Copyright information:Taken from "The SUVR4 protein is a nucleolar histone methyltransferase with preference for monomethylated H3K9"Nucleic Acids Research 2006;34(19):5461-5470.Published online 04 Oct 2006PMCID:PMC1636477.© 2006 The Author(s) () RT–PCR analysis of transcript levels in wild-type tissues as indicated, using gene specific primers. Two parallels are shown for each tissue. Actin was used as a positive control and -RT is a negative control without Reverse Transcriptase. () Schematic presentation of splice variants. Grey boxes, exons; black boxes, alternatively spliced exons; lines, introns. Positions of start and stop codons are indicated. () Domain architecture of SUVR1, SUVR2 and SUVR4 proteins. The amino acid sequence of the C-terminal part of SUVR4's SET domain is given. Motifs shown in other SET-domain proteins to be important for HMTase activity (27) are underlined, and a residue of importance for product specificity (28) is indicated by an arrowhead. The arrow indicates the start of the SUVR1b splice variant. Boxes in black, NLS; white, pre-SET and post-SET domains; light grey, SUVR-specific pre-SET region; dark grey, SET domain; gray gradient, WIYLD domain.