Cofilin

ADF Actin depolymerization factor/cofilin-like domains E(MFP) 4(5) 4(6) 1CNU... 

Other components, such as a-actinin and actin-related proteins (or ARPs), may also be recruited to the polymerization zone, whereas depolymerizing factors such as ADF and cofilin are apt to be selectively localized in the depolymerization zone. Note Agents that disrupt the formation of activated ABM clusters will also suppress the rate of assembly in the polymerization zone. See ABM-1 ABM-2 Sequences In Actin-Based Motors... 

McGough, A., Pope, B., Chiu, W., and Weeds, W. (1997). Cofilin changes the twist of F-actin Implications for actin filament dynamics and cellular function. J. Cell. Biol. 138, 771-781. 

Fig. 20.3 Schematic showing a pivotal role of RhoA/ROCK activation as a mediator of leptin-induced hypertrophy and its interaction with p38. Activation of RhoA/ROCK results in increased cofilin phosphorylation and altered actin dynamics as demonstrated by a decreased G/F-actin ratio. Stimulation of this pathway results in an exclusive and selective translocation of p38 MAPK into the nucleus which results in an increased protein synthesis to an as yet to be identified mechanism.

Abe, H., Obinata, T., Minamide, L. S., Hamburg, J. R. (1996). Xenopus laevis actin-depolymerizing factor cofilin a phophorylation-regulated protein essential for development. J. Cell Biol. 132, 871-885. 

Lappalainen, P., Drubin, D. G. (1997). Cofilin promotes rapid actin filament turnover in vivo. Nature 388, 78-82. 

Samstag, Y, Dreizler, E. M., Ambach, A., Sczakiel, G., Meuer, S. C. (1996). Inhibition of constitutive serine phosphate activity in T lymphoma cells result in phosphorylation of ppl9/cofilin and induces apoptosis./. Immunol. 156, 4167-4173. 

Wallich, R., Meuee, S. C. (1994). Costimulatory signals for human T-cell activation induce nuclear translocation of ppl9/cofilin. Proc. Natl. Acad. Sci. 

Suzuki, K., Yamaguchi, T, Tanaka, T, Kawanishi,T, Nishimaki-Mogami, T, Yamamoto, K., Tsuji, T, Ieimura, T, Hayakawa, T, Takahashi, A. (1995). Activation induces dephosphorylation of cofilin and its translocation to plasma membranes in neutrophil-like differentiated HL-60 cells./. Biol. Chem. 270, 19551-19556. 

The effects of RhoA activity on spine number and morphology are mediated, at least in part, by the RhoA effector, Rho kinase (Nakayama et al., 2000 Tashiro and Yuste, 2004 Yuste and Bonhoeffer, 2004). Different targets of Rho-kinase have been identified, such as LIMK, myosin light chain (MLC), and MLC phosphatase. Rho-kinase phosphorylates and activates LIMK, which in turn phosphorylates and inactivates the actin depolymerization factor (ADF) cofilin (Maekawa et al., 1999 Sumi et al., 1999 Ohashi et al., 2000 Amano et al., 2001). Phosphorylation of MLC by Rho-kinase results in the stimulation of myosin-actin interactions (Amano et al.,... 

Myosin heavy chain E-cadherin Sec23 Intemexin MAP IB MAP2B MAP 4 Cofilin/actin Spectrin p2... 

Vocgtli W, Madrona A, Wilson D. The structure of Aiplp, a WD repeat protein that regulates Cofilin-mediated actin depolymerization. J Biol Chem 2003 278(36) 34373-34379. 

Ono S. Regulation of actin filament dynamics by actin depolymerizing factor/cofilin and actin-interacting protein 1 new blades for twisted filaments. Biochemistry 2003 42(46) 13363-13370. 

Figure 1. Models of coronin function. A) Speculative model of coronin function (1995, E. L. de Hostos, unpublished) suggesting the involvement of coronin in actin dynamics in partnership with other actin-binding proteins. B) Current model of core coronin functions. " 1) Coronin recruits Arp2/3 complex to existing actin filaments and promotes the formation of branches. 2) Coronin stimulates the activity of cofilin to depolymerize actin filaments at their pointed (ADP-actin containing ends) directly, or by recruiting the SSH1L phosphatase. 3) In the absence of F-actin, coronin inhibits the nucleation activity of Arp2/3.

Cai L, Marshall TW, Uctrccht AC et al. Coronin IB coordinates Arp2/3 complex and cofilin activities at the leading edge. Cell 2007 128 915-29. 

Brieher WM, Kueh H Y, Ballif BA et al. Rapid actin monomer-insensitive depolymerization of Listeria actin comet tails by cofilin, coronin and Aipl. J Cell Biol 2006 175 315-24. 

Hussey PJ, Allwood EG, Smertcnko AP. Actin-binding proteins in the Arabidopsis genome database properties of functionally distinct plant actin-depolymerizing factors/cofilins. Phil Trans R Soc Lond... 

Mohri K, Vorobiev S, Fedorov AA et al. Identification of functional residues on Caenorhabditis elegans actin-interacting protein 1 (UNC-78) for disassembly of actin depolymerizing factor/cofilin-bound actin filaments. J Biol Chem 2004 279 31697-31707. 

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