Project description:In C. albicans the sirtuin Hst3p is responsible for removing the acetyl group of the Lys 56 of the H3 histone which is particularly abundant in yeasts and contributes to fungal genome integrity and virulence. Here we identified the H3K56ac patterns across Candida albicans genome in cells maintained for 28 h in YPD at 25°C in the presence or absence of 10 mM nicotinamide (used in this study as Hst3p inhibitor). Chromatin immunoprecipitation was carried out using an anti-H3K56ac antibody, whereas input samples were taken before addition the antibody. Two biological replicates were performed for each condition.
Project description:We use high-throughput sequencing to profile the response of the opportunistic fungal pathogen Candida albicans to mucins from the mucosal niche. We find that C. albicans undergoes a genome-wide phenotypic shift in response to mucins suppressing virulence-associated pathways.
Project description:In the present study, we investigated whether the acetylation of H3K56, known as relevant for C. albicans virulence, might affect the Candida-macrophages interaction. Therefore, by the mean of the non-specific Hst3 inhibitor nicotinamide (NAM), we evaluated whether the alteration of H3K56 acetylation would affect the secretion of soluble factors by C. albicans. In particular, we tested the effect of the two different Candida growth-conditioned media (with and without NAM) on murine macrophages at the morphological and functional levels. In addition, we analyzed transcriptome modifications and genome enrichment of H3K56ac in the same experimental conditions.
Project description:We use high-throughput sequencing to profile the response of the opportunistic fungal pathogen Candida albicans to mucins and mucin-glycans from the mucosal niche. We find that C. albicans undergoes a genome-wide phenotypic shift in response to mucins and their attached glycans suppressing virulence-associated pathways.
Project description:Sirt6, the NAD+-dependent deacetylase, has been described to deacetylate H3K9, H3K18, and H3K56. However, analysis of the acetylation status revealed that loss of Sirt6 caused a massive increase of histone H3K56ac levels but no detectable change of histone H3K9ac and H3K18ac, indicating that SIRT6 is the dominant deacetylase for H3K56ac in muscle stem cells (MuSCs). Further, we investigate genome-wide H3K56ac profiling in the absence of Sirt6 in MuSCs and mouse embryonic stem cells (mESCs) using high throughput sequencing (ChIP-seq).
Project description:Sirt6, the NAD+-dependent deacetylase, has been described to deacetylate H3K9, H3K18, and H3K56. However, analysis of the acetylation status revealed that loss of Sirt6 caused a massive increase of histone H3K56ac levels but no detectable change of histone H3K9ac and H3K18ac, indicating that SIRT6 is the dominant deacetylase for H3K56ac in muscle stem cells (MuSCs). Further, we investigate genome-wide H3K56ac profiling in the absence of Sirt6 in MuSCs and mouse embryonic stem cells (mESCs) using high throughput sequencing (ChIP-seq).
Project description:Candida spp. represent the third most frequent worldwide cause of infection in Intensive Care Units (ICUs) with a mortality rate of almost 40%. The classes of antifungals currently available include azoles, polyenes, echinocandins, pyrimidine derivatives, and allylamines. However, the therapeutical options for the treatment of candidiasis are drastically reduced by the increasing antifungal resistance. The growing need of a more targeted antifungal therapy is limited by the concern of finding molecules that specifically recognize the microbial cell without damaging the host. Epigenetic writers and erasers have emerged as promising targets in different contexts, including the treatment of fungal infections. In C. albicans, Hst3p, a sirtuin that deacetylates histone H3K56ac, represents an attractive antifungal target as it is essential for the fungus viability and virulence. Although the relevance of such epigenetic regulator is documented for the development of new antifungal therapies, the molecular mechanism behind Hst3p-mediated epigenetic regulation remains unrevealed. Here, we provide the first genome-wide profiling of H3K56ac in C. albicans; H3K56ac enriched regions are associated with Candida sp. pathogenicity. Upon Hst3p inhibition, 447 regions gain H3K56ac. Importantly, these genomic areas contain genes encoding for adhesin proteins, degradative enzymes, and white-opaque switch. Moreover, our RNA-seq analysis revealed 1330 upregulated and 1081 downregulated transcripts upon Hst3p inhibition, and among them, 87 genes whose transcription upregulation correlates well with changes in promoter H3K56 acetylation, including some well-known regulators of phenotypic switching and virulence, confirming that Hst3p is an appealing target for the development of new potential antifungal target.
Project description:In the present study, we investigated whether the acetylation of H3K56, known as relevant for C. albicans virulence, might affect the Candida-macrophages interaction. Therefore, by the mean of the non-specific Hst3 inhibitor nicotinamide (NAM), we evaluated whether the alteration of H3K56 acetylation would affect the secretion of soluble factors by C. albicans. In particular, we tested the effect of the two different Candida growth-conditioned media (with and without NAM) on murine macrophages at the morphological and functional levels. In addition, we analyzed transcriptome modifications and genome enrichment of H3K56ac in the same experimental conditions.
Project description:Candida albicans is a ubiquitous opportunistic pathogen that is the most prevalent cause of hospital-acquired fungal infections. In mammalian hosts, C. albicans is engulfed by phagocytes that attack the pathogen with DNA-damaging reactive oxygen species (ROS). Acetylation of histone H3 lysine 56 (H3K56) by the fungal-specific histone acetyltransferase Rtt109 is important for yeast model organisms to survive DNA damage and maintain genome integrity. To assess the importance of Rtt109 for C. albicans pathogenicity, we deleted the predicted homologue of Rtt109 in the clinical C. albicans isolate, SC5314. C. albicans rtt109 -/- mutant cells lack acetylated H3K56 (H3K56ac) and are hypersensitive to genotoxic agents. Additionally, rtt109 -/- mutant cells constitutively display increased H2A S129 phosphorylation and elevated DNA repair gene expression, consistent with endogenous DNA damage.