p116Rip targets myosin phosphatase to the actin cytoskeleton and is essential for RhoA/ROCK-regulated neuritogenesis

Jacqueline Mulder; Aafke Ariaens; Dick van den Boomen; Wouter H Moolenaar

doi:10.1091/mbc.e04-04-0275

p116Rip targets myosin phosphatase to the actin cytoskeleton and is essential for RhoA/ROCK-regulated neuritogenesis

Mol Biol Cell. 2004 Dec;15(12):5516-27. doi: 10.1091/mbc.e04-04-0275. Epub 2004 Oct 6.

Authors

Jacqueline Mulder¹, Aafke Ariaens, Dick van den Boomen, Wouter H Moolenaar

Affiliation

¹ Division of Cellular Biochemistry and Centre for Biomedical Genetics, The Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands.

Abstract

Activation of the RhoA-Rho kinase (ROCK) pathway stimulates actomyosin-driven contractility in many cell systems, largely through ROCK-mediated inhibition of myosin II light chain phosphatase. In neuronal cells, the RhoA-ROCK-actomyosin pathway signals cell rounding, growth cone collapse, and neurite retraction; conversely, inhibition of RhoA/ROCK promotes cell spreading and neurite outgrowth. The actin-binding protein p116(Rip), whose N-terminal region bundles F-actin in vitro, has been implicated in Rho-dependent neurite remodeling; however, its function is largely unknown. Here, we show that p116(Rip), through its C-terminal coiled-coil domain, interacts directly with the C-terminal leucine zipper of the regulatory myosin-binding subunits of myosin II phosphatase, MBS85 and MBS130. RNA interference-induced knockdown of p116(Rip) inhibits cell spreading and neurite outgrowth in response to extracellular cues, without interfering with the regulation of myosin light chain phosphorylation. We conclude that p116(Rip) is essential for neurite outgrowth and may act as a scaffold to target the myosin phosphatase complex to the actin cytoskeleton.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Actins / metabolism*
Adaptor Proteins, Signal Transducing
Amino Acid Sequence
Animals
Cell Line
Chlorocebus aethiops
Cytoskeleton / chemistry
Cytoskeleton / enzymology
Cytoskeleton / metabolism*
Detergents / pharmacology
Humans
Intracellular Signaling Peptides and Proteins
Mice
Microfilament Proteins / deficiency
Microfilament Proteins / genetics
Microfilament Proteins / metabolism*
Molecular Sequence Data
Myosin-Light-Chain Phosphatase / chemistry
Myosin-Light-Chain Phosphatase / metabolism*
Neurites / metabolism*
Phosphorylation
Protein Binding
Protein Serine-Threonine Kinases / metabolism*
Protein Subunits / metabolism
RNA Interference
Rats
Solubility
rho-Associated Kinases
rhoA GTP-Binding Protein / deficiency
rhoA GTP-Binding Protein / genetics
rhoA GTP-Binding Protein / metabolism*

Substances

Actins
Adaptor Proteins, Signal Transducing
Detergents
Intracellular Signaling Peptides and Proteins
MPRIP protein, human
Microfilament Proteins
Protein Subunits
Protein Serine-Threonine Kinases
rho-Associated Kinases
Myosin-Light-Chain Phosphatase
Mprip protein, rat
p116Rip protein, mouse
rhoA GTP-Binding Protein