H3K36me

Histone modification

Overview

H3K36me refers to the methylation of the 36th lysine residue on the histone H3 protein. This post-translational modification is a key epigenetic marker involved in the regulation of gene expression, DNA repair, and chromatin structure. Methylation at this site can occur in three forms: monomethylation (H3K36me1), dimethylation (H3K36me2), and trimethylation (H3K36me3), each having distinct biological functions.

Function

H3K36 methylation plays a crucial role in transcriptional regulation. H3K36me3 is predominantly associated with actively transcribed genes and is enriched in the bodies of these genes. It is thought to facilitate the transition of RNA polymerase II from initiation to elongation during transcription. Additionally, H3K36me2 is involved in the repression of cryptic transcription initiation within gene bodies, thereby maintaining transcriptional fidelity.

Methylation of lysine

Biological Significance

The methylation of H3K36 is catalyzed by specific histone methyltransferases, such as SETD2, which is responsible for the trimethylation of H3K36. This modification is recognized by various "reader" proteins that contain chromodomains, PWWP domains, or Tudor domains, which mediate downstream effects on chromatin structure and function.

H3K36me3 is also implicated in DNA repair processes, particularly in the context of homologous recombination. It is thought to recruit repair factors to sites of DNA damage, thereby facilitating the repair process.

Role in Disease

Alterations in H3K36 methylation patterns have been linked to various diseases, including cancer. Mutations in the SETD2 gene, which lead to aberrant H3K36 methylation, have been observed in several types of cancer, such as renal cell carcinoma and glioma. These mutations can disrupt normal gene expression and contribute to tumorigenesis.

Related pages

• Histone modification
• Epigenetics
• Chromatin
• Gene expression
• DNA repair