Expression data from Ezh2-null leukemic cells. Mus musculus

The polycomb group (PcG) proteins function in gene silencing through histone modifications. They form chromatin-associated multiprotein complexes, termed polycomb repressive complex (PRC) 1 and PRC2. These two complexes work in a coordinated manner in the maintenance of cellular memories through transcriptional repression of target genes. EZH2 is a catalytic component of PRC2 and trimethylates histone H3 at lysine 27 to transcriptionally repress the target genes. PcG proteins have been characterized as general regulators of stem cells, but recent works also unveiled their critical roles in cancer. Overall design: Purified leukemic cells from BM of recipient mice transplanted with wild-type and Ezh2-/- leukemic cells transformed with MLL-AF9 leukemic fusion gene were subjected to RNA extraction and hybridization on Affymetrix microarrays.