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Dual pools of actin at presynaptic terminals


, : Dual pools of actin at presynaptic terminals. Journal of Neurophysiology 107(12): 3479-3492

We investigated actin's function in vesicle recycling and exocytosis at lamprey synapses and show that FM1-43 puncta and phalloidin-labeled filamentous actin (F-actin) structures are colocalized, yet recycling vesicles are not contained within F-actin clusters. Additionally, phalloidin also labels a plasma membrane-associated cortical actin. Injection of fluorescent G-actin revealed activity-independent dynamic actin incorporation into presynaptic synaptic vesicle clusters but not into cortical actin. Latrunculin-A, which sequesters G-actin, dispersed vesicle-associated actin structures and prevented subsequent labeled G-actin and phalloidin accumulation at presynaptic puncta, yet cortical phalloidin labeling persisted. Dispersal of presynaptic F-actin structures by latrunculin-A did not disrupt vesicle clustering or recycling or alter the amplitude or kinetics of excitatory postsynaptic currents (EPSCs). However, it slightly enhanced release during repetitive stimulation. While dispersal of presynaptic actin puncta with latrunculin-A failed to disperse synaptic vesicles or inhibit synaptic transmission, presynaptic phalloidin injection blocked exocytosis and reduced endocytosis measured by action potential-evoked FM1-43 staining. Furthermore, phalloidin stabilization of only cortical actin following pretreatment with latrunculin-A was sufficient to inhibit synaptic transmission. Conversely, treatment of axons with jasplakinolide, which induces F-actin accumulation but disrupts F-actin structures in vivo, resulted in increased synaptic transmission accompanied by a loss of phalloidin labeling of cortical actin but no loss of actin labeling within vesicle clusters. Marked synaptic deficits seen with phalloidin stabilization of cortical F-actin, in contrast to the minimal effects of disruption of a synaptic vesicle-associated F-actin, led us to conclude that two structurally and functionally distinct pools of actin exist at presynaptic sites.

US$19.90

PMID: 22457456

DOI: 10.1152/jn.00789.2011


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Rosén, H.; Sunnerhagen, K.S.; Herlitz, J.; Blomstrand, C.; Rosengren, L., 2001: Serum levels of the brain-derived proteins S-100 and NSE predict long-term outcome after cardiac arrest. patients with cardiac arrest have a high mortality and the long-term outcome is doubtful. The prognosis is mainly dependent on clinical parameters. S-100 and neurone specific enolase (NSE) are established biochemical markers of central nervous sys...

Hollenberg, M.D.; Fryklund, L., 1977: Insulin and somatomedins A and B: comparisons of biological activities in cultured human skin-derived fibroblasts. Life Sciences 21(7): 943-950

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Desselle, M.F.ance; Bierne, J., 1995: Transfer and processing of positional information in regenerating nemerteans of the genus Lineus reconstructed with a surplus. 17 allogeneic chimeras and 15 xenogeneic chimeras have been constructed by grafting the anterior parts from 32 Lineus sanguineus transected at the intestinal level onto 17 L. sanguineus and 15 L. lacteus previously decapitated at the oesophageal l...

Zhang Hongwu; Wang Bing en; L.X.angdong, 1998: Model of the structural control of the Badao gold deposit, Yanji, Jilin, China. The Badao gold deposit is a typical Mesozoic volcanic rock-hosted gold deposit. The genesis of the deposit was connected with volcanism and directly controlled by structure. Volcanism was connected with a regional deep fault belt. The connection b...

Lehmann, F.E.; Mancuso, V., 1958: The ultrastructure of the fibrils in the mitotic apparatus of Tubifex after treatment with various fixing agents. Mitoses of somatoblasts and micromeres were used for these studies. The authors describe the superior results obtained by using their previously described, slightly acid, chromate-containing "Fixative E", in the preparation of tissue sec...

Geraldino, G.Cristina.; Polizelli, D.Vichiato.; Pedroso, C.Lobo.; de Toledo, R.Acayaba.; Bertazzi, G.Rejane.Leonardi.; de Toledo, R.Acayaba.; Menin, R.de.Cássia.; Funes, E., 2010: Systemic lupus erythematosus presenting as autoimmune parotitis and pancreatitis - Case Report. Systemic lupus erythematosus (SLE) is a multiorgan autoimmune disease which can present from classical to atypical forms. We discuss the case of a young lady of 29 years-old recently diagnosed with SLE that manifested parotitis and pancreatitis.

Ledingham, J.M.; Pelling, D., 1967: Cardiac output and peripheral resistance in experimental renal hypertension. Circulation Research 21(1): Suppl 2:187+-Suppl 2:187+

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