Ulp1 Regulates Cell Proliferation Through INO1 in .

Background/objectives: Ulp1 is a vital regulator of the cell cycle, with its absence leading to G2/M phase arrest in . This study aims to investigate the role of Ulp1 in cell cycle regulation in and to elucidate its mechanisms of action, particularly through the modulation of the gene .

Methods: We generated Ulp1 knockout strains in using the FLP-FRT system and performed RNA sequencing (RNA-seq) to analyze gene expression changes. We assessed cell proliferation in knockout and overexpressing strains, as well as the effects of inositol supplementation.

Results: Our findings revealed significant downregulation of and other genes in knockout strains. Importantly, overexpression of restored cell proliferation, indicating that Ulp1 regulates this process via INO1. Notably, supplementation with exogenous inositol did not rescue cell proliferation, suggesting that the enzymatic activity of INO1 is not required for Ulp1's regulatory function.

Conclusions: This study demonstrates that Ulp1 modulates cell proliferation in through INO1, independent of its enzymatic activity. These insights enhance our understanding of Ulp1's role in cell cycle regulation and open new avenues for exploring the molecular mechanisms governing yeast cell division. Further investigations are warranted to delineate the intricate regulatory pathways involved in this process.