AP-2 complex subunit beta - P63010 (AP2B1_HUMAN)


Protein Feature View of PDB entries mapped to a UniProtKB sequence  

Component of the adaptor protein complex 2 (AP-2). Adaptor protein complexes function in protein transport via transport vesicles in different membrane traffic pathways. Adaptor protein complexes are vesicle coat components and appear to be involved in cargo selection and vesicle formation. AP-2 is involved in clathrin-dependent endocytosis in which cargo proteins are incorporated into vesicles surrounded by clathrin (clathrin-coated vesicles, CCVs) which are destined for fusion with the early endosome. The clathrin lattice serves as a mechanical scaffold but is itself unable to bind directly to membrane components. Clathrin-associated adaptor protein (AP) complexes which can bind directly to both the clathrin lattice and to the lipid and protein components of membranes are considered to be the major clathrin adaptors contributing the CCV formation. AP-2 also serves as a cargo receptor to selectively sort the membrane proteins involved in receptor-mediated endocytosis. AP-2 seems to play a role in the recycling of synaptic vesicle membranes from the presynaptic surface. AP-2 recognizes Y-X-X-[FILMV] (Y-X-X-Phi) and [ED]-X-X-X-L-[LI] endocytosis signal motifs within the cytosolic tails of transmembrane cargo molecules. AP-2 may also play a role in maintaining normal post-endocytic trafficking through the ARF6-regulated, non-clathrin pathway. The AP-2 beta subunit acts via its C-terminal appendage domain as a scaffolding platform for endocytic accessory proteins; at least some clathrin-associated sorting proteins (CLASPs) are recognized by their [DE]-X(1,2)-F-X-X-[FL]-X-X-X-R motif. The AP-2 beta subunit binds to clathrin heavy chain, promoting clathrin lattice assembly; clathrin displaces at least some CLASPs from AP2B1 which probably then can be positioned for further coat assembly. UniProt
Pathway Maps
      ESCHER  BiGG
Subunit Structure
Adaptor protein complex 2 (AP-2) is a heterotetramer composed of two large adaptins (alpha-type subunit AP2A1 or AP2A2 and beta-type subunit AP2B1), a medium adaptin (mu-type subunit AP2M1) and a small adaptin (sigma-type subunit AP2S1) (PubMed:12086608, PubMed:19140243). Interacts with EPN1 (PubMed:10944104, PubMed:16516836). Interacts with EPS15; clathrin competes with EPS15 (PubMed:10944104, PubMed:16903783). Interacts with SNAP91; clathrin competes with SNAP91 (PubMed:10944104, PubMed:16516836, PubMed:16903783). Interacts with CLTC; clathrin competes with EPS15, SNAP91 and PIP5K1C (PubMed:10944104). Interacts with LDLRAP1 (PubMed:15728179, PubMed:16516836, PubMed:16903783). Interacts with AMPH and BIN1 (PubMed:16516836, PubMed:16903783). Interacts with ARF6 (GDP-bound) (PubMed:17719203). Interacts (dephosphorylated at Tyr-737) with ARRB1; phosphorylation of AP2B1 at Tyr-737 disrupts the interaction (PubMed:11777907, PubMed:16516836, PubMed:17456551, PubMed:16903783). Interacts with SLC2A8 (PubMed:16723738). Interacts with SCYL1 and SCYL2 (PubMed:16903783). Interacts with TGFBR1 and TGFBR2 (PubMed:12429842). Interacts with PIP5K1C; clathrin competes with PIP5K1C (By similarity). Interacts with DENND1B, but not with DENND1A, nor DENND1C (PubMed:20154091). Interacts with FCHO1 (PubMed:22484487). Interacts with RFTN1 (PubMed:27022195). Interacts with KIAA1107 (PubMed:29262337). UniProt
The Protein Feature View requires a browser that supports SVG (Scalable Vector Graphics). Mouse over tracks and labels for more information.
Data origin/color codes
The vertical color bar on the left side indicates data provenance.
Data in green originates from UniProtKB  
Variation data (sourced from UniProt) shows non-genetic variation from the ExPASy   and dbSNP   websites.
Data in yellow originates from Pfam  , by interacting with the HMMER3 web site  
Data in purple originates from Phosphosite  .
Data in orange originates from the SCOP   (version 1.75) and SCOPe   (version 2.04) classifications.
Data in grey has been calculated using BioJava  . Protein disorder predictions are based on JRONN (Troshin, P. and Barton, G. J. unpublished), a Java implementation of RONN  
  • Red: potentially disorderd region
  • Blue: probably ordered region.
Hydropathy has been calculated using a sliding window of 15 residues and summing up scores from standard hydrophobicity tables.
  • Red: hydrophobic
  • Blue: hydrophilic.
Data in lilac represent the genomic exon structure projected onto the UniProt sequence.
Data in blue originates from PDB
  • Secstruc: Secondary structure projected from representative PDB entries onto the UniProt sequence.
Sequence Mismatches It is now possible to see information about expression tags, cloning artifacts, and many other details related to sequence mismatches.
Icons represent a number of different sequence modifications that can be observed in PDB files. For example the 'T' icon T represents expression tags that have been added to the sequence. The 'E' icon E represents an engineered mutation. However, besides these two, there are many other icons. For more information about the meaning and exact position of a sequence modification, move the cursor over the icon.
Validation Track

For more details on the Validation Track (Structure Summary Page only) see the dedicated help page.

Data in red indicates combined ranges of Homology Models from the SWISS-MODEL Repository  
The PDB to UniProt mapping is based on the data provided by the EBI SIFTS project. See also Velankar et al., Nucleic Acids Research 33, D262-265 (2005).
Organism icons generated by flaticon.com under CC BY. The authors are: Freepik, Icons8, OCHA, Scott de Jonge.

For more details on the Protein Feature view see the dedicated help page.