The Cdc42 Effector IRSp53 Generates Filopodia by Coupling Membrane Protrusion with Actin Dynamics*

@article{Lim2008TheCE,
  title={The Cdc42 Effector IRSp53 Generates Filopodia by Coupling Membrane Protrusion with Actin Dynamics*},
  author={Kim Buay Lim and Wenyu Bu and Wah Ing Goh and Esther G. L. Koh and Siew Hwa Ong and Tony Pawson and Thankiah Sudhaharan and Sohail Ahmed},
  journal={Journal of Biological Chemistry},
  year={2008},
  volume={283},
  pages={20454 - 20472}
}
The Cdc42 effector IRSp53 is a strong inducer of filopodia formation and consists of an Src homology domain 3 (SH3), a potential WW-binding motif, a partial-Cdc42/Rac interacting binding region motif, and an Inverse-Bin-Amphiphysins-Rvs (I-BAR) domain.We show that IRSp53 interacts directly with neuronal Wiskott-Aldrich syndrome protein (N-WASP) via its SH3 domain and furthermore that N-WASP is required for filopodia formation as IRSp53 failed to induce filopodia formation in N-WASP knock-out… 
I-BAR domains, IRSp53 and filopodium formation.
Regulation of IRSp53-Dependent Filopodial Dynamics by Antagonism between 14-3-3 Binding and SH3-Mediated Localization
TLDR
This work provides an alternative model of how IRSp53 is recruited (and released) to carry out its functions at lamellipodia and filopodia, and does not conform to current views that the inverse-BAR domain or Cdc42 controlsIRSp53 localization.
Dynamin1 Is a Novel Target for IRSp53 Protein and Works with Mammalian Enabled (Mena) Protein and Eps8 to Regulate Filopodial Dynamics*
TLDR
Dynin1 (Dyn1), the large guanosine triphosphatase, is an interacting partner of IRSp53 through pulldown and Förster resonance energy transfer analysis, and its role in filopodial formation is explored.
mDia1 and WAVE2 Proteins Interact Directly with IRSp53 in Filopodia and Are Involved in Filopodium Formation
TLDR
Findings suggest that mDia1 and WAVE2 are important Src homology 3 domain partners of IRSp53 in forming filopodia, which are dynamic actin-rich cell surface protrusions involved in cell migration, axon guidance, and wound healing.
Rif-mDia1 Interaction Is Involved in Filopodium Formation Independent of Cdc42 and Rac Effectors
TLDR
The dynamics of Rif-induced filopodia are characterized by time lapse imaging of live neuronal cells and it is shown that Rif drives filopodium formation via an independent pathway that does not involve the Cdc42 effectors N-WASP and IRSp 53, the IRSp53 binding partner Mena, or the Rac effectors WAVE1 and WAVE2.
IRSp53 coordinates AMPK and 14-3-3 signaling to regulate filopodia dynamics and directed cell migration
TLDR
It is shown that phosphorylation-dependent inhibition of IRSp53 by 14-3-3 counters activation by Cdc42 and cytoskeletal effectors, resulting in down-regulation of filopodia dynamics and cancer cell migration.
IRSp53 Mediates Podosome Formation via VASP in NIH-Src Cells
TLDR
It is found that the knockdown of IRSp53 by RNAi attenuates podosome formation and migration in Src-transformed NIH3T3 (NIH-Src) cells, and this data highlight the role ofIRSp53 as a linker of small GTPases to VASP for podosomes formation.
LIN7-IRSp53: A novel pathway for filopodia and neurite formation?
TLDR
It is shown that the association between these two proteins is required to promote the formation of filopodia and neurites independently from mDia formin proteins, highlighting novel mechanisms of filanodium and neurite formation.
The Toca-1-N-WASP Complex Links Filopodial Formation to Endocytosis
TLDR
It is reported that Toca-1 induces filopodia and neurites as does N-WASP in N1E115 neuroblastoma cells, and three inhibitors of endocytosis, Dynamin-K44A, Eps15Δ95/295, and clathrin heavy chain RNA interference, block TOCA-1-induced Filopodial formation.
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TLDR
It is demonstrated that IRSp53, a substrate for insulin receptor with unknown function, is the ‘missing link’ between Rac and WAVE, and is essential for Rac to induce membrane ruffling, which stimulates actin polymerization mediated by the Arp2/3 complex.
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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