Figure 4.

Activation of replication induces a specific alteration of the chromatin structure at the chromosomal ARS1 replication origin. Indirect end-labeling was used to analyze the micrococcal nuclease digestion pattern around the ARS1 region. Two different concentrations of micrococcal nuclease were used (open triangles). The radioactive probe is indicated by a vertical bar (left). The approximate positions of the Gal4-binding sites and the four elements of ARS1 are indicated at left. The cutting sites in chromatin were compared to those in deproteinized DNA (naked) from the RL1 strain. The arrows (a–c) indicate the bands whose intensity was most significantly affected by the stimulatory transcription factors Gal4–CTF and Gal4(1–100) + Gal11P.