Fig. 5. Physical interaction between Vps1p and Sla1p. (A) Co-immunoprecipitation of Vps1p and Sla1p. Equal amounts of protein extracts prepared from W303 containing GAL1-myc-VPS1 (lanes 3, 6 and 7), HA-SLA1 (pTHY1108, lanes 1, 4 and 9), or both (lanes 2 and 8), were subjected to anti-HA or anti-Myc immunoprecipitation (IP) and followed by SDS-PAGE and immunoblotting (IB). Vps1-Myc was present in the immunoprecipitates of HA-Sla1p from the co-transformants (lane 5). (B) The physical association between the mutated Vps1p and Sla1p. Strains expressing Vps1p or vps1 GTPase mutants (YMC 458-461) were transformed with HA-SLA1 (pTHY1108) and the vector (pRS314), respectively. Equal amounts of protein extracts prepared from the above strains were subjected to anti-HA or anti-Myc immunoprecipitation (IP) and followed by SDS-PAGE and immunoblotting using anti-Myc antibody.