title: Microtubules as platforms for assaying actin polymerization in vivo.
abstract: The actin cytoskeleton is continuously remodeled through cycles of actin filament assembly and disassembly. Filaments are born through nucleation and shaped into supramolecular structures with various essential functions. These range from contractile and protrusive assemblies in muscle and non-muscle cells to actin filament comets propelling vesicles or pathogens through the cytosol. Although nucleation has been extensively studied using purified proteins in vitro, dissection of the process in cells is complicated by the abundance and molecular complexity of actin filament arrays. We here describe the ectopic nucleation of actin filaments on the surface of microtubules, free of endogenous actin and interfering membrane or lipid. All major mechanisms of actin filament nucleation were recapitulated, including filament assembly induced by Arp2/3 complex, formin and Spir. This novel approach allows systematic dissection of actin nucleation in the cytosol of live cells, its genetic re-engineering as well as screening for new modifiers of the process.
authors: Helmholtz Centre for Infection Research, Braunschweig, Germany.
authors: J Margit
authors: JM
authors: Oelkers
authors: Marlene
authors: M
authors: Vinzenz
authors: Maria
authors: M
authors: Nemethova
authors: Sonja
authors: S
authors: Jacob
authors: Frank P L
authors: FP
authors: Lai
authors: Jennifer
authors: J
authors: Block
authors: Malgorzata
authors: M
authors: Szczodrak
authors: Eugen
authors: E
authors: Kerkhoff
authors: Steffen
authors: S
authors: Backert
authors: Kai
authors: K
authors: Schlüter
authors: Theresia E B
authors: TE
authors: Stradal
authors: J Victor
authors: JV
authors: Small
authors: Stefan A
authors: SA
authors: Koestler
authors: Klemens
authors: K
authors: Rottner
references: EMBO J. 2002 Nov 15;21(22):6083-94
references: 12426380
references: Cell. 1999 Apr 16;97(2):221-31
references: 10219243
references: EMBO Rep. 2001 Sep;2(9):850-7
references: 11559594
references: J Biol Chem. 1991 May 25;266(15):9841-6
references: 2033072
references: Proc Natl Acad Sci U S A. 2007 Jul 17;104(29):11933-8
references: 17606906
references: EMBO J. 1994 Feb 15;13(4):758-63
references: 8112291
references: J Cell Biol. 2010 Jun 28;189(7):1087-96
references: 20566685
references: Nature. 2005 Jan 27;433(7024):382-8
references: 15674283
references: Trends Cell Biol. 2002 Mar;12(3):112-20
references: 11859023
references: Curr Opin Cell Biol. 2004 Oct;16(5):590-6
references: 15363811
references: Curr Opin Cell Biol. 2007 Oct;19(5):529-33
references: 17923403
references: Cell Motil Cytoskeleton. 2003 Jan;54(1):81-90
references: 12451597
references: Trends Cell Biol. 2010 Nov;20(11):650-61
references: 20888769
references: Science. 2008 Apr 11;320(5873):239-43
references: 18403713
references: Methods Cell Biol. 2008;88:257-72
references: 18617038
references: J Biol Chem. 2001 Sep 21;276(38):35761-7
references: 11459849
references: Genesis. 2009 Sep;47(9):638-46
references: 19621352
references: Nat Rev Mol Cell Biol. 2006 Oct;7(10):713-26
references: 16990851
references: J Mol Biol. 1976 Nov;108(1):139-50
references: 1003481
references: Mol Biol Cell. 2009 Jul;20(14):3209-23
references: 19458196
references: Trends Cell Biol. 2008 Oct;18(10):494-504
references: 18774717
references: Nat Cell Biol. 2001 Jan;3(1):76-82
references: 11146629
references: Science. 2001 May 25;292(5521):1502-6
references: 11379633
references: FEBS Lett. 2002 Feb 20;513(1):98-106
references: 11911887
references: EMBO J. 2008 Apr 9;27(7):982-92
references: 18309290
references: Science. 2009 Sep 4;325(5945):1250-4
references: 19729655
references: J Cell Sci. 2000 Dec;113 Pt 24:4421-6
references: 11082035
references: Cell. 2007 Oct 19;131(2):337-50
references: 17956734
references: Curr Opin Cell Biol. 2006 Feb;18(1):4-10
references: 16343889
references: Curr Biol. 2002 Jun 25;12(12):1034-9
references: 12123579
references: Cell Mol Life Sci. 2008 Sep;65(17):2688-701
references: 18488141
references: J Cell Biol. 2010 Mar 22;188(6):769-77
references: 20231387
references: Biochim Biophys Acta. 2010 Feb;1803(2):152-63
references: 20102729
references: Nat Cell Biol. 2008 Mar;10(3):306-13
references: 18278037
references: Cell. 2006 Jun 30;125(7):1241-52
references: 16814712
references: J Biol Chem. 2006 Apr 14;281(15):10589-97
references: 16403731
references: Nat Rev Neurosci. 2008 May;9(5):344-56
references: 18425089
references: Mol Cell Biol. 2003 Mar;23(6):2162-70
references: 12612086
references: Eur J Cell Biol. 2009 Jul;88(7):385-96
references: 19324455
references: Mol Cell. 2007 Nov 30;28(4):555-68
references: 18042452
references: Nat Cell Biol. 2001 Aug;3(8):699-707
references: 11483954
references: Curr Biol. 1998 Dec 17-31;8(25):1347-56
references: 9889097
references: EMBO J. 2004 Feb 25;23(4):749-59
references: 14765121
references: Trends Cell Biol. 2004 Jun;14(6):303-11
references: 15183187
references: Nat Cell Biol. 2010 May;12(5):429-35
references: 20418872
references: Mol Biol Cell. 2006 Jun;17(6):2581-91
references: 16597702
references: Nat Cell Biol. 2001 Mar;3(3):259-66
references: 11231575
references: Curr Opin Cell Biol. 2009 Feb;21(1):28-37
references: 19168341
references: Mol Cell. 2008 Nov 7;32(3):426-38
references: 18995840
references: J Cell Biol. 2008 Mar 24;180(6):1233-44
references: 18362182
references: J Cell Biol. 2000 Aug 21;150(4):807-22
references: 10953005
references: Dev Cell. 2009 Sep;17(3):310-22
references: 19758556
references: J Cell Biol. 2006 Sep 11;174(6):863-75
references: 16966425
references: Nat Rev Mol Cell Biol. 2010 Jan;11(1):62-74
references: 19997130
references: Biochemistry. 2007 May 22;46(20):5904-10
references: 17444659
references: Eur J Cell Biol. 2011 Nov;90(11):922-5
references: 21129813
references: J Cell Sci. 2009 Sep 1;122(Pt 17):3037-49
references: 19692590
references: Cell. 2007 Mar 9;128(5):901-13
references: 17350575
references: Biophys J. 2008 Jun;94(12):4890-905
references: 18326652
references: Nat Rev Mol Cell Biol. 2010 Apr;11(4):237-51
references: 20237478
references: Science. 2010 Dec 10;330(6010):1536-40
references: 21148390
references: J Cell Biol. 1985 Aug;101(2):597-602
references: 4040521
references: Cell Microbiol. 2003 Jun;5(6):385-93
references: 12780776
references: J Microsc. 2008 Sep;231(3):506-17
references: 18755006
references: Curr Biol. 2003 Oct 14;13(20):1814-9
references: 14561408
references: Cell Motil Cytoskeleton. 2008 Sep;65(9):687-707
references: 18615630
references: J Cell Biol. 2007 Oct 8;179(1):117-28
references: 17923532