Figure 5.

Loss of 16 S polypeptides in the flagellar extracts of fla1 mutant cells at the restrictive temperature. Membrane plus matrix from fla1 mutant cells incubated at the permissive and restrictive temperatures of 23° and 33°C was fractionated on 11 ml 5–20% sucrose gradients in HMDEK buffer. Only the portion of the gradient from 20% (left) to 10% (right) is shown here on Coomassie-stained 7.5% gels. At 23°C, the IFT particle polypeptides, at 15–16 S, are reduced relative to wild type (arrowheads). These polypeptides are further depleted after incubation at 33°C (arrowheads). Similar results were obtained with membrane plus matrix isolated from fla8 and fla10 cells incubated at 23° and 33°C. Note that in the upper gel the polypeptides at 140 and 122 kD peak in the fraction highlighted by the 16 S arrow, whereas the other highlighted bands are sedimenting slightly slower.