Targeting of the myosin-I myr 3 to intercellular adherens type junctions induced by dominant active Cdc42 in HeLa cells.
Myr 3, a member of the myosin-I family from rat, is shown in this study to be localized at adherens-type intercellular junctions in epithelial and nonepithelial tissues. Formation of intercellular junctions and the accompanying recruitment of myr 3 to these junctions involves signaling by the Rho subfamily of small GTP-binding proteins. This conclusion is based on studies with HtTA-1 HeLa cells that were induced by overexpression of constitutively active Cdc42Hs to form typical adherens-type intercellular junctions enriched in cadherins (N-cadherin), beta-catenin, filamentous actin and myr 3. Recruitement of myr 3 to Cdc42-induced adherens junctions in HeLa cells was dependent on a short region of the tail domain and a functional myosin motor domain, but was independent of its myosin-I tail homology and SH3 regions. Overexpression of constitutively active Rac1 induced a distinct type of adherens junction in HeLa cells that was characterized by elaborate intercellular interdigitations enriched in N-cadherin, beta-catenin and F-actin. Myr 3 was often present, but not specifically enriched in the intercellular junctions induced by constitutively active Rac1.
Stöffler
H E
HE
Adolf-Butenandt-Institute, Cell Biology, Ludwig-Maximilians-University, D-80336 Munich, Germany.
Honnert
U
U
Bauer
C A
CA
Höfer
D
D
Schwarz
H
H
Müller
R T
RT
Drenckhahn
D
D
Bähler
M
M
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D006367:HeLa Cells; D006801:Humans; D007365:Intercellular Junctions / Q000378:metabolism* / Q000648:ultrastructure; D008854:Microscopy, Electron; D020409:Molecular Motor Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D024461:Myosin Type I; D009218:Myosins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D051381:Rats; D014162:Transfection; D020764:cdc42 GTP-Binding Protein; D020744:rac GTP-Binding Proteins
D018797:Cell Cycle Proteins; D020409:Molecular Motor Proteins; C503808:Myo1e protein, rat; D019204:GTP-Binding Proteins; D024461:Myosin Type I; D009218:Myosins; D020764:cdc42 GTP-Binding Protein; D020744:rac GTP-Binding Proteins