Human recombinant PRDM9 expressed in Sf9 insect cells with an N-terminal GST-tag. Catalyzes the transfer of methyl groups from S-adenosyl-L-methionine (SAM) to the epsilon-amino function of protein L-lysine residues, specifically histone H3 lysine-4 (H3K4). Expressed only in meiotic male and female germ cells, PRDM9 is required for fully-functional pairing of homologous chromosomes, double strand break repair, meiotic progression and fertility. PRDM9 binds, via its C-terminal array of zinc fingers (ZnFs), to sequence motifs associated with “hotspots” for homologous recombination (crossovers). Such hotspots are enriched for trimethylated histone H3 lysine-4 (H3K4me3), presumably the result of PRDM9’s H3K4 methyltransferase activity, and part of PRDM9’s role may be to direct meiotic recombination events away from non-PRDM9 H3K4me3 marks, such as those in promoters. PRDM9’s histone methyltransferase activity has received relatively little study, although results with the E. coli-expressed mouse enzyme imply that it is an H3K4 trimethylase that only catalyzes the H3K4me2 to H3K4me3 transition. However, since RBC’s insect cell-expressed human enzyme is most active with, among the substrates tested, the presumably unmethylated E. coli-expressed histone H3.3 (RBC Cat. # HMT-11-134), this would suggest that it is capable of other methylations as well.

SUPPLIED AS: Solution of purified recombinant protein in 50 mM Tris/HCl pH 7.5, 500 mM NaCl, 1 mM TCEP, 10% glycerol (v/v).

STORAGE: -80°C, aliquot and snap-freeze after first use.