CG33453

Review rationale: The source reports structural matches to macaque GM2 activator Q8HXX6, with TM-align scores approximately 0.59/0.55. Current target annotations identify DUF1091, not an experimentally established GM2-activator mechanism. A structurally similar secreted fold could bind lipids or proteins, but the exact claim requires evidence of direct stimulation of a defined enzyme. No target enzyme, activation assay or justified conserved interaction has been demonstrated for CG33453; secretion and a donor annotation alone are insufficient. No equivalent positive target annotation exists.

PATHWAY CONTEXT IGNORED

Review rationale: The structural donor for this prediction is human GM2 activator P17900. That protein presents ganglioside GM2 for lysosomal hydrolysis, a substrate-specific pathway that cannot be transferred solely from a moderate fold match. Primary lipid-analysis and transgenic-reconstitution work shows that gangliosides are not intrinsically detectable in ordinary Drosophila and must be induced using introduced synthesis enzymes and supplied precursor. This contradicts assignment of an endogenous ganglioside-catabolism role to native CG33453. It does not claim that flies cannot sialylate glycoproteins or that an engineered/exogenous substrate could never be degraded. No equivalent positive target annotation exists.