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MED26 regulates H3K4Me3 by recruiting the COMPASS complex

ABSTRACT: In the nucleus of cells, the regulation of gene expression is a sophisticated and finely tuned process, in which histone modifications play a crucial role. One such modification, H3K4me3 (the trimethylation of lysine 4 on histone H3), is associated with active transcription and typically occurs at promoter regions to facilitate gene expression. Recent studies have illuminated the mechanism by which MED26, a component of the Mediator complex, regulates H3K4me3 levels through the recruitment of the COMPASS (Complex Proteins Associated with Set1) complex.The COMPASS complex is responsible for catalyzing the methylation of histone H3 at lysine 4, an essential step in the activation of gene transcription. MED26 acts as a bridge between the Mediator complex, which is involved in the assembly of transcriptional machinery at gene promoters, and the COMPASS complex. By facilitating this interaction, MED26 ensures that the COMPASS complex is correctly positioned to modify histones, thereby influencing the chromatin structure and accessibility of genes for transcription. This regulatory mechanism underscores the importance of MED26 in coordinating the activities of different protein complexes during gene expression, contributing to cellular functions and development. Understanding the precise role of MED26 in this context provides valuable insights into the molecular mechanisms underlying gene regulation and may have implications for the treatment of diseases associated with aberrant gene expression.

ORGANISM(S): Homo sapiens

PROVIDER: GSE282807 | GEO | 2025/11/25

REPOSITORIES: GEO

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