Acetylation and deacetylation of Cdc25A constitutes a novel mechanism for modulating Cdc25A functions with implications for cancer

Abstract

The dual specificity phosphatase Cdc25A is a key regulator of the cell cycle that promotes cell cycle progression by dephosphorylating and activating cyclin-dependent kinases. In response to genotoxicants, Cdc25A undergoes posttranslational modifications which contribute to its proteasome-mediated degradation and consequent cell cycle checkpoint arrest. The most thoroughly studied Cdc25A modification is phosphorylation. We now provide the first evidence that Cdc25A can be acetylated and that it directly interacts with the ARD1 acetyltransferase which acetylates Cdc25A both biochemically and in cultured cells. When acetylated, Cdc25A has an extended half-life. We have also identified the class IV histone deacetylase, HDAC11, as a Cdc25A deacetylase. We further show that DNA damage, such as exposure to methyl methanesulfonate (MMS), etoposide or arsenic, increases Cdc25A acetylation. Importantly, this acetylation modulates Cdc25A phosphatase activity and its function as a cell cycle regulator, and may reflect a cellular response to DNA damage. Since Cdc25A, ARD1, and HDAC11 are frequently dysregulated in multiple types of cancer, our findings may provide insight into a novel mechanism in carcinogenesis.

Angiogenic Factor With G Patch and FHA Domains 1 Is a Novel Regulator of Vascular Injury

“…19 HDAC11 has been implicated in the regulation of immune response 20,21 and carcinogenesis, 22,23 and our data expand the territory of pathophysiological processes HDAC11 can potentially influence. There are, however, several outstanding issues on the current model.…”

Co-translational, Post-translational, and Non-catalytic Roles of N-Terminal Acetyltransferases

“…Nε acetylation of the cell cycle regulator Cdc25A by NAA10 increases its stability, and this happens as a response to genotoxic stress. This acetylation, which can be reversed by HDAC11, has been suggested to allow time for DNA repair after DNA damage (Lozada et al, 2016). NAA10 is also able to promote autophagosome nucleation through Nε acetylation of phosphoglycerate kinase 1 (PGK1) ( Figure 5C).…”

Critical review of non‐histone human substrates of metal‐dependent lysine deacetylases

“…Most of the cell studies were performed to understand the function of a particular protein of interest. Excluding studies that link functional changes to KDAC activity on histones (and therefore exert a functional effect via gene regulation rather than a change in target acetylation status), these studies rely on one or more tools to manipulate either the level of KDAC expression or activity in the cell, and then measure the change in acetylation of the target protein, usually by immunoblotting using an acetylation specific antibody 31‐82 . (Note that we have only included studies that utilized human cells.…”

“…Other in vitro studies have utilized full‐length proteins that have been purified from cells 51,72,73,98‐100 . This experimental approach is fairly convincing; however, immunoprecipitation from cells often results in the purification of not only the target protein, but also other interacting proteins.…”

“…Therefore, KDACs 2, 7, 9, 10, and 11 collectively only have a few substrate leads demonstrated by single research groups. For most substrate leads, specific sites of acetylation have been determined; however, in a significant number of cases the deacetylation site was not determined, because the change in acetylation level was detected by immunoblotting the candidate substrate protein with a non‐specific anti‐acetyl‐lysine antibody 32,34,36,43,49‐51,54,65‐74 . For a subset of these studies, an acetylated lysine residue in the target protein was identified, but the experiments showing deacetylation could not confirm activity at a particular site.…”