FAP100 and FAP73 assemble in various motility mutants and the mia mutants contain ODAs and IDAs. (A) Both FAP100 and FAP73 assemble in mutant axonemes that are missing the ODAs (oda1), I1 dynein (ida1), the single-headed IDAs a, c, d, and e (ida5), the N-DRC (pf3), the PP2A phosphatase (pf4), the RSs (pf14 and pf17), the CP (pf18), and the beaklike structures (mbo1 and mbo2). The proteins are also present in double mutants (oda1 × ida1, oda1 × ida2, and ida1 × ida5). (B) Immunoblots of subunits of the ODAs (IC69), I1 dynein (IC140 and IC97), the single-headed IDAs (actin and p28), and the RSs (RSP1) indicate these axonemal structures are apparently normal in both mia1 and mia2. The dynein subunits were detected on a single gel and blot, and RSP1 was detected on a second gel and blot. Ponceau staining of tubulin is shown as a loading control for each gel. (C) Silver-stained 3–5% urea gel of isolated axonemes demonstrates that dynein HC composition appears unaltered in mia mutants relative to wild type. Three lanes are from the same gel. The predicted molecular mass of I1 dynein HCs is the expected value: dynein HCs migrate significantly more slowly than the 250-kD molecular mass marker, which is shown well below the region of the gel shown. wt, wild type.