SET domain

A SET domain is a specific protein structure that occurs in various proteins and plays an important role in the regulation of gene expression and the modification of histones (Herz HM et al. 2013).

Structure: The SET domain is typically about 130 to 150 amino acids long and has a characteristic fold that enables catalytic activity.

Function: SET domains are mainly known as methyltransferases that transfer methyl groups to specific lysine residues in histone proteins. This modification is an important mechanism of epigenetic regulation that influences the accessibility of DNA to transcription factors and thus regulates gene expression.

Biological significance:

• Epigenetics: Methylation of histones by SET domains influences chromatin structure and gene activity. For example, methylation of histone H3 at lysine 4 (H3K4) may be associated with active gene expression, while methylation at lysine 27 (H3K27) is often associated with gene repression.

Development and differentiation: SET domains are important in embryonic development and cell differentiation as they regulate gene expression in different cell types.

Related protein families (SET domain proteins): There are many proteins that contain a SET domain, including important histone methyltransferases such as SET1, SET2, EZH2 (part of the PRC2 complex) and many others. These proteins are crucial for the epigenetic control of gene expression and may also be involved in the regulation of other cellular processes (Luo H et al. 2023).

1. Herz HM et al. (2013) SET for life: biochemical activities and biological functions of SET domain-containing proteins. Trends Biochem Sci 38:621-639.

2. Luo H et al. (2023) The functions of SET domain bifurcated histone lysine methyltransferase 1 (SETDB1) in biological process and disease. Epigenetics Chromatin 16:47.