title: Structural Analysis and Deletion Mutagenesis Define Regions of QUIVER/SLEEPLESS that Are Responsible for Interactions with Shaker-Type Potassium Channels and Nicotinic Acetylcholine Receptors.
abstract: Ly6 proteins are endogenous prototoxins found in most animals. They show striking structural and functional parallels to snake α-neurotoxins, including regulation of ion channels and cholinergic signaling. However, the structural contributions of Ly6 proteins to regulation of effector molecules is poorly understood. This question is particularly relevant to the Ly6 protein QUIVER/SLEEPLESS (QVR/SSS), which has previously been shown to suppress excitability and synaptic transmission by upregulating potassium (K) channels and downregulating nicotinic acetylcholine receptors (nAChRs) in wake-promoting neurons to facilitate sleep in Drosophila. Using deletion mutagenesis, co-immunoprecipitations, ion flux assays, surface labeling and confocal microscopy, we demonstrate that only loop 2 is required for many of the previously described properties of SSS in transfected cells, including interactions with K channels and nAChRs. Collectively our data suggest that QVR/SSS, and by extension perhaps other Ly6 proteins, target effector molecules using limited protein motifs. Mapping these motifs may be useful in rational design of drugs that mimic or suppress Ly6-effector interactions to modulate nervous system function.
authors.affiliation: Department of Pharmacology, University of California San Diego, La Jolla, California, United States of America.
authors.forename: Meilin
authors.initials: M
authors.lastname: Wu
authors.affiliation: UCSD undergraduate program, Marshall College, University of California San Diego, La Jolla, California, United States of America.
authors.forename: Clifford Z
authors.initials: CZ
authors.lastname: Liu
authors.affiliation: Department of Pharmacology, University of California San Diego, La Jolla, California, United States of America.|Center for Circadian Biology, University of California San Diego, La Jolla, California, United States of America.
authors.forename: William J
authors.initials: WJ
authors.lastname: Joiner
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D029721:Drosophila Proteins / Q000737:chemistry* / Q000235:genetics*; D004331:Drosophila melanogaster / Q000378:metabolism*; D008565:Membrane Proteins; D008958:Models, Molecular; D016296:Mutagenesis / Q000235:genetics*; D015221:Potassium Channels / Q000737:chemistry* / Q000235:genetics*; D011485:Protein Binding; D021381:Protein Transport; D011978:Receptors, Nicotinic / Q000378:metabolism*; D017384:Sequence Deletion / Q000235:genetics*; D051637:Shaker Superfamily of Potassium Channels / Q000378:metabolism*; D013329:Structure-Activity Relationship
chemical_list: D029721:Drosophila Proteins; D008565:Membrane Proteins; D015221:Potassium Channels; C530371:Qvr protein, Drosophila; D011978:Receptors, Nicotinic; D051637:Shaker Superfamily of Potassium Channels
references.citation: J Immunol. 1993 Jun 15;150(12):5379-90
references.pmid: 8515066
references.citation: AAPS J. 2009 Mar;11(1):167-77
references.pmid: 19280351
references.citation: J Neurogenet. 2010 Jul;24(2):67-74
references.pmid: 20429677
references.citation: Proc Natl Acad Sci U S A. 2009 Mar 17;106(11):4477-82
references.pmid: 19246390
references.citation: J Leukoc Biol. 2013 Oct;94(4):585-94
references.pmid: 23543767
references.citation: Nature. 2005 Apr 28;434(7037):1087-92
references.pmid: 15858564
references.citation: Cell Prolif. 2008 Oct;41(5):726-38
references.pmid: 18823497
references.citation: Transpl Immunol. 2002 May;9(2-4):93-6
references.pmid: 12180852
references.citation: Curr Biol. 2014 Mar 17;24(6):621-9
references.pmid: 24613312
references.citation: Nat Neurosci. 2007 Aug;10(8):953-62
references.pmid: 17643119
references.citation: Br J Dermatol. 2015 Oct;173(4):1066-9
references.pmid: 25919322
references.citation: Exp Hematol. 2005 Jul;33(7):836-43
references.pmid: 15963860
references.citation: Trends Pharmacol Sci. 2015 Feb;36(2):109-23
references.pmid: 25528970
references.citation: J Biol Chem. 2015 Oct 2;290(40):24509-18
references.pmid: 26276394
references.citation: Protein Sci. 2006 Oct;15(10):2244-56
references.pmid: 17008713
references.citation: Science. 2010 Nov 26;330(6008):1238-40
references.pmid: 21071629
references.citation: Cell Mol Life Sci. 2008 Nov;65(21):3481-93
references.pmid: 18821057
references.citation: Hum Mol Genet. 2003 Nov 15;12(22):3017-24
references.pmid: 14506129
references.citation: Biotechniques. 1993 Nov;15(5):906-11
references.pmid: 7505602
references.citation: Nat Neurosci. 2010 Jan;13(1):69-75
references.pmid: 20010822
references.citation: J Neurosci. 2011 Aug 3;31(31):11387-95
references.pmid: 21813698
references.citation: J Biol Chem. 2013 May 31;288(22):15888-99
references.pmid: 23585571
references.citation: Neurochem Int. 2012 Dec;61(7):1212-9
references.pmid: 22989685
references.citation: Science. 2008 Jul 18;321(5887):372-6
references.pmid: 18635795
references.citation: Mol Pharmacol. 2005 Dec;68(6):1839-51
references.pmid: 16183856
references.citation: J Neurosci. 2015 Feb 25;35(8):3420-30
references.pmid: 25716842
references.citation: Toxins (Basel). 2013 Jul;5(7):1314-31
references.pmid: 23881252
references.citation: J Neurosci. 2012 Feb 8;32(6):2227-38
references.pmid: 22323734
references.citation: J Neurosci. 2000 Aug 15;20(16):5958-64
references.pmid: 10934243
references.citation: J Leukoc Biol. 2009 Jan;85(1):55-63
references.pmid: 18927400
references.citation: J Biol Chem. 2011 Mar 25;286(12):10618-27
references.pmid: 21252236
references.citation: J Mol Biol. 2005 Mar 4;346(4):967-89
references.pmid: 15701510
references.citation: EMBO J. 2005 Apr 20;24(8):1512-22
references.pmid: 15791209
references.citation: FASEB J. 2011 Apr;25(4):1156-65
references.pmid: 21156809
references.citation: Science. 2005 Aug 5;309(5736):897-903
references.pmid: 16002581
references.citation: J Biol Chem. 2014 Jul 11;289(28):19491-9
references.pmid: 24847059
references.citation: 3 Biotech. 2012 Mar;2(1):37-52
references.pmid: 22582156