Fig. 6. Rab5, Rab7 and Rab11 gene expression is required for normal third instar larvae nephrocyte ultrastructure and vesicle composition.
a-a” In wild type control nephrocytes the lysosomes are concentrated in the interior of the cell, surrounded by clear vacuoles. NSDs and lacunar channels are precisely arrayed around the cell periphery. b-b” Rab5 gene silencing eliminated NSDs, lacunar channels, vacuoles, and lysosomes. The basement membrane was substantially thickened (arrow, b”). c-c” Rab7 gene silencing led to the accumulation of large clear vacuoles, and absence of lysosomes. Lacunar channels were greatly reduced in size and morphologically abnormal (arrow, c’), while NSDs were mislocalized and structurally deformed (arrows, c”). d-d” Rab11 gene silencing dramatically increased the number of lysosomes, at the expense of large clear vacuoles. Lacunar channels and NSDs were virtually absent, except for occasional remnants (arrow, d”). Scale bars: 2 microns (a–d), 0.2 micron (a’–d’), and 0.05 micron (a”–d”).