PDZ domain 1 of amyloid-beta A4 precursor protein-binding family A member 1 (APBA1), APBA2, APBA3, and related domains
PDZ (PSD-95 (Postsynaptic density protein 95), Dlg (Discs large protein), and ZO-1 (Zonula occludens-1)) domain 1 of APBA1, APBA2, APBA3, and related domains. The APBA/X11/Mint protein family includes three members: neuron specific APBA1 (also known as X11alpha and Mint1) and APBA2 (also known as X11beta and Mint2), and the ubiquitously expressed APBA3 (also known as (X12gamma and Mint3). They are involved in regulating neuronal signaling, trafficking and plasticity. They contain two PDZ domains (PDZ1 and PDZ2) which bind a variety of proteins: Arf GTPases (APBA1 and APBA2 PDZ2) and neurexin (APBA1 and APBA2 PDZ1 and 2), which are involved in vesicle docking and exocytosis; alpha1B subunit of N-type Ca2+ channel (APBA1 PDZ1) that is involved in ion channels; KIF17 (APBA1 PDZ1) that is involved in transport and traffic; and Alzheimer's disease related proteins such as APP (APBA3 PDZ2), CCS (APBA1 PDZ2), NF-kappa-B/p65 (APBA2 PDZ2), presenilin-1 (APBA1 and APBA2 PDZ1 and PDZ2). PDZ domains usually bind in a sequence-specific manner to short peptide sequences located at the C-terminal end of their partner proteins (known as PDZ binding motifs). The PDZ superfamily includes canonical PDZ domains as well as those with circular permutations and domain swapping mediated by beta-strands. This APBA1,2,3-like family domain is a canonical PDZ domain containing six beta-strands A-F and two alpha-helices (alpha-helix 1 and 2), arranged as beta-strands A, B, C, alpha-helix 1, beta-strands D, E, alpha-helix 2 and beta- strand F.
Feature 1:peptide binding site [polypeptide binding site]
Evidence:
Comment:based on canonical PDZ domains with structure
Comment:PDZ domains specifically recognize and bind to short C-terminal peptide motifs, but can also recognize internal peptide motifs and certain lipids
Structure:1U3B: PDZ domain 1 of human APBA1 (in autoinhibited conformation) binds APBA1 C-terminal peptide; contacts at 4A
Comment:in this autoinhibited conformation the C-terminal tail of APBA1 folds back and inserts into the target-binding groove of the first PDZ domain; the binding of this tail occludes the binding of other target peptides
Jiyao W et al.(2023). "The conserved domain database in 2023.",