Fig. 7. Dominant-negative Rab11 inhibits TRP and Rh1 transport, and disperses RLVs and MVBs. (A) Wild-type rhabdomeres are TRP immunopositive at 64% pd. (B) Rab11^N124I expression beginning at 50% pd prevents TRP transport to the rhabdomere; TRP is dispersed throughout photoreceptor cytoplasm. (C) There is no TRP containing vesicles in Rab5^N142I-expressing cells, but TRP is normally transported to the rhabdomere. (D) Rab11^N124I and Rab5^N142I co-expression beginning at 50% pd prevents TRP transport to the rhabdomere. (E) Wild-type rhabdomeres are Rh1 immunopositive at 83% pd; cytoplasmic Rh1 is present in RLVs. (F) Rab11^N124I expression beginning at 70% pd prevents Rh1 transport to the rhabdomere. RLVs are lost and Rh1 accumulates diffusely throughout photoreceptors. (G) RLVs are absent in Rab5^N142I-expressing cells, but Rh1 is normally transported to the rhabdomere. (H) Rab11^N124I and Rab5^N142I co-expression beginning at 70% pd prevents Rh1 transport to the rhabdomere. RLVs are lost and Rh1 accumulates diffusely throughout photoreceptors, similar to Rab11^N124I single expression. (I,J) Golgi morphologies are not affected by Rab11^N124I expression. (K-N) Electron micrographs of 65% pd pupae heat shocked from 50% pd (K,L) or 83% pd pupae heat shocked from 70% pd (M,N). Rab11^N124I expression reduces rhabdomere size and causes proliferation of abnormal cytoplasmic vesicles (arrowheads). MVBs are evident in control photoreceptors (arrows), but are absent in photoreceptors expressing Rab11^N124I. IRS is reduced by Rab11^N124I expression. (O) Rab11^N124I expression decreases RLVs and MVBs in parallel (see Materials and methods). Scale bar: 2 µm in A-N.