Figure 2. ORCA Exists in Multiple Subcomplexes in the Cell.
(A) Glycerol gradient sedimentation analysis of ORCA complex on material immunoprecipitated with ORCA antibodies. The corresponding molecular weight markers are labeled. Note that ORCA, Orc2, and Orc3 cosediment in fractions 12–14.
(B) Association of ORCA with ORC in human cells. HeLa nuclear extract fractionated over a Superdex 200 gel filtration column and fractions analyzed for ORCA and various ORC subunits by immunoblot. Molecular weight markers are labeled on top of the panel. Note the multiple peaks of ORCA corroborating its existence in multiple subcomplexes.