HDAC7 is a repressor of myeloid genes whose downregulation in pre-B cells is required for transdifferentiation into macrophages

In the immune system HDAC7 is expressed in T cells where it regulates the expression of key genes for T cell development and function. Here we report that HDAC7 is also highly expressed in B cell precursors, where it is recruited by MEF2C to repress the activity of key genes for myeloid cell function. While HDAC7 is down-regulated during the conversion of pre-B cells into macrophages, re-expression of HDAC7 interferes with both the acquisition of the myeloid gene transcriptional program and macrophage specific cell functions. Thus, HDAC7 is a novel transcriptional repressor of lineage inappropriate genes in B cells. Biological duplicates of C10-MSCV and C10-HDAC7 cells were un-iduced or induced to transdifferentiate for 48 and 72 hors. Total RNA from cultured cells was extracted by Trizol and then purified. PCR amplified RNAs were hybridized against Affymetrix mouse arrays chip (Mouse Genome 430 PM strip).