Three main epigenetic mechanisms cooperate to regulate the state of the chromatin (Bernstein et al., 2007; Hargreaves and Crabtree, 2011): DNA methylation on the cytosine residues of CpG dinucleotides; covalent modifications of histone tails; and ATP-dependent chromatin remodeling which utilizes the energy of ATP hydrolysis to move or exchange nucleosomes. In this review, we focus on a family of multimeric ATP-dependent chromatin remodeling complexes called BAF (BRG1/BRM-associated factors), also known as mammalian SWI/SNF (mSWI/SNF) for their limited similarity to the yeast SWI/SNF complex. BAF complexes have emerged at the forefront of human neurological diseases following recent discoveries which implicate BAF subunit mutations in syndromic and non-syndromic intellectual disability (Santen et al., 2013, 2012; Tsurusaki et al., 2013, 2012; Hoyer et al., 2012; Halgren et al., 2012; Van Houdt et al., 2012; Backx et al., 2011; Wieczorek et al., 2013), sporadic autism (Neale et al., 2012; O’Roak et al., 2012), schizophrenia (Loe-Mie et al., 2010; Koga et al., 2009) and amyotrophic lateral sclerosis (Chesi et al., 2013). These important findings from human genetics indicate that BAF complexes make rate-limiting contributions to the establishment of the diversity, stability and plasticity found in our nervous system.
