# ATP6V0C Review Notes

## 2026-06-03 - Proteostasis PN re-review

Falcon deep research was already present and was used for this PN pass. It supports the core identity of ATP6V0C as the V0-sector c proteolipid/c-ring component of human V-ATPase [file:human/ATP6V0C/ATP6V0C-deep-research-falcon.md "ATP6V0C encodes the c proteolipid subunit of the membrane Vo sector of the V‑type H+‑ATPase (V‑ATPase) in Homo sapiens"]. The primary structural paper supports the same mechanism: V-ATPases are "ATP-driven proton pumps comprised of a cytoplasmic V1 complex for ATP hydrolysis and a membrane-embedded Vo complex for proton transfer" [PMID:33065002 "Vesicular- or vacuolar-type adenosine triphosphatases (V-ATPases) are ATP-driven proton pumps comprised of a cytoplasmic V1 complex for ATP hydrolysis and a membrane-embedded Vo complex for proton transfer"].

The PN projection has three ATP6V0C rows. `GO:0007042 lysosomal lumen acidification` and `GO:0033179 proton-transporting V-type ATPase, V0 domain` are already present in GOA and remain accepted. The only projection that is more specific than existing GOA is `GO:0046610 lysosomal proton-transporting V-type ATPase, V0 domain`, from the PN leaf `Autophagy-Lysosome Pathway > Pre-initiation autophagy signaling > mTORC1 pathway, upstream > Nutrient sensing > V0 lysosomal v-ATPase proton pump component` [projects/PROTEOSTASIS/reports/pn_projection/pn_projected_annotations.tsv "This PN leaf is restricted to V0-sector lysosomal V-ATPase components. The GO lysosomal V0-domain component term is the direct target."].

Curation conclusion: add `GO:0046610` as `NEW` because it is a conservative lysosome-specific cellular-component refinement supported by the combination of V0-domain membership and lysosomal membrane/acidification evidence. Do not add broad autophagy-initiation, macroautophagy-regulation, or mTORC1-process terms from the PN context alone. For ATP6V0C, those pathway effects are best treated as consequences of the core lysosomal proton-pump/acidification function [PMID:33065002 "Vesicular and organellar V-ATPases are essential in establishing and maintaining the pH homeostasis of endosomes and lysosomes"] and Falcon likewise frames autophagic cargo degradation as acidification-dependent [file:human/ATP6V0C/ATP6V0C-deep-research-falcon.md "V‑ATPase‑driven acidification is essential for lysosomal hydrolase activity and endocytic/autophagic cargo degradation"].