations make PUF2* energetically more accessible from the N state by stabilizing it relative to the unfolded (U) state. The apparent rate constant of misfolding is found to be linearly proportional to the extent to which PUF2* is populated in equilibrium with the N state, strongly indicating that misfolding commences from PUF2*. It has also been shown that the Pro residues restrict the boundary of the structural core of the misfolded oligomers. Overall, this study highlights how the conserved proline residues control misfolding of the prion protein by modulating the stability of the partially unfolded form from which misfolding commences. |
| Keywords: | prion misfolding partially unfolded form proline hydrogen-deuterium exchange mass-spectrometry moPrP"} {"#name":"keyword" "$":{"id":"k0035"} "$$":[{"#name":"text" "_":"mouse prion wt"} {"#name":"keyword" "$":{"id":"k0045"} "$$":[{"#name":"text" "_":"wild type PUF"} {"#name":"keyword" "$":{"id":"k0055"} "$$":[{"#name":"text" "_":"partially unfolded form CTD"} {"#name":"keyword" "$":{"id":"k0065"} "$$":[{"#name":"text" "_":"C-terminal domain HDX-MS"} {"#name":"keyword" "$":{"id":"k0075"} "$$":[{"#name":"text" "_":"hydrogen-deuterium exchange coupled with mass-spectrometry CD"} {"#name":"keyword" "$":{"id":"k0085"} "$$":[{"#name":"text" "_":"circular dichroism |
| 本文献已被 ScienceDirect 等数据库收录！ | |