(A) (left) Sucrose co-sedimentation binding experiments were performed using either wild type, full-length TRIM5αAGMpyg (Wild Type, lanes 1, 2), or a truncated TRIM5αAGMpyg that lacked the SPRY domain (ΔSPRY, lanes 3, 4), in the absence (lanes 1, 3) or presence of CA tubes (lanes 2, 4). Pelletable CA and associated TRIM5αAGMpyg (Pellet, 30% in total), were separated from unassembled and soluble CA proteins and unbound TRIM5αAGMpyg (Supernatant, 3% of total) by centrifugation through a sucrose cushion, and analyzed by western blotting, with the input levels of both proteins shown for reference (Input, 3% of total). (right) Analogous experiments performed with proteolysis-resistant TRIMCypK283D,Q287D in the absence (lane 5) or presence (lanes 6, 7) of helical CA tubes, without (lanes 5, 6) or with added cyclosporine A (CsA) (lane 7), a competitive inhibitor of the CypA-CA interaction. Lane 8 is a CA tube control, with no added TRIMCypK283D,Q287D or CsA. Representative results from one of three independent experiments are shown. (B) Representative electron micrographs of control HIV-1 CA tubes, and tubes decorated with different TRIM5α or TRIMCypK283D,Q287D and negatively stained with Uranyl Acetate (UA) or Phosphotungstate (PTA). Scale bars are 50 nm.