Histone H3 lysine 4 mono-methylation does not require ubiquitination of histone H2B.
The yeast Set1-complex catalyzes histone H3 lysine 4 (H3K4) methylation. Using N-terminal Edman sequencing, we determined that 50% of H3K4 is methylated and consists of roughly equal amounts of mono, di and tri-methylated H3K4. We further show that loss of either Paf1 of the Paf1 elongation complex, or ubiquitination of histone H2B, has only a modest effect on bulk histone mono-methylation at H3K4. Despite the fact that Set1 recruitment decreases in paf1delta cells, loss of Paf1 results in an increase of H3K4 mono-methylation at the 5' coding region of active genes, suggesting a Paf1-independent targeting of Set1. In contrast to Paf1 inactivation, deleting RTF1 affects H3K4 mono-methylation at the 3' coding region of active genes and results in a decrease of global H3K4 mono-methylation. Our results indicate that the requirements for mono-methylation are distinct from those for H3K4 di and tri-methylation, and point to differences among members of the Paf1 complex in the regulation of H3K4 methylation.
Dehé
Pierre-Marie
PM
Laboratoire d'Ingénierie des Systèmes Macromoléculaires et Institut de Biologie Structurale et Microbiologie, CNRS, 31 chemin Joseph Aiguier, 13402, Marseille, Cedex 20, France.
Pamblanco
Mercè
M
Luciano
Pierre
P
Lebrun
Régine
R
Moinier
Danièle
D
Sendra
Ramon
R
Verreault
Alain
A
Tordera
Vicente
V
Géli
Vincent
V
D006657:Histones / Q000737:chemistry / Q000378:metabolism*; D008239:Lysine / Q000378:metabolism*; D008745:Methylation; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D025801:Ubiquitin / Q000378:metabolism*
D006657:Histones; D025801:Ubiquitin; D008239:Lysine