Role of myosin-II phosphorylation in V12Cdc42-mediated disruption of Drosophila cellularization.

Journal Article (Journal Article)

Microinjection of constitutively active Cdc42 (V12Cdc42) disrupts the actomyosin cytoskeleton during cellularization (Crawford et al., Dev. Biol., 204, 151-164 (1998)). The p21-activated kinase (PAK) family of Ser/Thr kinases are effectors of GTP-bound forms of the small GTPases, Cdc42 and Rac. Drosophila PAK, which colocalizes with actin and myosin-II during cellularization, concentrates at sites of V12Cdc42-induced actomyosin disruption. In vitro biochemical analyses demonstrate that PAK phosphorylates the regulatory light chain (RLC) of Drosophila nonmuscle myosin-II on Ser21, a site known to activate myosin-II function. Although activated PAK does not disrupt the actomyosin cytoskeleton, it induces increased levels of Ser21 phosphorylated RLC. These findings suggest that increased levels of RLC phosphorylation do not contribute to disruption of the actomyosin hexagonal array.

Full Text

Duke Authors

Cited Authors

  • Crawford, JM; Su, Z; Varlamova, O; Bresnick, AR; Kiehart, DP

Published Date

  • March 2001

Published In

Volume / Issue

  • 80 / 3

Start / End Page

  • 240 - 244

PubMed ID

  • 11322388

Electronic International Standard Serial Number (EISSN)

  • 1618-1298

International Standard Serial Number (ISSN)

  • 0171-9335

Digital Object Identifier (DOI)

  • 10.1078/0171-9335-00156


  • eng