Premium
Evolution of a protein folding nucleus
Author(s) -
Xia Xue,
Longo Liam M.,
Sutherland Mason A.,
Blaber Michael
Publication year - 2016
Publication title -
protein science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.353
H-Index - 175
eISSN - 1469-896X
pISSN - 0961-8368
DOI - 10.1002/pro.2848
Subject(s) - trefoil , folding (dsp implementation) , nucleus , computational biology , proteome , protein folding , permutation (music) , biophysics , protein structure , biology , physics , genetics , biological system , microbiology and biotechnology , biochemistry , electrical engineering , acoustics , agronomy , engineering
The folding nucleus (FN) is a cryptic element within protein primary structure that enables an efficient folding pathway and is the postulated heritable element in the evolution of protein architecture; however, almost nothing is known regarding how the FN structurally changes as complex protein architecture evolves from simpler peptide motifs. We report characterization of the FN of a designed purely symmetric β‐trefoil protein by ϕ ‐value analysis. We compare the structure and folding properties of key foldable intermediates along the evolutionary trajectory of the β‐trefoil. The results show structural acquisition of the FN during gene fusion events, incorporating novel turn structure created by gene fusion. Furthermore, the FN is adjusted by circular permutation in response to destabilizing functional mutation. FN plasticity by way of circular permutation is made possible by the intrinsic C 3 cyclic symmetry of the β‐trefoil architecture, identifying a possible selective advantage that helps explain the prevalence of cyclic structural symmetry in the proteome.