BicD (Drosophila melanogaster, P16568) - curation notes

2026-09-27 session (claude-code)

Sources: UniProt P16568, GOA seed (39 rows), cached publications; Falcon deep research not yet available at time of writing.

BicD is a dimeric coiled-coil dynein activating adaptor PMID:38264934.
Egl + BicD are the minimal RNA-motor link; RNA licenses BicD to recruit dynein-dynactin [PMID:29944118 "A Bicaudal-D (BicD) adaptor protein and the RNA-binding protein Egalitarian (Egl) are sufficient for long-distance mRNA transport by the dynein motor and its accessory complex dynactin"; "The hairy RNA significantly increased the number of processive movements of dynein in the presence of dynactin and Egl/DmBicD"]. Drosophila BicD itself (DmBicD) was assayed, not only mouse BICD2.
Autoinhibition relieved by cargo PMID:32378283.
Egl, not BicD, binds the RNA PMID:19515976 -> supports the NOT mRNA binding row.
Cargo partners: Rab6/Rab2/Rab30/Rab39 GTP-dependent PMID:25453831, Chc direct PMID:20111007.
Synapse: kinetic role in SV recycling, not obligatory for endocytosis/exocytosis PMID:20111007.
Photoreceptor nuclear migration PMID:15582780 (abstract only); nervous system nuclear localization PMID:10559989.
Bristles, redundant with BicDR PMID:38264934.

protein binding x2 -> MODIFY to small GTPase binding (Rab6) and clathrin heavy chain binding (Chc).
GO:0140312 cargo adaptor activity -> MODIFY to GO:0008093; 0140312 is defined as a vesicle-coat (clathrin/COPII) adaptor.
GO:0048488 SV endocytosis -> MODIFY to GO:0036465 synaptic vesicle recycling (authors: not required for budding/uncoating).
GO:0050658 RNA transport -> MODIFY to GO:0051028 mRNA transport.
GO:0007312 oocyte nucleus migration (TAS, PMID:9642168 review on mRNA stability) -> UNDECIDED; same review also backs an egl TAS; only a tethering hypothesis found PMID:10825285.
Developmental outcomes (oocyte fate, egg chamber formation, oogenesis, chaeta development, MT polarization) -> KEEP_AS_NON_CORE.
NEW: GO:0140660 cytoskeletal motor activator activity (IDA, PMID:29944118); GO:0007097 nuclear migration (IMP, PMID:15582780). Comparator: Dhc64C has nuclear migration (IBA); human BICD2 has both as NEW.

Conserved: dynein adaptor + activator (GO:0008093/GO:0140660) as in BICD2; Rab6 Golgi cargo.
Fly-specific emphasis: Egl-mediated mRNA cargo; the nuclear cargo link used by BICD2 (RANBP2, nesprin-2) is not established for fly BicD in R-cell nuclear migration.

PMID:29944118, PMID:19515976, PMID:32378283, PMID:15582780, PMID:10825285, PMID:8951073 (all PubMed-verified via eutils before fetch).

Consistent with review. Adds Sladewski 2018 fly BicD-Egl-K10 reconstitution [file:DROME/BicD/BicD-deep-research-falcon.md "Addition of K10 mRNA opened the complex and produced robust minus-end-directed motility"], cited on the NEW GO:0140660 row; supports the NOT mRNA binding row ("BicD should not itself be annotated as the principal sequence-specific RNA-binding protein").
Also mentions BicD roles in female meiosis II and pronuclear fusion (Vazquez-Pianzola 2022) and FMRP as a partner; not cached or added, left for future curation.