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The p75 neurotrophin receptor mediates the TrkBT1 receptor induced outgrowth of dendritic filopodia in hippocampal neurons

, : The p75 neurotrophin receptor mediates the TrkBT1 receptor induced outgrowth of dendritic filopodia in hippocampal neurons. Society for Neuroscience Abstract Viewer & Itinerary Planner : Abstract No 334 4

The Trk kinases and the p75 receptor (p75NTR) mediate the effects of neurotrophins on neuronal survival, differentiation and synaptic plasticity. The neurotrophin BDNF and its cognate receptor, TrkB.FL, are highly expressed in CNS neurons. Later during postnatal development the truncated TrkB splice variants (TrkB.T1, TrkB.T2) are abundantly expressed in the CNS. However, the signaling mechanisms of these truncated receptors remained elusive. Here we show that overexpression of TrkB.T1 in hippocampal neurons induces the formation of dendritic filopodia. Microcultures of postnatal rat hippocampal neurons were transfected at 8 DIV with expression plasmids coding for TrkB.T1-GFP, and actin containing dendritic filopodia were quantified 3 days later.TrkB.T1 induced the formation of 6.8 +- 0.9 filopodia per 40 mum dendritic length compared to 2.9 +- 0.6 in controls (p<10-5). This effect was independent of neurotrophin binding and was also seen with a mutant TrkB.T1 that lacked the cytoplasmic tail. Coexpression of TrkB.FL had a dominant negative effect on TrkB.T1 induced filopodial growth. Incubation with a neutral sphingomyelinase inhibitor (3 muM spiroepoxide) and with a p75 extracellular epitope antibody (MC192, 8 mug/ml), indicated that the TrkB.T1 effect was mediated by the p75NTR, and subsequent activation of ceramide production. Intriguingly, the TrkB.T1 induced growth of dendritic filopodia was inhibited by coexpression of a dominant negative p75NTR which lacks the cytoplasmic domain, thus supporting signaling of TrkB.T1 via p75NTR.We thus propose a novel signaling pathway initiated by interaction of TrkB.T1 with the p75NTR receptor in the absence of neurotrophins, which modulates dendritic growth via p75NTR signaling cascades. This mechanism could be involved in the generation of synaptic spines.


Other references

Riesinger, P.; Hyvonen, T., 2006: Impact of management on weed species composition in organically cropped spring cereals. Partial Redundancy Analysis (pRDA) was applied to analyse the relationship between weed species composition and agricultural management measures in organically cropped spring cereal fields. Density and dry weight of weed species were assessed in...

Lara, C.; Borrero, J.; Porras, V.; de la Rosa, J.A.; Expósito, F., 2006: Mesenteric lymphangiomatosis. Case report. Lymphangiomas are lesions usually presenting during childhood and are located mainly in the head and neck region; less than 5% are intraabdominal. Lymphangiomatosis is the term used for multifocal or diffuse lymphangiomas. We report the case of a...

Anonymous, 1972: Strawberrry mite. This leaflet contains notes on the habits, appearance and control of Tarsonemus pallidus Banks infesting strawberry in Britain.

Wygodzinsky, P., 1941: Beitrage zur Kenntnis der Dipluren und Thysa-nuren dor Schweiz. Denkschriften der Schweizerischen Naturforschenden Gesellschaft, 74: 113-227

Millar, L.; Cirujales, E.; Cai, F.; Zwaan, J., 1996: Morphological and immunohistochemical studies of chick lens capsule. Investigative Ophthalmology & Visual Science 37(3): S892

Pirsch, J.D.; Kalayoglu, M.; Hafez, G.R.; D'Alessandro, A.M.; Sollinger, H.W.; Belzer, F.D., 1990: Evidence that the vanishing bile duct syndrome is vanishing. Transplantation 49(5): 1015-1018

Gerster, E., 1995: Where to put Mother?. Pflege Zeitschrift 48(10): 579-579

Carlini, E.A.; Green, J.P., 1963: Acetylcholine-Like Activity In Sciatic Nerve. Extracts of sciatic nerve exhibit acetylcholine-like activity that is only partly attributable to acetylcholine. The extracts show relatively greater activity on the rectus abdominis muscle of the frog than on the ileum of the guinea pig. To preve...

Chamberlin Rollin Thomas; Miller W.Z., 1918: Low-angle faulting. Journal of Geology: 1-44. 1918.

Yokobori, S.; Watanabe, A.; Matsumoto, G.; Onda, H.; Masuno, T.; Fuse, A.; Kushimoto, S.; Yokota, H., 2011: Time course of recovery from cerebral vulnerability after severe traumatic brain injury: a microdialysis study. The aim of this study was to evaluate the time course of recovery from cerebral vulnerability, using microdialysis (MD) technique and cerebral vascular autoregulation measurement, to clarify the appropriate timing of subsequent major surgical proc...