NMR study of the cataract-linked P23T mutant of human gammaD-crystallin shows minor changes in hydrophobic patches that reflect its retrograde solubility.
The Pro23 to Thr (P23T) mutation in human gammaD-crystallin (HGD) shows several cataract phenotypes. We found earlier [A. Pande, O. Annunziata, N. Asherie, O. Ogun, G.B. Benedek, J. Pande, Decrease in protein solubility and cataract formation caused by the Pro23 to Thr mutation in human gamma D-crystallin, Biochemistry 44 (2005) 2491-2500] that the mutation dramatically lowers the solubility of P23T but the overall protein fold is maintained. Recently we observed that solutions of P23T showed liquid-liquid phase transition behavior similar to that of HGD but the liquid-protein crystal phase transition was altered, suggesting an asymmetric distribution of "sticky" patches on the protein surface [J.J. McManus, A. Lomakin, O. Ogun, A. Pande, M. Basan, J. Pande, G.B. Benedek, Altered phase diagram due to a single point mutation in human gammaD-crystallin, Proc. Natl. Acad. Sci. USA 104 (2007) 16856-16861]. Here we present high-resolution NMR studies of HGD and P23T in which we have made nearly complete backbone assignments. The data provide a structural basis for explaining the retrograde solubility of P23T by (a) identifying possible "sticky" patches on the surface of P23T and (b) highlighting their asymmetric distribution.
Pande
Ajay
A
Department of Chemistry, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY 12222, USA.
Zhang
Jianchao
J
Banerjee
Priya R
PR
Puttamadappa
Shadakshara S
SS
Shekhtman
Alexander
A
Pande
Jayanti
J
D002386:Cataract / Q000235:genetics / Q000378:metabolism*; D003459:Crystallins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D009682:Magnetic Resonance Spectroscopy; D009154:Mutation; D011392:Proline / Q000737:chemistry / Q000235:genetics; D011487:Protein Conformation; D017510:Protein Folding; D012995:Solubility; D013912:Threonine / Q000737:chemistry / Q000235:genetics; D038222:gamma-Crystallins
C504903:CRYGD protein, human; D003459:Crystallins; D038222:gamma-Crystallins; D013912:Threonine; D011392:Proline