twr review notes

UniProt O97066 (Signal peptidase complex catalytic subunit SEC11); peptidase S26B; PANTHER PTHR10806. Called Spase18/21 in PMID:23573290.

Literature journal

• Fly SPC composition PMID:23573290
• SPC role PMID:23573290
• No twr-specific experimental study is cached; HDA rows come from organelle proteomics (PMID:19317464) and serine hydrolase activity profiling (PMID:33827210), both abstract-only here.

Curation decisions (SPC module, applied to twr, Spase12, Spase22-23, Spase25)

• GO:0005787 signal peptidase complex ACCEPTED for all subunits; GO:0005789 ER membrane ACCEPTED; membrane / endomembrane system / ER -> MODIFY to ER membrane.
• GO:0051604 protein maturation -> MODIFY to GO:0016485 protein processing (GO:0006465 signal peptide processing is obsolete and was redirected to protein maturation; protein processing is the more specific valid child).
• IBA protein targeting to ER -> REMOVE (SPC acts after targeting), as in the human SPCS1-3 reviews.
• twr: signal peptidase activity is the core MF; peptidase activity -> MODIFY to signal peptidase activity; serine hydrolase activity -> MODIFY to serine-type endopeptidase activity (kept, mechanism term). Accessory subunits: contributes_to signal peptidase activity.

Deep research

twr-deep-research-falcon.md (falcon) arrived after the review was first committed. It identifies twr (tower, CG2358) as Spase18/21, the locus genetically confirmed in a 2010 Genome Research allele-mapping study (not cached here). It agrees that TWR is the SEC11-family catalytic subunit of the ER signal peptidase complex. Fly microsomes cleave signal peptides in vitro, but no study isolates TWR activity or lists its substrates. No annotation decision changed.