Structural Basis for pH-mediated Regulation of F-actin Severing by Gelsolin Domain 1.

ABSTRACT: Six-domain gelsolin regulates actin structural dynamics through its abilities to sever, cap and uncap F-actin. These activities are modulated by various cellular parameters like Ca²⁺ and pH. Until now, only the molecular activation mechanism of gelsolin by Ca²⁺ has been understood relatively well. The fragment comprising the first domain and six residues from the linker region into the second domain has been shown to be similar to the full-length protein in F-actin severing activity in the absence of Ca²⁺ at pH 5. To understand how this gelsolin fragment is activated for F-actin severing by lowering pH, we solved its NMR structures at both pH 7.3 and 5 in the absence of Ca²⁺ and measured the pKa values of acidic amino acid residues and histidine

SUBMITTER: Fan JS 

PROVIDER: S-EPMC5368644 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature