SINGLE-STRAND CONFORMATION POLYMORPHISM (SSCP) CAN BE EXPLAINED BY SEMISTABLE CONFORMATION DYNAMICS OF SINGLE-STRANDED-DNA

The cause of separation in gel electrophoresis between highly homologo us ss (single-stranded) DNAs as observed in SSCP (single-strand confor mation polymorphism) was pursued, Advancing our previous explanation [ J. Biochem. 99, 663-871 (1986)], the mobility difference of ssDNAs was correlated to differences in their dynamic conformation (not to diffe rences in their most stable structure), focusing on point-substituted sites, The contribution of semistable conformation dynamics was consid ered to be critical, Putative factors which may influence mobility (i. e., length of ssDNAs, location of substituted sites, and types of subs titutions) were experimentally examined and critically discussed, Unde rstanding of these phenomena should yield improvements in various tech niques, such as SSCP, and in evaluation of the solution structures of DNA.