Fig. 1. Holo TFIIIC protects A box, B box and terminator regions of the VA1 gene. DNA fragments containing the full-length (–96 to +232) (lanes 1–6) or the terminator region (+101 to +232) (lanes 7–10) of the VA1 gene were labeled at the lower (lanes 1–3) or the upper (lanes 4–10) strand end with ³²P. The labeled DNA fragments were incubated with mock immunoprecipitate (2 µl) (lanes 2, 5 and 7) or with 100 (2 µl) (lane 9) or 200 (4 µl) (lanes 3, 6 and 10) fmol of immunopurified holo TFIIIC, or 2 µl (0.2 µg protein) of the purified TFIIIC1′ fraction (lane 8). Lanes 1 and 4 are the Maxam–Gilbert G + A reactions. The protected regions are indicated on the left. The hypersensitive site (+88) is indicated by an arrow.