Remodeling plans for cellular specialization: unique styles for every room

Chromatin-remodeling complexes are biochemically diverse, functionally selective machines that regulate crucial aspects of DNA metabolism, including transcription and chromatin assembly. These complexes modulate histone–DNA interactions to affect nucleosome repositioning and disassembly, and histone variant exchange, thereby generating compositionally specialized chromatin. Recent studies have revealed precise mechanisms by which specific remodelers control the transition from proliferating progenitors to committed cells through a highly synchronized switch in transcriptional programs. This involves temporal and, often, signal-dependent gene-targeted interactions between individual remodelers and tissue-specific master proteins that regulate myogenesis, neurogenesis and lymphogenesis. Distinct remodelers have also been shown to direct self-renewal of different types of stem cells in response to particular microenvironments.