| Autor: |
Johnson LD; Department of Biology and Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia 23284-2012, USA., Willoughby CA, Burke SH, Paik DS, Jenkins KJ, Tombes RM |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of neurochemistry [J Neurochem] 2000 Dec; Vol. 75 (6), pp. 2380-91. |
| DOI: |
10.1046/j.1471-4159.2000.0752380.x |
| Abstrakt: |
Ca(2+)/calmodulin-dependent protein kinase II (CaMK-II) has been linked to the induction of differentiation in preneuronal cells. In these cells, delta isozymes represent the majority of CaMK-IIs expressed and are activated by differentiation stimuli. To determine whether delta CaMK-IIs are causative or coincident with in vitro differentiation, we overexpressed wild-type, constitutively active, and C-terminal domains of delta and gamma CaMK-II isozymes in mouse P19 and NIH/3T3 cells using high-efficiency transfections. At 1-2 days after transfection, only constitutively active delta CaMK-II isozymes induced branched cellular extensions in both cell types. In P19 cells, retinoic acid induced neurite extensions after 3-4 days; these extensions were coincident with a fourfold increase in endogenous CaMK-II activity. Extensions induced by both retinoic acid and delta CaMK-IIs contained class III beta-tubulin in a discontinuous or beaded pattern. C-terminal CaMK-II constructs disrupted the ability of endogenous CaMK-II to autophosphorylate and blocked retinoic acid-induced differentiation. delta CaMK-II was found along extensions, whereas gamma CaMK-II exhibited a more diffuse, cytosolic localization. These data not only support an extranuclear role for CaMK-II in promoting neurite outgrowth, but also demonstrate CaMK-II isozyme specificity in these early steps of neuronal differentiation. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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