The DOT1 domain regulates gene expression by methylating histone H3 [1]. H3 methylation by DOT1 has been shown to be required for the DNA damage checkpoint in yeast [2].
Sawada K, Yang Z, Horton JR, Collins RE, Zhang X, Cheng X.
Structure of the conserved core of the yeast Dot1p, a nucleosomal histone H3 lysine 79 methyltransferase.
J. Biol. Chem. 279 43296-306 2004
[PubMed: 15292170] http://dx.doi.org/10.1074/jbc.M405902200
2.
Giannattasio M, Lazzaro F, Plevani P, Muzi-Falconi M.
The DNA damage checkpoint response requires histone H2B ubiquitination by Rad6-Bre1 and H3 methylation by Dot1.
J. Biol. Chem. 280 9879-86 2005
[PubMed: 15632126] http://dx.doi.org/10.1074/jbc.M414453200