FEATURES

FAMILY

DESCRIPTION

Also known as CLR4_SCHPO, clr4, kmt1. Histone methyltransferase which contributes to the establishment of heterochromatin by specifically methylating histone H3 to form H3K9me (PubMed:16024659, PubMed:8138176). Part of the Clr4 methyltransferase complex (ClrC). ClrC preferentially ubiquitylates H3K14 and ClrC-mediated H3 ubiquitination promotes clr4 methyltransferase activity (PubMed:31468675). Clr4 functions as a reader and writer of H3K9 methylation. It sets the H3K9me mark and afterwards this H3K9me mark is recognized by the chromodomains of clr4 and swi6/HP1, which then recruit additional clr4 leading to the methylation of neighboring nucleosomes (PubMed:11242054, PubMed:18345014, PubMed:21224386). H3K9me represents a specific tag for epigenetic transcriptional repression by recruiting swi6/HP1 to methylated histones which leads to transcriptional silencing within centromeric heterochromatin, telomeres, ribosomal DNA repeats, and the silent mating-type region (PubMed:16024659, PubMed:8138176). Clr4 methyltransferase activity promotes the assembly of a tripartite complex composed of ClrC and complexes involved in siRNA generation (PubMed:20705239). Apart from H3K9, methylates also non-histone proteins such as mlo3 (PubMed:21436456, PubMed:28143796). Interacts with mlo3 to promote the processing of centromeric and antisense RNAs (PubMed:21436456). Component of the Clr4 methyltransferase complex (ClrC) composed of at least clr4, rik1, pcu4, rbx1, raf1 and raf2. The cullin pcu4, rik1, raf1, raf2 and the ring-box protein rbx1 are components of an E3 ubiquitin ligase, whose activity is essential for heterochromatin assembly (PubMed:16024659, PubMed:16127433, PubMed:17114925, PubMed:12389037). Interacts directly with pcu4 (PubMed:16127433). Interacts with mlo3 (PubMed:21436456).

EXTERNAL LINKS

clr4

Histone-lysine N-methyltransferase, H3 lysine-9 specific

clr4

Molecular Synopsis