title: Evolution of crystallins for a role in the vertebrate eye lens.
abstract: The camera eye lens of vertebrates is a classic example of the re-engineering of existing protein components to fashion a new device. The bulk of the lens is formed from proteins belonging to two superfamilies, the α-crystallins and the βγ-crystallins. Tracing their ancestry may throw light on the origin of the optics of the lens. The α-crystallins belong to the ubiquitous small heat shock proteins family that plays a protective role in cellular homeostasis. They form enormous polydisperse oligomers that challenge modern biophysical methods to uncover the molecular basis of their assembly structure and chaperone-like protein binding function. It is argued that a molecular phenotype of a dynamic assembly suits a chaperone function as well as a structural role in the eye lens where the constraint of preventing protein condensation is paramount. The main cellular partners of α-crystallins, the β- and γ-crystallins, have largely been lost from the animal kingdom but the superfamily is hugely expanded in the vertebrate eye lens. Their structures show how a simple Greek key motif can evolve rapidly to form a complex array of monomers and oligomers. Apart from remaining transparent, a major role of the partnership of α-crystallins with β- and γ-crystallins in the lens is to form a refractive index gradient. Here, we show some of the structural and genetic features of these two protein superfamilies that enable the rapid creation of different assembly states, to match the rapidly changing optical needs among the various vertebrates.
authors: Department of Biological Sciences, Crystallography, Institute of Structural and Molecular Biology, Birkbeck College, Malet Street, London WC1E 7HX, United Kingdom. C.Slingsby@mail.cryst.bbk.ac.uk
authors: Christine
authors: C
authors: Slingsby
authors: Graeme J
authors: GJ
authors: Wistow
authors: Alice R
authors: AR
authors: Clark
mesh_terms: D000818:Animals; D003459:Crystallins / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*; D005399:Fishes; D006801:Humans; D007908:Lens, Crystalline / Q000737:chemistry* / Q000502:physiology*; D051379:Mice; D008958:Models, Molecular; D018832:Molecular Chaperones / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*; D012031:Refractometry
chemical_list: D003459:Crystallins; D018832:Molecular Chaperones
references: FASEB J. 2010 Oct;24(10):3633-42
references: 20501794
references: J Comp Neurol. 2004 Jul 12;475(1):70-82
references: 15176085
references: J Clin Invest. 2009 Jul;119(7):1837-48
references: 19587458
references: Nat Struct Biol. 2001 Dec;8(12):1025-30
references: 11702068
references: Proc Natl Acad Sci U S A. 1997 Apr 1;94(7):3229-34
references: 9096375
references: Nature. 1990 Oct 25;347(6295):776-80
references: 2234050
references: Protein Sci. 2010 Oct;19(10):1978-84
references: 20669149
references: FEBS J. 2006 Jul;273(14):3172-82
references: 16774643
references: Biochemistry. 2012 Jun 26;51(25):5105-12
references: 22670769
references: Nature. 1998 Aug 6;394(6693):595-9
references: 9707123
references: J Am Chem Soc. 2012 Sep 19;134(37):15343-50
references: 22916679
references: Curr Biol. 2005 Sep 20;15(18):1684-9
references: 16169492
references: FEBS J. 2012 Aug;279(16):2892-904
references: 22715935
references: Hum Mol Genet. 2000 Jul 22;9(12):1779-86
references: 10915766
references: Trends Biochem Sci. 1993 Aug;18(8):301-6
references: 8236445
references: J Mol Biol. 2003 May 16;328(5):1137-47
references: 12729747
references: Philos Trans R Soc Lond B Biol Sci. 2011 Apr 27;366(1568):1250-64
references: 21402584
references: PLoS One. 2012;7(8):e43723
references: 22952748
references: Mol Vis. 2002 Jun 15;8:171-84
references: 12107413
references: Nature. 2006 Feb 23;439(7079):965-8
references: 16495997
references: J Biol Chem. 1998 Nov 13;273(46):30669-74
references: 9804840
references: Nature. 1983 Mar 31-Apr 6;302(5907):415-7
references: 6835373
references: Prog Retin Eye Res. 2012 Jul;31(4):332-49
references: 22465790
references: Proc Natl Acad Sci U S A. 1992 Nov 1;89(21):10449-53
references: 1438232
references: Int J Biochem Cell Biol. 2012 Oct;44(10):1593-612
references: 22750029
references: Mol Vis. 1998 Apr 30;4:8
references: 9565648
references: Chem Biol. 2012 May 25;19(5):599-607
references: 22633411
references: Dev Growth Differ. 1992 Jun;34(3):277-283
references: 37280883
references: Exp Eye Res. 2003 Oct;77(4):409-22
references: 12957141
references: Biochemistry. 2009 Mar 31;48(12):2597-609
references: 19216553
references: Proc Biol Sci. 1997 Jul 22;264(1384):1077-84
