RIZ: RIZ is an Rb-binding protein and also a co-activator of the oestrogen receptor. It contains an N-terminal SET domain and a C-terminal domain that allows RIZ proteins to dimerize. The RIZ SET domain has previously been referred to as a PR-domain. To date, none of the RIZ proteins has been shown to possess methyltransferase activity, probably because of inappropriate assay conditions. (1)

Reference
1. Schneider R, Bannister AJ, Kouzarides T.Unsafe SETs: histone lysine methyltransferases and cancer. Trends Biochem Sci.2002;27(8):396-402. PMID: 12151224.