Expanding the HP1a-binding consensus and molecular grammar for heterochromatin assembly.

ABSTRACT: The recruitment of Heterochromatin Protein 1 (HP1) partners is essential for heterochromatin assembly and function, yet our knowledge regarding their organization in heterochromatin remains limited. Here, we show that interactors engage the DrosophilaHP1 (HP1a) dimer through a degenerate and expanded form of the previously identified PxVxL motif, which we now term HP1a Access Codes (HACs). These HACs reside in disordered regions, possess high conservation among Drosophilahomologs, and contain alternating hydrophobic residues nested in a cluster of positively charged amino acids. These findings and molecular dynamics simulations identify key electrostatic interactions that modulate HP1a-binding strength and provide a dramatically improved HP1a-binding consensus motif that can reveal protein

SUBMITTER: Colmenares SU 

PROVIDER: S-EPMC12526061 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature