# Histone 3 lysine 36 trimethylation by SETD2 shapes an epigenetic landscape in intestinal stem cells to orchestrate lipid metabolism and attenuate cell senescence

## TL;DR

This study shows how a specific epigenetic modification helps intestinal stem cells manage lipid metabolism and delay aging.

## Contribution

The study reveals a novel role for H3K36me3 in connecting lipid metabolism and stem cell aging.

## Key findings

- H3K36me3 deficiency reduces stem cell proliferation and disrupts fatty acid oxidation.
- Loss of H3K36me3 increases chromatin accessibility and alters gene expression related to senescence.
- Metabolic intervention can prevent stem cell senescence caused by H3K36me3 deficiency.

## Abstract

The self-renewal capacity of intestinal stem cells (ISCs) declines with aging, leading to a loss of homeostasis and an increased susceptibility to intestinal diseases. Despite the established significance of lipid metabolism and epigenetic regulation in ISC function, the molecular mechanisms that connect these processes to aging-related ISC dysfunction remain elusive. Here, we hypothesize that histone 3 lysine 36 trimethylation (H3K36me3) might act as a bridge between these processes. In this study, we demonstrate that H3K36me3 caused by SETD2 is critical for ISC stemness. H3K36me3 deficiency results in reduced ISC proliferation and differentiation, disrupts fatty acid oxidation (FAO), and promotes ISC senescence. Mechanistically, the loss of H3K36me3 triggers the activity of the SWI/SNF chromatin remodeling complex and leads to increased chromatin accessibility and enhancer activation, which alters FAO- and senescence-related gene expression. Importantly, our data demonstrate that metabolic intervention can prevent the senescence of ISC due to H3K36me3 deficiency. Our findings reveal a crucial role for H3K36me3 in maintaining the epigenetic landscape that orchestrates FAO and determines intestinal stem cell functions, emphasizing the role of FAO as a key modulator between H3K36me3 and ISC aging, suggesting that metabolic intervention may help mitigate age-related ISC dysfunction.