Chromatin structure and analysis of mechanisms of activators and repressors.

Some transcriptional repressors appear to organize chromatin structure as at least part of their mechanism. Some transcriptional activators appear to alter or remodel chromatin structure as at least part of their mechanism. Understanding transcriptional regulation thus requires methods for investigation of the chromatin structure of specific genes in different states of functional activity. This paper reviews chemical and enzymatic approaches to determination of chromatin structure, the methods used for analysis of the results, and criteria for interpretation of the data to infer chromatin structures.