Figure 1. Expression levels of loss-of-function BRCA1 mutants.
Cell lysates containing comparable cell numbers were separated on SDS-PAGE. At least two independent transformants were assayed for each mutant to control for clonal variation. LexA fusion mutant proteins expressed in yeast were detected by western blot using a monoclonal α-LexA antibody. A schematic representation of the fusion proteins bearing missense mutations (white arrow; M.W. 65 kDa) and a nonsense mutation (gray arrow; M.W. 49 kDa) is shown. Note that mutation Y1769X disrupts the BRCT-C but retains BRCT-N.