Expressing Sec20^HMS01172 under the control of Scer\GAL4^pros-V1 leads to enlarged larval garland nephrocytes showing endocytosis/lysosomal/autophagy defects: late endosomes are enlarged (TEM and Rab7-positive puncta in fluorescence microscopy), but early endosomes have similar size and distribution as controls (Rbsn-5-positive puncta in fluorescence microscopy); endolysosomes are either small or aberrant (TEM); cargo is endocytosed but transported more slowly to the inner regions of the cell and accumulates in larger vesicles that do not become acidic as frequently as in controls.

Clonal expression of Sec20^HMS01172 under the control of Scer\GAL4^Act5C.PP (in combination with Dicer-2, for a more efficient RNAi) leads to larval fat cells showing autophagy defects: increase in abundance but decrease in size of autophagic vesicles (Atg8- and Lamp1-positive puncta in fluorescence microscopy, and TEM); presence of intact ER and mitochondria inside the autolysosomal lumen (TEM); accumulation of Golgi-like vesicles (GMAT puncta in fluorescence microscopy, and TEM); enlarged ER (TEM); but normal autophagosome-lysosome fusion (dual Atg8-, Lamp1-positive puncta in fluorescence microscopy).

Expressing Sec20^HMS01172 under the combined control of Scer\GAL4^fkh.PH abolishes glue granules in the larval salivary glands; in agreement, all of the (pre)pupae fell down from the wall of the culture vials.

Expressing Sec20^HMS01172 under the combined control of Scer\GAL4^GMR.PF and Scer\GAL4^ey.PU leads to darker eye color in adults.

The expression of Sec20^HMS01172 under the control of Scer\GAL4^{SPARC-MI00329-GAL4} (and Dicer-2, for a more efficient RNAi) in the larval fat body induces defective secretion, including intracellular matrix material, as shown by the retention of both secr.GFP and Vkg.GFP.