title: Functional surfaces on the actin-binding protein coronin revealed by systematic mutagenesis.
abstract: Coronin is a conserved actin-binding protein that co-functions with ADF/cofilin and Arp2/3 complex to govern cellular actin dynamics. Despite emerging roles for coronin in a range of physiological processes and disease states, a detailed understanding of the molecular interactions of coronin with actin and other binding partners has been lacking. Here, we performed a systematic mutational analysis of surfaces on the yeast coronin β-propeller domain, which binds to F-actin and is conserved in all coronin family members. We generated 21 mutant alleles and analyzed their biochemical effects on actin binding and ADF/cofilin activity. Conserved actin-binding residues mapped to a discrete ridge stretching across one side of the β-propeller. Mutants defective in actin binding showed loss of synergy with ADF/cofilin in severing filaments, diminished localization to actin structures in vivo, and loss of coronin overexpression growth defects. In addition, one allele showed normal actin binding but impaired functional interactions with ADF/cofilin. Another allele showed normal actin binding but failed to cause coronin overexpression defects. Together, these results indicate that actin binding is critical for many of the biochemical and cellular functions of coronin and that the β-propeller domain mediates additional functional interactions with ADF/cofilin and possibly other ligands. Conservation of the actin-binding surfaces across distant species and in all three major classes of coronin isoforms suggests that the nature of the coronin-actin association may be similar in other family members.
authors.affiliation: Department of Biology, Rosenstiel Basic Medical Science Research Center, Brandeis University, Waltham, Massachusetts 02454, USA.
authors.forename: Meghal
authors.initials: M
authors.lastname: Gandhi
authors.forename: Mohini
authors.initials: M
authors.lastname: Jangi
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Goode
mesh_terms: D000199:Actins / Q000235:genetics / Q000378:metabolism*; D000483:Alleles; D051345:Destrin / Q000276:immunology / Q000378:metabolism; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism*; D016296:Mutagenesis; D010449:Peptide Mapping / Q000379:methods; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*
chemical_list: D000199:Actins; D051345:Destrin; D008840:Microfilament Proteins; C072061:coronin proteins
references.citation: Biol Pharm Bull. 2003 Apr;26(4):409-16
references.pmid: 12673016
references.citation: Biochem J. 2005 Apr 15;387(Pt 2):325-31
references.pmid: 15601263
references.citation: Mol Cell. 2009 May 15;34(3):364-74
references.pmid: 19450534
references.citation: EMBO J. 1991 Dec;10(13):4097-104
references.pmid: 1661669
references.citation: Subcell Biochem. 2008;48:20-30
references.pmid: 18925368
references.citation: EMBO J. 1997 Sep 15;16(18):5520-30
references.pmid: 9312011
references.citation: Genetics. 1992 Oct;132(2):337-50
references.pmid: 1427032
references.citation: Annu Rev Biophys. 2010;39:449-70
references.pmid: 20192778
references.citation: Mol Biol Cell. 2010 Aug 15;21(16):2894-904
references.pmid: 20587778
references.citation: Biochemistry. 1984 Dec 18;23(26):6631-41
references.pmid: 6543322
references.citation: J Biol Chem. 1971 Aug 10;246(15):4866-71
references.pmid: 4254541
references.citation: Science. 2006 Aug 11;313(5788):839-42
references.pmid: 16902139
references.citation: Cell. 2007 Mar 9;128(5):915-29
references.pmid: 17350576
references.citation: J Cell Biol. 2002 Dec 23;159(6):993-1004
references.pmid: 12499356
references.citation: Trends Cell Biol. 2010 Apr;20(4):187-95
references.pmid: 20133134
references.citation: J Cell Biol. 1999 Jan 11;144(1):83-98
references.pmid: 9885246
references.citation: J Cell Biol. 2006 Oct 23;175(2):315-24
references.pmid: 17060499
references.citation: J Biol Chem. 2002 Dec 13;277(50):48858-67
references.pmid: 12377779
references.citation: J Cell Biol. 2008 Jul 28;182(2):341-53
references.pmid: 18663144
references.citation: Cell. 1995 Dec 15;83(6):915-24
references.pmid: 8521515
references.citation: Nat Struct Mol Biol. 2005 Jan;12(1):26-31
references.pmid: 15592479
references.citation: Mol Biol Cell. 2005 Jun;16(6):2786-98
references.pmid: 15800061
references.citation: Nature. 1997 Jul 3;388(6637):78-82
references.pmid: 9214506
references.citation: J Mol Biol. 2008 Feb 22;376(3):607-13
references.pmid: 18177666
references.citation: J Cell Sci. 1999 Sep;112 (Pt 17):2833-42
references.pmid: 10444378
references.citation: Curr Biol. 1998 Nov 19;8(23):1281-4
references.pmid: 9822583
references.citation: Structure. 2006 Jan;14(1):87-96
references.pmid: 16407068
references.citation: Dev Cell. 2009 Sep;17(3):310-22
references.pmid: 19758556
references.citation: J Cell Sci. 2010 Apr 15;123(Pt 8):1329-42
references.pmid: 20332110
references.citation: J Cell Sci. 2007 May 15;120(Pt 10):1779-90
references.pmid: 17456547
references.citation: Methods Enzymol. 2002;351:433-41
references.pmid: 12073361
references.citation: J Cell Biol. 2009 Jun 15;185(6):1097-110
references.pmid: 19506040
references.citation: J Cell Biol. 1993 Jan;120(1):163-73
references.pmid: 8380174