The role of histone crotonylation in intestinal stem cells

Abstract

The regulation of the proliferation and differentiation of intestinal stem cells (SSIs) is crucial for intestinal homeostasis. These processes are, in part, regulated by microbiota signals, especially short-chain fatty acids (AGCCs), which induce Post-Translational Modifications (PTMs) including histone acetylation and crotonylation, which are important in the regulation of gene expression. In this study we will analyze the acylation pattern (acetylation and crotonylation) of histones from colonic SSIs in a physiological context. In addition, we will investigate the relevance of these PTMs for gene expression and ISC functions. For this purpose, we will evaluate the acylation of histones from the colonic ISCs of C57/BL6 animals kept in conditions that alter the microbiota and the endogenous production of AGCCs, including diets with or without fibers, and treatment or not with antibiotics. We will detect and quantify the PTMs in these conditions through flow cytometry, Western Blot and immunofluorescence (IF). We will analyze the impact of acylations on ISC gene expression through RNA-seq and ChIP-qPCR. We will study the functional impact of PTMs on ISCs by comparing their proliferation by EdU, IF acylations and their differentiation capacity in the different cell types that compose the intestinal epithelium. These analyzes will be complemented with the use of organoids derived from the colon of control animals, incubated or not with inducers of crotonylation and acetylation. With this project, we intend to advance the knowledge about the regulation of ISCs by the microbiota, which is relevant not only in homeostasis, but also for tissue regeneration after damage and in the development of intestinal Cancer. (AU)