Fig. 4.
FAC protein is located in the cytoplasm and nucleus of normal and FA EBV-transformed human lymphoblasts. Cells were fractionated according to the method of Tsuda et al,27 and the separated nuclear and cytoplasmic lysates were analyzed by SDS-PAGE. FAC protein was detected by probing transferred proteins with FAN2 antisera. The blot was stripped and reprobed with anti-β tubulin as a control for artifactual presence of cytoplasmic protein in nuclear fractions as described in Fig 3. Reprobing with anti-FAC1 gave similar results (data not shown). Lane 1, JY cytoplasmic fraction; lane 2, HSC536N cytoplasmic fraction; lane 3, JY nuclear fraction; lane 4, HSC536N nuclear fraction. The cytoplasmic fractions (70 μg total protein loaded) contain approximately one fourth the cell number of the nuclear fractions (50 μg total protein loaded).