Figure 1. Limited proteolysis of purified BRCA1-(230–534).

Proteolysis was conducted at room temperature over a 60 min period, with trypsin/protein ratios of (a) 1:500 and (b) 1:1000. The digestion products were analysed by SDS/15% PAGE by comparison with molecular-mass standards (lanes 1; sizes are indicated in kDa). Lanes 2–9 are 0, 5, 10, 15, 20, 30, 40 and 60 min digests respectively. The fragments were visualized by Coomassie Blue staining, and the arrow indicates the stable domain.