apb-1 — AP complex subunit beta (Q9N4F3, TrEMBL) — curation notes

Identity

apb-1 (Y71H2B.10) encodes the single large beta-adaptin of C. elegans. Unlike mammals, which have separate beta1 (AP-1) and beta2 (AP-2) subunits, the worm beta is shared between the AP-1 and AP-2 complexes PMID:23482940 PMID:23482940. The deep-research report (file:worm/apb-1/apb-1-deep-research-falcon.md) reaches the same conclusion and adds that GFP–APB-1 labels intestinal TGN-associated puncta with SMAP-1 (Wang et al. 2021, DOI 10.3389/fcell.2021.774401).
The AP-2 core describes apb-1 as the beta2 subunit PMID:23696751.

Beta-adaptin is the subunit that links the AP-2 core to clathrin via its hinge clathrin box PMID:10588660 PMID:23482940.
In AP-2, beta pairs with mu2 as a hemicomplex: APB-1::GFP and mu2 remain stable and localised at nerve-ring synapses and the oocyte plasma membrane in alpha-adaptin (apa-2) mutants, whereas beta is reduced in mu2 (apm-2) mutants but persists in AP-1 PMID:23482940 PMID:23482940.

Oocyte yolk uptake: beta-adaptin RNAi, like clathrin and alpha-adaptin RNAi, abolishes YP170::GFP uptake and produces embryonic defects PMID:10588660 PMID:19047463.
Apoptotic-cell clearance: apb-1 RNAi increases persistent germ-cell corpses, ~48% of which are not internalised; corpses are recognised by CED-1 and CED-6 normally but actin recruitment and phagosome maturation fail; APB-1 binds CED-6, DYN-1 and LST-4 directly in vitro PMID:23696751 PMID:23696751 PMID:23696751.
Synapses: the beta/mu2 hemicomplex retains partial AP-2 function in synaptic vesicle endocytosis; complete loss of AP-2 function requires removing both hemicomplexes PMID:23482940.

The AP-1 adaptor complex IBA and trans-Golgi network IBA are correct for this gene because the worm beta is shared with AP-1; they are not over-propagations.
AP-2 adaptor complex (GO:0030122) is missing from GOA and is proposed as NEW on the basis of the hemicomplex study (PMID:23482940) and the beta2 designation in PMID:23696751.
Generic protein binding (CED-6 IPI) is removed as uninformative; the interaction itself is not disputed.