The Dictyostelium type V myosin MyoJ is responsible for the cortical association and motility of contractile vacuole membranes.
The contractile vacuole (CV) complex in Dictyostelium is a tubulovesicular osmoregulatory organelle that exhibits extensive motility along the actin-rich cortex, providing a useful model for investigating myosin-dependent membrane transport. Here, we show that the type V myosin myoJ localizes to CV membranes and is required for efficient osmoregulation, the normal accumulation of CV membranes in the cortex, and the conversion of collapsed bladder membranes into outwardly radiating cortical CV tubules. Complementation of myoJ-null cells with a version of myoJ containing a shorter lever arm causes these radiating tubules to move at a slower speed, confirming myoJ's role in translocating CV membranes along the cortex. MyoJ-null cells also exhibit a dramatic concentration of CV membranes around the microtubule-organizing center. Consistently, we demonstrate that CV membranes also move bi-directionally on microtubules between the cortex and the centrosome. Therefore, myoJ cooperates with plus and minus end-directed microtubule motors to drive the normal distribution and dynamics of the CV complex in Dictyostelium.
Jung
Goeh
G
Laboratory of Cell Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Titus
Margaret A
MA
Hammer
John A
JA
D000818:Animals; D003572:Cytochalasins / Q000378:metabolism; D004023:Dictyostelium / Q000166:cytology / Q000378:metabolism; D005816:Genetic Complementation Test; D007425:Intracellular Membranes / Q000378:metabolism*; D022101:Microtubule-Organizing Center / Q000378:metabolism; D024701:Myosin Type V / Q000378:metabolism*; D015739:Nocodazole; D010641:Phenotype; D015800:Protozoan Proteins / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D014404:Tubulin / Q000235:genetics / Q000378:metabolism; D050257:Tubulin Modulators / Q000378:metabolism; D014617:Vacuoles / Q000378:metabolism*; D014867:Water / Q000378:metabolism; D014882:Water-Electrolyte Balance / Q000502:physiology
D003572:Cytochalasins; D015800:Protozoan Proteins; D011993:Recombinant Fusion Proteins; D014404:Tubulin; D050257:Tubulin Modulators; D014867:Water; D024701:Myosin Type V; D015739:Nocodazole
Biochemistry. 2002 Jul 2;41(26):8508-17
12081502
J Cell Sci. 1999 Nov;112 ( Pt 22):3995-4005
10547360
Nature. 1993 Oct 28;365(6449):841-3
8413668
J Cell Biol. 1993 Jun;121(6):1311-27
8509452
J Biol Chem. 1996 Mar 22;271(12):7120-7
8636147
J Cell Biol. 1992 Jul;118(2):347-58
1629238
Eur J Cell Biol. 2006 Sep;85(9-10):859-71
16831485
Proc Natl Acad Sci U S A. 2007 Mar 13;104(11):4332-6
17360524
J Cell Sci. 2008 Apr 1;121(Pt 7):1054-64
18334553
Plasmid. 2000 Nov;44(3):231-8
11078649
J Cell Biol. 2001 Jun 25;153(7):1479-97
11425877
J Muscle Res Cell Motil. 1996 Aug;17(4):411-24
8884597
Cell Biol Int. 2002;26(10):845-52
12421575
Curr Biol. 2004 Jan 6;14(1):1-10
14711408
FEBS Lett. 2004 Nov 5;577(1-2):227-32
15527790
J Cell Sci. 2002 Jul 15;115(Pt 14):2893-905
12082150
J Cell Biol. 2002 Jan 7;156(1):35-9
11781333
J Biol Chem. 2002 Apr 5;277(14):12432-6
11856727
J Biol Chem. 2008 Oct 3;283(40):26902-10
18650439
J Cell Sci. 1996 May;109 ( Pt 5):1041-51
8743951
J Biol Chem. 2002 Jul 12;277(28):25423-30
11980908
Curr Opin Cell Biol. 2006 Feb;18(1):68-73
16378722
J Cell Biol. 1996 Apr;133(2):305-23
8609164
BMC Genomics. 2006 Jul 20;7:183
16857047
J Cell Sci. 1993 Dec;106 ( Pt 4):1103-13
8126094
Trends Cell Biol. 2009 Jun;19(6):245-52
19406643
J Cell Biol. 1998 Dec 28;143(7):1899-918
9864363
Nat Cell Biol. 2002 Apr;4(4):271-8
11887186