vclb notes (Danio rerio, vinculin b; UniProt A0A0S2I7K2)

2026-09-28 — session log

Deep research: FAILED for this gene (Edison/Falcon returned 402 Payment Required; the OpenAI key is
invalid). Not retried, per instructions. No -deep-research-*.md file exists; literature research was done
manually (cached publications, Europe PMC). See also ../vcla/vcla-notes.md for shared pair literature and
../vcla/vcla-bioinformatics/RESULTS.md for the protein comparison.

Accession A0A0S2I7K2 (TrEMBL, 1066 aa; EMBL ALO18748 from Cheng & Zhang) = vinculin-type isoform (no
metavinculin insert). ZFIN:ZDB-GENE-131017-1. vclb was unannotated in Zv9 and cloned by Han et al.
PMID:28767718

Protein

• Y822F: PMID:28767718
• Y822F does not block junction localization in MDCK: PMID:28767718
• But Han note endogenous vinculin was present in their cells: PMID:28767718
• Confirmed Y822->F at vclb position 822 by my alignment.

Expression

• Predominant copy in embryonic heart: PMID:30635353
• Epicardium: vcla absent there PMID:27578788
• Endothelium: PMID:36314606
• Broad: PMID:38697108
• Maternal: little PMID:28767718

Mutants

• Cheng 2016 gene-trap (abstract only): epicardial hyperplasia, coronary defects, juvenile death, FAK/ERK up.
• Han 2017 hu11202 (7-bp del, PTC at 22). Possible downstream M26 start noted by the authors.
• Gunawan 2019 bns247 (16-bp del): no strong valve defect; not surviving to adulthood PMID:30635353
• vclb is the adapting gene for vcla PTC alleles (see vcla notes; PMID:30944477, PMID:36427314). No study tested whether vcla is upregulated in vclb mutants.

Decisions

• Shared IEA/IBA rows handled identically to vcla (same text), except beta-catenin binding IBA -> UNDECIDED
  because of F822 (target-specific residue change at a residue linked to that interaction; untested).
• heart development, coronary vasculature morphogenesis IMP: ACCEPT (copy-specific by expression).
• NEW GO:0061028 establishment of endothelial barrier (IGI, PMID:36260739) on both copies.