Structural highlights
Function
[GGA1_HUMAN] Plays a role in protein sorting and trafficking between the trans-Golgi network (TGN) and endosomes. Mediates the ARF-dependent recruitment of clathrin to the TGN and binds ubiquitinated proteins and membrane cargo molecules with a cytosolic acidic cluster-dileucine (AC-LL) motif.[1] [BACE1_HUMAN] Responsible for the proteolytic processing of the amyloid precursor protein (APP). Cleaves at the N-terminus of the A-beta peptide sequence, between residues 671 and 672 of APP, leads to the generation and extracellular release of beta-cleaved soluble APP, and a corresponding cell-associated C-terminal fragment which is later released by gamma-secretase.[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
BACE (beta-site amyloid precursor protein cleaving enzyme, beta-secretase) is a type-I membrane protein which functions as an aspartic protease in the production of beta-amyloid peptide, a causative agent of Alzheimer's disease. Its cytoplasmic tail has a characteristic acidic-cluster dileucine motif recognized by the VHS domain of adaptor proteins, GGAs (Golgi-localizing, gamma-adaptin ear homology domain, ARF-interacting). Here we show that BACE is colocalized with GGAs in the trans-Golgi network and peripheral structures, and phosphorylation of a serine residue in the cytoplasmic tail enhances interaction with the VHS domain of GGA1 by about threefold. The X-ray crystal structure of the complex between the GGA1-VHS domain and the BACE C-terminal peptide illustrates a similar recognition mechanism as mannose 6-phosphate receptors except that a glutamine residue closes in to fill the gap created by the shorter BACE peptide. The serine and lysine of the BACE peptide point their side chains towards the solvent. However, phosphorylation of the serine affects the lysine side chain and the peptide backbone, resulting in one additional hydrogen bond and a stronger electrostatic interaction with the VHS domain, hence the reversible increase in affinity.
Insights into the phosphoregulation of beta-secretase sorting signal by the VHS domain of GGA1.,Shiba T, Kametaka S, Kawasaki M, Shibata M, Waguri S, Uchiyama Y, Wakatsuki S Traffic. 2004 Jun;5(6):437-48. PMID:15117318[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Puertollano R, Randazzo PA, Presley JF, Hartnell LM, Bonifacino JS. The GGAs promote ARF-dependent recruitment of clathrin to the TGN. Cell. 2001 Apr 6;105(1):93-102. PMID:11301005
- ↑ Lin X, Koelsch G, Wu S, Downs D, Dashti A, Tang J. Human aspartic protease memapsin 2 cleaves the beta-secretase site of beta-amyloid precursor protein. Proc Natl Acad Sci U S A. 2000 Feb 15;97(4):1456-60. PMID:10677483
- ↑ Okada H, Zhang W, Peterhoff C, Hwang JC, Nixon RA, Ryu SH, Kim TW. Proteomic identification of sorting nexin 6 as a negative regulator of BACE1-mediated APP processing. FASEB J. 2010 Aug;24(8):2783-94. doi: 10.1096/fj.09-146357. Epub 2010 Mar 30. PMID:20354142 doi:10.1096/fj.09-146357
- ↑ Shiba T, Kametaka S, Kawasaki M, Shibata M, Waguri S, Uchiyama Y, Wakatsuki S. Insights into the phosphoregulation of beta-secretase sorting signal by the VHS domain of GGA1. Traffic. 2004 Jun;5(6):437-48. PMID:15117318 doi:10.1111/j.1600-0854.2004.00188.x
