1kyu

From Proteopedia
Jump to navigation Jump to search

AP-2 CLATHRIN ADAPTOR ALPHA-APPENDAGE IN COMPLEX WITH EPS15 DPF PEPTIDEAP-2 CLATHRIN ADAPTOR ALPHA-APPENDAGE IN COMPLEX WITH EPS15 DPF PEPTIDE

Structural highlights

1kyu is a 2 chain structure with sequence from Mus musculus. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:X-ray diffraction, Resolution 1.8Å
Resources:FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

AP2A2_MOUSE 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 alpha subunit binds polyphosphoinositide-containing lipids, positioning AP-2 on the membrane. The AP-2 alpha subunit acts via its C-terminal appendage domain as a scaffolding platform for endocytic accessory proteins. The AP-2 alpha and AP-2 sigma subunits are thought to contribute to the recognition of the [ED]-X-X-X-L-[LI] motif.[1] [2] [3]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

Publication Abstract from PubMed

Clathrin-mediated endocytosis depends upon the interaction of accessory proteins with the alpha-ear of the AP-2 adaptor. We present structural characterization of these regulatory interactions. DPF and DPW motif peptides derived from eps15 and epsin bind in type I beta turn conformations to a conserved pocket on the alpha-ear platform. We show evidence for a second binding site that is DPW motif specific. The structure of a complex with an AP-2 binding segment from amphiphysin reveals a novel binding motif that we term FxDxF, which is engaged in an extended conformation by a unique surface of the platform domain. The FxDxF motif is also used by AP180 and the 170 kDa isoform of synaptojanin and can be found in several potential endocytic proteins, including HIP1, CD2AP, and PLAP. A mechanism of clathrin assembly regulation is suggested by three different AP-2 engagement modes.

Accessory protein recruitment motifs in clathrin-mediated endocytosis.,Brett TJ, Traub LM, Fremont DH Structure. 2002 Jun;10(6):797-809. PMID:12057195[4]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

See Also

References

  1. Gaidarov I, Keen JH. Phosphoinositide-AP-2 interactions required for targeting to plasma membrane clathrin-coated pits. J Cell Biol. 1999 Aug 23;146(4):755-64. PMID:10459011
  2. Nakatsu F, Ohno H. Adaptor protein complexes as the key regulators of protein sorting in the post-Golgi network. Cell Struct Funct. 2003 Oct;28(5):419-29. PMID:14745134
  3. Owen DJ, Collins BM, Evans PR. Adaptors for clathrin coats: structure and function. Annu Rev Cell Dev Biol. 2004;20:153-91. PMID:15473838 doi:10.1146/annurev.cellbio.20.010403.104543
  4. Brett TJ, Traub LM, Fremont DH. Accessory protein recruitment motifs in clathrin-mediated endocytosis. Structure. 2002 Jun;10(6):797-809. PMID:12057195

1kyu, resolution 1.80Å

Drag the structure with the mouse to rotate

Proteopedia Page Contributors and Editors (what is this?)Proteopedia Page Contributors and Editors (what is this?)

OCA