| Structural highlights
Function
[SNX17_HUMAN] Critical regulator of endosomal recycling of numerous receptors, channels, and other transmembrane proteins. Binds to NPxY sequences in the cytoplasmic tails of target cargos. Plays a role in the sorting of endocytosed LRP1 and APP, and prevents their degradation. Required for maintenance of normal cell surface levels of APP and LRP1. Recycles internalized integrins ITGB1, ITGB5 and their associated alpha subunits, preventing them from lysosomal degradation. Interacts with membranes containing phosphatidylinositol 3-phosphate (PtdIns(3P)).[1] [2] [3] [4] [5] [6]
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
Following endocytosis, the fates of receptors, channels, and other transmembrane proteins are decided via specific endosomal sorting pathways, including recycling to the cell surface for continued activity. Two distinct phox-homology (PX)-domain-containing proteins, sorting nexin (SNX) 17 and SNX27, are critical regulators of recycling from endosomes to the cell surface. In this study we demonstrate that SNX17, SNX27, and SNX31 all possess a novel 4.1/ezrin/radixin/moesin (FERM)-like domain. SNX17 has been shown to bind to Asn-Pro-Xaa-Tyr (NPxY) sequences in the cytoplasmic tails of cargo such as LDL receptors and the amyloid precursor protein, and we find that both SNX17 and SNX27 display similar affinities for NPxY sorting motifs, suggesting conserved functions in endosomal recycling. Furthermore, we show for the first time that all three proteins are able to bind the Ras GTPase through their FERM-like domains. These interactions place the PX-FERM-like proteins at a hub of endosomal sorting and signaling processes. Studies of the SNX17 PX domain coupled with cellular localization experiments reveal the mechanistic basis for endosomal localization of the PX-FERM-like proteins, and structures of SNX17 and SNX27 determined by small angle X-ray scattering show that they adopt non-self-assembling, modular structures in solution. In summary, this work defines a novel family of proteins that participate in a network of interactions that will impact on both endosomal protein trafficking and compartment specific Ras signaling cascades.
Phox homology band 4.1/ezrin/radixin/moesin-like proteins function as molecular scaffolds that interact with cargo receptors and Ras GTPases.,Ghai R, Mobli M, Norwood SJ, Bugarcic A, Teasdale RD, King GF, Collins BM Proc Natl Acad Sci U S A. 2011 Apr 21. PMID:21512128[7]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Williams R, Schluter T, Roberts MS, Knauth P, Bohnensack R, Cutler DF. Sorting nexin 17 accelerates internalization yet retards degradation of P-selectin. Mol Biol Cell. 2004 Jul;15(7):3095-105. Epub 2004 Apr 30. PMID:15121882 doi:10.1091/mbc.E04-02-0143
- ↑ Knauth P, Schluter T, Czubayko M, Kirsch C, Florian V, Schreckenberger S, Hahn H, Bohnensack R. Functions of sorting nexin 17 domains and recognition motif for P-selectin trafficking. J Mol Biol. 2005 Apr 8;347(4):813-25. PMID:15769472 doi:S0022-2836(05)00144-0
- ↑ Czubayko M, Knauth P, Schluter T, Florian V, Bohnensack R. Sorting nexin 17, a non-self-assembling and a PtdIns(3)P high class affinity protein, interacts with the cerebral cavernous malformation related protein KRIT1. Biochem Biophys Res Commun. 2006 Jul 7;345(3):1264-72. Epub 2006 May 2. PMID:16712798 doi:10.1016/j.bbrc.2006.04.129
- ↑ Donoso M, Cancino J, Lee J, van Kerkhof P, Retamal C, Bu G, Gonzalez A, Caceres A, Marzolo MP. Polarized traffic of LRP1 involves AP1B and SNX17 operating on Y-dependent sorting motifs in different pathways. Mol Biol Cell. 2009 Jan;20(1):481-97. doi: 10.1091/mbc.E08-08-0805. Epub 2008 Nov, 12. PMID:19005208 doi:10.1091/mbc.E08-08-0805
- ↑ Steinberg F, Heesom KJ, Bass MD, Cullen PJ. SNX17 protects integrins from degradation by sorting between lysosomal and recycling pathways. J Cell Biol. 2012 Apr 16;197(2):219-30. doi: 10.1083/jcb.201111121. Epub 2012 Apr, 9. PMID:22492727 doi:10.1083/jcb.201111121
- ↑ Ghai R, Mobli M, Norwood SJ, Bugarcic A, Teasdale RD, King GF, Collins BM. Phox homology band 4.1/ezrin/radixin/moesin-like proteins function as molecular scaffolds that interact with cargo receptors and Ras GTPases. Proc Natl Acad Sci U S A. 2011 Apr 21. PMID:21512128 doi:10.1073/pnas.1017110108
- ↑ Ghai R, Mobli M, Norwood SJ, Bugarcic A, Teasdale RD, King GF, Collins BM. Phox homology band 4.1/ezrin/radixin/moesin-like proteins function as molecular scaffolds that interact with cargo receptors and Ras GTPases. Proc Natl Acad Sci U S A. 2011 Apr 21. PMID:21512128 doi:10.1073/pnas.1017110108
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