Figure 4.
The 59 kDa protein is specifically UV photo-cross-linked to the A.castellanii 5S RNA gene promoter. (A) A schematic representation of the 5S RNA gene shows the positions of each photoderivative. IE, intermediate element; TIS, transcription initiation site; Tn, termination site. (B) Affinity-purified TFIIIA (+) was cross-linked to 7500 c.p.m. of the indicated photoaffinity probe in a 30 µl reaction. Protein markers are indicated at the left of the panel. NS, reactions preincubated with 8 ng of pBS(–) non-specific competitor DNA; S, reactions preincubated with 8 ng pBS+5S.3 specific competitor DNA; –, reactions lacking TFIIIA or competitor DNA. Labeled peptides are indicated with arrows.