ANALYTICAL ULTRACENTRIFUGATION AND AGAROSE-GEL ELECTROPHORESIS AS TOOLS FOR STUDYING CHROMATIN FOLDING IN SOLUTION

Analytical ultracentrifugation and agarose gel electrophoresis each ca n be used to accurately quantify changes in structure that accompany c hromatin folding in solution. Analytical ultracentrifugation directly measures the extent of compaction of each species present in a chromat in sample under a wide range of solution conditions. Agarose gel elect rophoresis yields information about changes in the average surface cha rge density, size and/or shape, and conformational flexibility during chromatin folding. When used together, these methodologies are particu larly powerful. Protocols for the characterization of chromatin foldin g by analytical ultracentrifugation and agarose gel electrophoresis ar e described. Discussion focuses on analysis and interpretation of expe rimental chromatin folding data. (C) 1997 Academic Press.