Yeast homologues of lethal giant larvae and type V myosin cooperate in the regulation of Rab-dependent vesicle clustering and polarized exocytosis.
Lgl family members play an important role in the regulation of cell polarity in eukaryotic cells. The yeast homologues Sro7 and Sro77 are thought to act downstream of the Rab GTPase Sec4 to promote soluble N-ethylmaleimide-sensitive factor adaptor protein receptor (SNARE) function in post-Golgi transport. In this article, we characterize the interaction between Sro7 and the type V myosin Myo2 and show that this interaction is important for two distinct aspects of Sro7 function. First, we show that this interaction plays a positive role in promoting the polarized localization of Sro7 to sites of active growth. Second, we find evidence that Myo2 negatively regulates Sro7 function in vesicle clustering. Mutants in either Myo2 or Sro7 that are defective for this interaction show hypersensitivity to Sro7 overexpression, which results in Sec4-dependent accumulation of large groups of vesicles in the cytoplasm. This suggests that Myo2 serves a dual function, to both recruit Sro7 to secretory vesicles and inhibit its Rab-dependent tethering activity until vesicles reach the plasma membrane. Thus Sro7 appears to coordinate the spatial and temporal nature of both Rab-dependent tethering and SNARE-dependent membrane fusion of exocytic vesicles with the plasma membrane.
Department of Cell and Developmental Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7090, USA.
Guendalina
G
Rossi
Patrick
P
Brennwald
D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D016764:Cell Polarity; D005089:Exocytosis / Q000502:physiology*; D006056:Golgi Apparatus / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D018995:Myosin Heavy Chains / Q000235:genetics / Q000378:metabolism*; D024701:Myosin Type V / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D050600:SNARE Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D022142:Secretory Vesicles / Q000378:metabolism*; D016415:Sequence Alignment; D033921:Vesicular Transport Proteins / Q000235:genetics / Q000378:metabolism; D020691:rab GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*
D048868:Adaptor Proteins, Signal Transducing; C077512:MYO2 protein, S cerevisiae; D011993:Recombinant Fusion Proteins; C060862:SEC15 protein, S cerevisiae; D050600:SNARE Proteins; C116430:SRO7 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins; D024701:Myosin Type V; D018995:Myosin Heavy Chains; D020691:rab GTP-Binding Proteins
J Cell Biol. 2006 Jan 2;172(1):55-66
16390997
J Cell Biol. 1991 May;113(3):539-51
2016335
Mol Biol Cell. 2009 Dec;20(24):5276-89
19828734
J Cell Biol. 2000 Apr 3;149(1):95-110
10747090
Sci STKE. 2001 Sep 18;2001(100):re11
11579231
J Cell Biol. 2001 Nov 12;155(4):581-92
11706050
Traffic. 2010 May;11(5):637-50
20149155
Cell. 2003 Feb 21;112(4):467-80
12600311
Cell. 1994 Oct 21;79(2):245-58
7954793
Cell. 1988 Jun 3;53(5):753-68
3131018
J Cell Biol. 2004 Dec 6;167(5):889-901
15583031
Nature. 2000 Nov 30;408(6812):596-600
11117748
Nature. 2007 Mar 29;446(7135):567-71
17392788
Physiology (Bethesda). 2005 Aug;20:239-51
16024512
J Cell Biol. 1989 Sep;109(3):1023-36
2504727
Mol Biol Cell. 2000 Feb;11(2):691-702
10679024
J Biol Chem. 1998 Dec 11;273(50):33610-8
9837945
Mol Biol Cell. 2010 Aug 1;21(15):2746-55
20534812
FEBS Lett. 2002 Feb 20;513(1):107-13
11911888
Proc Natl Acad Sci U S A. 2006 Aug 8;103(32):11821-7
16882731
Mol Biol Cell. 2004 Mar;15(3):1436-44
14718573
J Biol Chem. 2003 Feb 7;278(6):4347-52
12446675
J Cell Biol. 2002 Jun 10;157(6):1005-15
12045183
EMBO J. 1996 Dec 2;15(23):6483-94
8978675
J Cell Biol. 1997 Jun 30;137(7):1495-509
9199166
Nature. 2009 Jun 25;459(7250):1091-7
19458617
J Biol Chem. 1997 Jun 27;272(26):16610-7
9195974
J Cell Biol. 2002 Jan 7;156(1):35-9
11781333
Curr Biol. 2004 Jan 6;14(1):R33-4
14711434
J Cell Biol. 1999 Nov 15;147(4):791-808
10562281
Proc Natl Acad Sci U S A. 1998 Dec 8;95(25):14799-804
9843969
Mol Biol Cell. 2008 Oct;19(10):4177-87
18653471
J Cell Biol. 2005 Aug 15;170(4):583-94
16103227
J Cell Biol. 1998 Aug 10;142(3):711-22
9700160
J Cell Biol. 1995 Mar;128(6):1055-68
7896871
EMBO J. 1999 Feb 15;18(4):1071-80
10022848
J Cell Biol. 1998 Dec 28;143(7):1931-45
9864365
Mol Biol Cell. 1999 Dec;10(12):4121-33
10588647
Genetics. 1998 Aug;149(4):1717-27
9691031
Nat Cell Biol. 1999 May;1(1):E17-22
10559876
Curr Biol. 2005 Jun 21;15(12):1136-42
15964280
J Cell Biol. 2005 Jul 18;170(2):273-83
16027223
J Cell Biol. 1999 Jul 12;146(1):125-40
10402465
Nature. 1993 Apr 8;362(6420):560-3
8464498