Loss of myosin VI reduces secretion and the size of the Golgi in fibroblasts from Snell's waltzer mice.
Golgi morphology and function are dependent on an intact microtubule and actin cytoskeleton. Myosin VI, an unusual actin-based motor protein moving towards the minus ends of actin filaments, has been localized to the Golgi complex at the light and electron microscopic level. Myosin VI is present in purified Golgi membranes as a peripheral membrane protein, targeted by its globular tail domain. To investigate the function of myosin VI at the Golgi complex, immortal fibroblastic cell lines of Snell's waltzer mice lacking myosin VI were established. In these cell lines, where myosin VI is absent, the Golgi complex is reduced in size by approximately 40% compared with wild-type cells. Furthermore, protein secretion of a reporter protein from Snell's waltzer cells is also reduced by 40% compared with wild-type cells. Rescue experiments showed that fully functional myosin VI was able to restore Golgi complex morphology and protein secretion in Snell's waltzer cells to the same level as that observed in wild-type cells.
Warner
Claire L
CL
MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK.
Stewart
Abigail
A
Luzio
J Paul
JP
Steel
Karen P
KP
Libby
Richard T
RT
Kendrick-Jones
John
J
Buss
Folma
F
D000818:Animals; D000906:Antibodies / Q000378:metabolism; D002460:Cell Line; D002645:Chickens; D022162:Cytoplasmic Vesicles / Q000737:chemistry / Q000378:metabolism; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism* / Q000648:ultrastructure; D007150:Immunohistochemistry; D007425:Intracellular Membranes / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008815:Mice, Inbred Strains; D018995:Myosin Heavy Chains / Q000235:genetics / Q000378:metabolism*; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014162:Transfection; D021601:trans-Golgi Network / Q000378:metabolism
D000906:Antibodies; D008565:Membrane Proteins; D011993:Recombinant Fusion Proteins; C089785:myosin VI; D018995:Myosin Heavy Chains