Pseudo-acetylation of ACTC1 K326 and K328 promotes dysinhibition of reconstituted human cardiac thin filaments

ABSTRACT: Tropomyosin (Tpm) regulates cardiac thin filament function by restricting myosin access through electrostatic interactions with actin - particularly involving residues K326 and K328 on each actin monomer. Acetylation at these lysines neutralizes charge, destabilizing Tpm’s inhibitory position and favoring myosin engagement. We hypothesize that mimicking this modification via a K to Q mutation would enhance contractility due to Tpm’s disinhibition. To determine whether cardiac actin amino acids K326 and 328 are acetylated in human cardiac tissue, we performed in-gel tryptic digestion of the major 42 kDa SDS-PAGE band (actin) from non-failing, donor cardiac homogenate replicates, and subsequently subjected the peptides to LC-MS/MS.

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Heart

SUBMITTER: Sogol Sedighi  

LAB HEAD: Anthony Cammarato

PROVIDER: PXD067808 | Pride | 2026-08-31

REPOSITORIES: Pride