In C. albicans, after yeast-macrophage interaction up to 30% of yeast cells suffers oxidative stress mediated-apoptosis. In previous studies to reveal the response mechanisms to oxidative stress of this yeast we performed a quantitative proteomic analysis in cells exposed to hydrogen peroxide to evaluate changes in their proteome. In the analysis we identified a high increase in different oxidoreductase proteins like Oye32 but also in new undescribed proteins like Prn1, a protein similar to pirins. Pirins has already been described as a nuclear redox sensor in mammal cells which are implicated in oxidative stress response and as coregulator of different the transcription factors implicated in proliferation. Therefore, is probably that C. albicans Prn1 function will be related with oxidative stress response and also working as a regulator of different protein expression in response to this stress. In addition, prn1 lacks a homologue in S. cerevisiae, suggesting that it may be specific to pathogenic fungi, which makes important to study the role of this protein in the cell to finally be considered a possible drug target. In order to uncover the possible function of Prn1 in response to oxidative stress in C. albicans we carried out a quantitative proteomic assay in a wild type (SN250) and a prn1 strain treated with hydrogen peroxide. The main objective of the experiment was to identify which proteins decrease its abundance in prn1 cells in comparation with wild type cells in response to oxidative stress which means that their expression could be coregulated by Prn1. The second objective was to identify which proteins are overexpressed in response to oxidative stress to supply the lack or Prn1 which is very useful to identify new proteins implicated in oxidative stress response. Finally, these deceased and overexpressed proteins allowed us to identify which signalling pathways are regulated directly by Prn1 in response to oxidative stress.