Figure 7.
The tetraspanin Sun is involved in the Gαq-dependent Rh1 endocytosis. (A) A Sun-null mutation suppressed the downregulation of Rh1 in light-exposed arr2 flies. (B) The light stimulation failed to induce Rh1 endocytosis in the sun;arr2 double mutant flies. (C) Sun protein was detected in the peripheral rhabdomeres of p[rh1∷Myc-Sun] flies. The R7 one (arrow) had negative staining. The TRP protein was labeled to show the locations of all rhabdomeres. Three Sun-enriched areas in the cell bodies are indicated by arrowheads. (D) An MBP-Gq fusion protein, not the MBP alone, pulled down Myc-Sun from the head extracts. Lane one was loaded with 1/5 of input. The western blot was probed with an Myc antibody. *Indicates that the sample is significantly different from others in the same group.