Abstract

BackgroundColorectal cancer (CRC) represents the third most prevalent malignancy globally and ranks as the second leading contributor to cancer-related mortality. Lysine crotonylation, a novel post-translational modification, regulates chromatin dynamics through its dual substrate specificity targeting both histones and non-histone proteins.MethodsWe quantitatively compared crotonylation levels between colorectal tumor specimens and paired adjacent normal tissues. The function and mechanism of specific crotonylation sites in hypercrotonylated proteins were further explored both in vitro and in vivo by introducing mutations that mimic decrotonylation at the crotonylation sites of CDK1.ResultsQuantitative analysis revealed a significant elevation of global crotonylation in colorectal tumor specimens compared to adjacent normal tissues. Through LC-MS/MS analysis, we identified the CDK1 9th lysine crotonylated, and that decrotonylated of CDK1-K9 inhibited colorectal tumor proliferation and migration in vitro and in vivo by arresting the cell cycle at the G2/M phase and inducing apoptosis. Mechanistically, histone acetyltransferase hMOF (KAT8) and histone deacetylase HDAC1 co-mediated CDK1 K9 crotonylation, and the decrotonylated mutation was observed to decrease the interaction of CDK1 with cyclin and kinase activity. Moreover, CDK1 K9 decrotonylation and CDK1 inhibitor RO-3306 exert synergistic effects.ConclusionWe revealed the role of non-histone protein crotonylation in regulating the proliferation and migration of colorectal tumor. Crotonylation inhibited cell proliferation through the crotonylated CDK1 K9 by arresting the cell cycle and inducing apoptosis, and exerts a synergistic effect with the RO-3306 inhibitor.