references: 9263473
references: Neuromuscul Disord. 2012 Jan;22(1):66-72
references: 21920752
references: J Mol Biol. 1999 Mar 12;286(5):1533-45
references: 10064714
references: Exp Eye Res. 1995 Nov;61(5):637-9
references: 8654507
references: Nature. 1985 Jun 27-Jul 3;315(6022):771-3
references: 3925350
references: J Mol Biol. 2009 Feb 6;385(5):1481-97
references: 19041879
references: Hum Genomics. 2012 Dec 01;6:26
references: 23199295
references: Protein Sci. 1998 Jun;7(6):1280-5
references: 9655330
references: Biochemistry. 2009 May 5;48(17):3708-16
references: 19358562
references: J Mol Biol. 2008 Sep 5;381(3):509-18
references: 18582473
references: Exp Eye Res. 1992 Apr;54(4):573-81
references: 1623942
references: Int J Biochem Cell Biol. 2012 Oct;44(10):1687-97
references: 22405853
references: EMBO J. 2012 Dec 12;31(24):4587-94
references: 23188086
references: Structure. 2006 Dec;14(12):1823-34
references: 17161372
references: J Mol Biol. 2011 Oct 21;413(2):310-20
references: 21839749
references: Proc Natl Acad Sci U S A. 2011 Apr 19;108(16):6409-14
references: 21464278
references: Trends Biochem Sci. 2012 Mar;37(3):106-17
references: 22177323
references: Int J Dev Biol. 2004;48(8-9):829-44
references: 15558475
references: J Mol Biol. 2007 Sep 7;372(1):205-22
references: 17659303
references: Chem Rev. 2011 Dec 14;111(12):7710-48
references: 21919528
references: Invest Ophthalmol Vis Sci. 1997 Sep;38(10):1911-21
references: 9331254
references: J Mol Biol. 2007 Sep 21;372(3):774-97
references: 17681537
references: Nat Struct Mol Biol. 2010 Sep;17(9):1037-42
references: 20802487
references: J Mol Evol. 2010 Sep;71(3):219-30
references: 20725717
references: J Mol Biol. 2009 Oct 9;392(5):1242-52
references: 19646995
references: J Comp Neurol. 2008 Jul 1;509(1):88-102
references: 18421706
references: J Exp Biol. 2008 May;211(Pt 10):1559-64
references: 18456882
references: Structure. 2001 Feb 7;9(2):115-24
references: 11250196
references: Proc Natl Acad Sci U S A. 2001 Jun 19;98(13):7534-9
references: 11416222
references: Protein Sci. 2010 May;19(5):1031-43
references: 20440841
references: Proc Natl Acad Sci U S A. 2011 Dec 20;108(51):20491-6
references: 22143763
references: FEBS J. 2006 Feb;273(3):481-90
references: 16420472
references: Vet Parasitol. 2010 Apr 19;169(1-2):62-75
references: 20089359
references: J Mol Biol. 2011 Aug 5;411(1):110-22
references: 21641913
references: FEBS J. 2005 May;272(9):2276-91
references: 15853812
references: Protein Sci. 2003 Nov;12(11):2606-12
references: 14573871
references: Proc Natl Acad Sci U S A. 2010 Feb 02;107(5):2007-12
references: 20133845
references: J Mol Biol. 2005 Oct 14;353(1):68-79
references: 16165157
references: Prog Retin Eye Res. 2007 Jan;26(1):78-98
references: 17166758
references: Nat Struct Mol Biol. 2005 Oct;12(10):842-6
references: 16205709
references: Science. 2004 Oct 29;306(5697):869-71
references: 15514158
references: Proc Natl Acad Sci U S A. 2009 Aug 11;106(32):13272-7
references: 19651604
references: J Mol Histol. 2011 Feb;42(1):59-69
references: 21203897
references: Protein Sci. 2007 Apr;16(4):615-25
references: 17327390
references: Photochem Photobiol. 2006 Jul-Aug;82(4):1088-96
references: 16602829
references: J Mol Biol. 2004 Oct 15;343(2):435-44
references: 15451671
references: J Biol Chem. 1997 Jan 24;272(4):2268-75
references: 8999933
references: Structure. 2011 Dec 7;19(12):1855-63
references: 22153508
references: Top Curr Chem. 2013;328:69-98
references: 22576357
references: Proc Natl Acad Sci U S A. 1991 Jul 1;88(13):5660-4
references: 2062844
references: Structure. 2005 Aug;13(8):1165-71
references: 16084388
references: J Mol Biol. 1998 Mar 20;277(1):27-35
references: 9514758
references: Nature. 1981 Feb 26;289(5800):771-7
references: 7464942
references: Biochemistry. 2009 May 12;48(18):3828-37
references: 19323523
references: Cell Stress Chaperones. 2003 Spring;8(1):53-61
references: 12820654
references: Proc Natl Acad Sci U S A. 2012 Sep 18;109(38):15383-8
references: 22949670
references: J Mol Evol. 1990 Feb;30(2):140-5
references: 2107329
references: Biochemistry. 2009 Dec 29;48(51):12180-90
references: 19921810
references: J Mol Biol. 2011 Aug 19;411(3):680-99
references: 21684289
references: Protein Sci. 1997 Aug;6(8):1612-20
references: 9260274
references: Prog Biophys Mol Biol. 2004 Nov;86(3):407-85
references: 15302206
references: PLoS One. 2008 Mar 12;3(3):e1770
references: 18335045
references: Exp Eye Res. 1997 Nov;65(5):609-30
references: 9367641
references: J Mol Biol. 2011 Apr 22;408(1):118-34
references: 21329698