title: Enhanced selectivity for sulfatide by engineered human glycolipid transfer protein.
abstract: Human glycolipid transfer protein (GLTP) fold represents a novel structural motif for lipid binding/transfer and reversible membrane translocation. GLTPs transfer glycosphingolipids (GSLs) that are key regulators of cell growth, division, surface adhesion, and neurodevelopment. Herein, we report structure-guided engineering of the lipid binding features of GLTP. New crystal structures of wild-type GLTP and two mutants (D48V and A47D‖D48V), each containing bound N-nervonoyl-sulfatide, reveal the molecular basis for selective anchoring of sulfatide (3-O-sulfo-galactosylceramide) by D48V-GLTP. Directed point mutations of "portal entrance" residues, A47 and D48, reversibly regulate sphingosine access to the hydrophobic pocket via a mechanism that could involve homodimerization. "Door-opening" conformational changes by phenylalanines within the hydrophobic pocket are revealed during lipid encapsulation by new crystal structures of bona fide apo-GLTP and GLTP complexed with N-oleoyl-glucosylceramide. The development of "engineered GLTPs" with enhanced specificity for select GSLs provides a potential new therapeutic approach for targeting GSL-mediated pathologies.
authors.affiliation: Structural Biology Unit, CIC bioGUNE, Technology Park of Bizkaia, 48160 Derio-Bilbao, Spain.
authors.forename: Valeria R
authors.initials: VR
authors.lastname: Samygina
authors.forename: Alexander N
authors.initials: AN
authors.lastname: Popov
authors.forename: Aintzane
authors.initials: A
authors.lastname: Cabo-Bilbao
authors.forename: Borja
authors.initials: B
authors.lastname: Ochoa-Lizarralde
authors.forename: Felipe
authors.initials: F
authors.lastname: Goni-de-Cerio
authors.forename: Xiuhong
authors.initials: X
authors.lastname: Zhai
authors.forename: Julian G
authors.initials: JG
authors.lastname: Molotkovsky
authors.forename: Dinshaw J
authors.initials: DJ
authors.lastname: Patel
authors.forename: Rhoderick E
authors.initials: RE
authors.lastname: Brown
authors.forename: Lucy
authors.initials: L
authors.lastname: Malinina
mesh_terms: D019943:Amino Acid Substitution; D001665:Binding Sites; D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics; D018360:Crystallography, X-Ray; D006801:Humans; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D011485:Protein Binding; D055503:Protein Multimerization; D013379:Substrate Specificity; D013433:Sulfoglycosphingolipids / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D002352:Carrier Proteins; C511922:GLTP protein, human; D013433:Sulfoglycosphingolipids
references.citation: Science. 2011 Feb 4;331(6017):589-92
references.pmid: 21292977
references.citation: Nature. 2004 Aug 26;430(7003):1048-53
references.pmid: 15329726
references.citation: J Biol Chem. 2010 Apr 23;285(17):13066-78
references.pmid: 20164530
references.citation: Proc Natl Acad Sci U S A. 2003 Jan 7;100(1):38-43
references.pmid: 12518053
references.citation: PLoS Biol. 2006 Nov;4(11):e362
references.pmid: 17105344
references.citation: Acta Crystallogr D Biol Crystallogr. 1997 May 1;53(Pt 3):240-55
references.pmid: 15299926
references.citation: J Mol Biol. 2006 Jan 13;355(2):224-36
references.pmid: 16309699
references.citation: J Neurochem. 2005 Nov;95(3):609-17
references.pmid: 16086686
references.citation: Experientia. 1990 Jun 15;46(6):611-6
references.pmid: 2193825
references.citation: Biochim Biophys Acta. 2007 Jun;1771(6):746-60
references.pmid: 17320476
references.citation: Biophys J. 2010 Oct 20;99(8):2626-35
references.pmid: 20959104
references.citation: J Exp Med. 2005 Dec 5;202(11):1517-26
references.pmid: 16314439
references.citation: Anal Biochem. 1999 Mar 15;268(2):297-304
references.pmid: 10075820
references.citation: J Biol Chem. 2005 Jul 15;280(28):26312-20
references.pmid: 15901739
references.citation: Curr Opin Struct Biol. 2007 Oct;17(5):521-9
references.pmid: 17951048
references.citation: J Immunol. 2008 Dec 1;181(11):8077-87
references.pmid: 19018000
references.citation: J Neurochem. 2007 Nov;103 Suppl 1:171-9
references.pmid: 17986152
references.citation: Biochem J. 2008 Feb 15;410(1):81-92
references.pmid: 17939778
references.citation: Nat Chem Biol. 2009 Jul;5(7):508-14
references.pmid: 19525967
references.citation: Nat Struct Mol Biol. 2009 Dec;16(12):1294-301
references.pmid: 19898476
references.citation: Neurochem Res. 2007 Feb;32(2):257-62
references.pmid: 17006761
references.citation: Acta Crystallogr D Biol Crystallogr. 1993 Jan 1;49(Pt 1):129-47
references.pmid: 15299554
references.citation: Biochim Biophys Acta. 1992 Dec 11;1113(3-4):375-89
references.pmid: 1450207
references.citation: Biochim Biophys Acta. 2010 Aug;1801(8):774-83
references.pmid: 20117236
references.citation: Nat Immunol. 2003 Aug;4(8):808-15
references.pmid: 12833155
references.citation: Proc Natl Acad Sci U S A. 2011 Jan 11;108(2):498-503
references.pmid: 21187418
references.citation: Mol Neurobiol. 2008 Apr-Jun;37(2-3):93-103
references.pmid: 18465098