Figure 2.

(A) Nucleotide sequence of the double-stranded 34-bp fragment used as a substrate for modification. The possible sites of intra- and interstrand cross-linking by either cis-DDP or trans-DDP are marked on the sequence. (B) Electrophoretic analysis of the binding of increasing amounts of histone H1 to trans-modified, cis-modified, or unmodified 34-bp fragments. Lanes C contain the respective DNA controls without H1; the successive lanes contain increasing amounts of histone H1 (expressed as one molecule of H1 per number of bp) as follows: 1/64, 1/32, 1/16, and 1/10. Lane M contains pUC19/HinfI marker.