Structural Impact of Phosphorylation and Dielectric Constant Variation on Synaptotagmin's IDR.

ABSTRACT: We used time-resolved Förster resonance energy transfer, circular dichroism, and molecular dynamics simulation to investigate the structural dependence of synaptotagmin 1's intrinsically disordered region (IDR) on phosphorylation and dielectric constant. We found that a peptide corresponding to the full-length IDR sequence, a ∼60-residue strong polyampholyte, can sample structurally collapsed states in aqueous solution, consistent with its κ-predicted behavior, where κ is a sequence-dependent parameter that is used to predict IDR compaction. In implicit solvent simulations of this same sequence, lowering the dielectric constant to more closely mimic the environment near a lipid bilayer surface promoted further sampling of collapsed structures. We then examined the structural tendencies of

SUBMITTER: Fealey ME 

PROVIDER: S-EPMC5985037 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature