Fine resolution of histones by two-dimensional polyacrylamide gel electrophoresis: developmental implications.

A two-dimensional electrophoresis for fine separation of histones is described in detail. The method is relatively simple and gives very reproducible results. In the first dimension the histones are separated by their charge in acid-urea gels, while in the second dimension the separation is based on both the charge and the differential affinity of histones to Triton in acid-urea-Triton gels. In this electrophoretic system, the linker histones are resolved on the gel diagonal, while the core histones are separated above the diagonal. The electrophoresis is very sensitive to charge effect, and thus it is very well suited to resolving histone-modified forms. The application of the two-dimensional electrophoresis in Xenopus developmental studies is illustrated.