Actin Depolymerization

Hirshman CA, Zhu D, Panettieri RA, Fmala CW. Actin depolymerization via the beta-adrenoceptor in airway smooth muscle cells a novel PKA-independent pathway. Am J Physiol Cell Physiol 2001 281(5) C1468-1476. 

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

C2 Clostridium botulinum Binary Actin Depolymerization of F-actin (see text)... 

Actin-binding proteins ABP-50, purification, 196, 78 ABP-120, purification, 196, 79 ABP-240 purification, 196, 76 effect on actin depolymerization, 215, 74 extraction, 196, 311 isolation from Dictyostelium discoideum, 196, 70 platelet-derived actin binding proteins [characterization, 215, 58 purification, 215, 58, 64 recombination with actin, 215, 73] 30-kDa Dictyostelium discoideum actin-crosslinking protein [assays, 196, 91 preparation, 196, 84] actin-depolymerizing factor [assay, 196, 132[ DNase assay, 196, 136 platelet-derived a-actinin [characterization, 215, 58 purification, 215, 58, 70 recombination with actin, 215, 73]. 

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. 

Staiger, C.J., Gibbon, B.C., Kovar, D.R., and Zonia, L.E., 1997, Profilin and actin-depolymerizing factor Modulators of actin organization in plants. Trends Plant Sci. 7 275-281. 

Chen, C.Y-H., Cheung, A.Y. and Wu, H-M., 2003, Actin-depolymerizing factor mediates Rac/Rop GTPase-regulated pollen tube growth. Plant Cell 15 237-249. 

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.,... 

Furukawa, K., and Mattson, M.E. 1995. Cytochalasins protect hippocampal neurons against amyloid beta-peptide toxicity evidence that actin depolymerization suppresses Ca2+ influx. JNeurochem 65, 1061-1068. 

Hori, M., Matsuura, Y., Yoshimoto, R., Ozaki, H., Yasumoto, T, and Karaki, H. 1999. Actin depolymerizing action by marine toxin, pectenotoxin-2. Nippon Yakurigaku Zasshi 114, 225P-229P (in Japanese). 

Leira, E, Cabado, A.G., Vieytes, M.R., Roman, Y., Alfonso, A., Botana, L.M., Yasumoto, T, Malaguti, C., and Rossini, G.P. 2002. Characterization of F-actin depolymerization as a major toxic event induced by pectenotoxin-6 in neuroblastoma cells. Biochem Pharmacol 63, 1979-1988. 

Zeng, L.H., Xu, L., Reusing, N.R., Sinatra, P.M., Rothman, S.M., Wong, M. (2007). Kainate seizures cause acute dendritic injury and actin depolymerization in vivo. J. Neurosci. 27 11604-13. 

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. 

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. 

Svitkina TM, Borisy GG. Arp2/3 complex and actin depolymerizing factor/cofilin in dendritic oi aniza-tion and treadmiUing of actin filament array in lameUipodia. J CeU Biol 1999 145(5) 1009-1026. 

Fig. 1. ADP-ribosylafion of Rho by C3 transferases. Rho proteins are regulated by a GTPase cycle. The GTP-binding proteins ore inactive with GDP bound, and active in the GTP-bound form. GDP/GTP exchange is facilitated by guanine nucleotide dissociation stimulator(s) (GDS) and inhibited by guanine nucleotide dissociation inhibitor(s) (GDI). In the active form, Rho protein interacts with its effector(s) and induces several cellular responses, one of which is polymerization of actin. Rho is ADP-ribosylated by C3 transferases at asparagine-41. Most likely, the modification inhibits the interaction of Rho with its effector(s) which results in inhibition of Rho dependent processes (e.g. F-actin depolymerization)...

Fig. 2. Model of the cytopathic effects of actin ADP-ribosylating toxins. The activated binding component of C. botulinum C2 toxin binds to a receptor of the eukaryotic cell. This induces a binding site for the enzyme component (C2I), Most likely, C2I enters the cell by endocytosis and subsequent translocation. In the cell, G-actin is ADP-ribosylated, which inhibits its polymerization and traps actin in the monomeric form. ADP-ribosylated actin binds in a capping protein-like manner to the barbed ends of filaments to inhibit further polymerization at the fast-growing end of F-acfin. The foxin has no effects on the pointed end of filaments where actin depolymerization takes place. Additionally, ADP-ribosylation may affect functions of complexes of acfin wifh binding proteins as examplified in Fig. 1 (From (Aktories, 1990) with permission)...

Panek, J. S., Liu, P. Total Synthesis of the Actin-Depolymerizing Agent (-)-Mycalolide A Application of Chiral Silane-Based Bond Construction Methodology. J. Am. Chem. Soc. 2000,122, 11090-11097. 

Jiang H, Sha SH, Schacht J (2006) Rac/Rho pathway regulates actin depolymerization induced by aminoglycoside antibiotics. J Neurosci Res 83(8) 1544-1551... 

The partial effect of actin depolymerization on synaptic clustering of NMDA receptors is consistent with multiple complex interactions between NMDA receptors and the cytoskeleton. NMDA receptors may also associate with microtubules, albeit indirectly via PSD-95 and CRIPT and MAPIA, and they may even interact with neurofilaments via less well-defined mechanisms. The relevance of microtubules and neurofilaments at postsynaptic sites is still controversial. 

Rosenmund C, Westbrook GL (1993) Calcium-induced actin depolymerization reduces NMDA channel activity. Neuron 70 805-814. 

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