Functional surfaces on the actin-binding protein coronin revealed by systematic mutagenesis.
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.
Gandhi
Meghal
M
Department of Biology, Rosenstiel Basic Medical Science Research Center, Brandeis University, Waltham, Massachusetts 02454, USA.
Jangi
Mohini
M
Goode
Bruce L
BL
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*
D000199:Actins; D051345:Destrin; D008840:Microfilament Proteins; C072061:coronin proteins
Biol Pharm Bull. 2003 Apr;26(4):409-16
12673016
Biochem J. 2005 Apr 15;387(Pt 2):325-31
15601263
Mol Cell. 2009 May 15;34(3):364-74
19450534
EMBO J. 1991 Dec;10(13):4097-104
1661669
Subcell Biochem. 2008;48:20-30
18925368
EMBO J. 1997 Sep 15;16(18):5520-30
9312011
Genetics. 1992 Oct;132(2):337-50
1427032
Annu Rev Biophys. 2010;39:449-70
20192778
Mol Biol Cell. 2010 Aug 15;21(16):2894-904
20587778
Biochemistry. 1984 Dec 18;23(26):6631-41
6543322
J Biol Chem. 1971 Aug 10;246(15):4866-71
4254541
Science. 2006 Aug 11;313(5788):839-42
16902139
Cell. 2007 Mar 9;128(5):915-29
17350576
J Cell Biol. 2002 Dec 23;159(6):993-1004
12499356
Trends Cell Biol. 2010 Apr;20(4):187-95
20133134
J Cell Biol. 1999 Jan 11;144(1):83-98
9885246
J Cell Biol. 2006 Oct 23;175(2):315-24
17060499
J Biol Chem. 2002 Dec 13;277(50):48858-67
12377779
J Cell Biol. 2008 Jul 28;182(2):341-53
18663144
Cell. 1995 Dec 15;83(6):915-24
8521515
Nat Struct Mol Biol. 2005 Jan;12(1):26-31
15592479
Mol Biol Cell. 2005 Jun;16(6):2786-98
15800061
Nature. 1997 Jul 3;388(6637):78-82
9214506
J Mol Biol. 2008 Feb 22;376(3):607-13
18177666
J Cell Sci. 1999 Sep;112 (Pt 17):2833-42
10444378
Curr Biol. 1998 Nov 19;8(23):1281-4
9822583
Structure. 2006 Jan;14(1):87-96
16407068
Dev Cell. 2009 Sep;17(3):310-22
19758556
J Cell Sci. 2010 Apr 15;123(Pt 8):1329-42
20332110
J Cell Sci. 2007 May 15;120(Pt 10):1779-90
17456547
Methods Enzymol. 2002;351:433-41
12073361
J Cell Biol. 2009 Jun 15;185(6):1097-110
19506040
J Cell Biol. 1993 Jan;120(1):163-73
8380174