Movie 1
Rhabdomere extension and the origin of rhabdomere trapezoids. This animation shows photoreceptor apical surfaces between the end of photoreceptor recruitment in the third instar eye disc, and the opening of the interrhabdomeral space (IRS) at approximately 50% of pupal development. R cell apical surfaces joined by zonula adherans (z.a.) junctions (magenta) are brought face-to-face in a trapped apical cavity by closure of cone cells (not shown) ‘above’ them. A stereotyped set of face-to-face contacts, notably including contact between R2/R4/R7, which displaces R3 from the ommatidial center, develops within the pocket. These contacts, together with the previously established z.a. contacts are maintained as photoreceptor apical surfaces extend to the retinal floor. At the completion of extension, face-to-face apical contacts are released, opening the IRS. R8, red; R2/R5, blue; R1/R3/R6, light green; R4, dark green; R7, yellow.
