Chromatin dynamics and histone modifications in the intestinal microbiota-host crosstalk

Background The microbiota in our gut is an important component of normal physiology that has co-evolved with us from the earliest multicellular organisms. It is, therefore, not surprising that there is an intimate crosstalk between the microbial world in the gut and the host. Genome regulation through microbiota-host interactions not only affect the host’s immunity, but also metabolic health and resilience against cancer. Chromatin dynamics of the host epithelium involving histone modifications and other facets of the epigenetic machinery play an important role in this process. Scope of Review In this review we will discuss recent findings relevant to how chromatin dynamics shape the crosstalk between the microbiota and its host, with special focus on the role of histone modifications. Major Conclusions Host-microbiome interactions are important evolutionary drivers and are, thus, expected to be hardwired into and mould the epigenetic machinery in multicellular organisms. Microbial derived short chain fatty acids (SCFA) emerge as a dominant determinant in microbiome-host interaction and the inhibition of histone deacetylases (HDACs) by SCFA is a key mechanism in this process. The discovery of alternative histone acylations, such as crotonylation, in addition to the canonical histone acetylation reveals a new layer of complexity in this crosstalk.