Insects evolved a monomeric histone-fold domain in the CENP-T protein family.

ABSTRACT: The histone-fold domain (HFD) is a conserved protein interaction module that requires stabilization through a handshake interaction with an HFD partner. All HFD proteins known to date form obligate dimers to shield the extensive hydrophobic residues along the HFD. Here, we find that the lepidopteran kinetochore protein CENP-T is soluble as a monomer. We attribute this stability to a structural rearrangement, which leads to the repositioning of the HFD helix α3. This brings a conserved two-helical extension closer to the histone fold, where it takes over the position and function of the CENP-T partner CENP-W. This change has no effect on the DNA-binding ability of the lepidopteran CENP-T. Our analysis suggests that the monomeric HFD originated in the last common ancestor of insects, with a

SUBMITTER: Sankaranarayanan SR 

PROVIDER: S-EPMC12678787 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature