SMARCA2
BRM
BRM and BRG1 are ATPase core subunits of the mammalian SWI/SNF complex. The two proteins are 75% similar in protein composition, are mutually exclusive in chromatin remodeling complexes in vitro, and appear to have tumor-suppressor functions.
As BRM was originally identified in Drosophila as a suppressor of Polycomb, it is tempting to speculate that loss of BRM or BRG1 impinge on cellular homeostasis by affecting the balance between TrxG and PcG protein complexes.
Mouse model
Brm-/- mice do not appear tumor prone. The mice are larger than wild type, and isolated mutant fibroblast cells display G0/G1 checkpoint failure on DNA damage, indicating a role for BRM in cell cycle regulatio).