Microtubule-regulating proteins and cAMP-dependent signaling in neuroblastoma differentiation.
Neurons are highly differentiated cells responsible for the conduction and transmission of information in the nervous system. The proper function of a neuron relies on the compartmentalization of their intracellular domains. Differentiated neuroblastoma cells have been extensively used to study and understand the physiology and cell biology of neuronal cells. Here, we show that differentiation of N1E-115 neuroblastoma cells is more pronounced upon exposure of a chemical analog of cyclic AMP (cAMP), db-cAMP. We next analysed the expression of key microtubule-regulating proteins in differentiated cells and the expression and activation of key cAMP players such as EPAC, PKA and AKAP79/150. Most of the microtubule-promoting factors were up regulated during differentiation of N1E-115 cells, while microtubule-destabilizing proteins were down regulated. We observed an increase in tubulin post-translational modifications related to microtubule stability. As expected, db-cAMP increased PKA- and EPAC-dependent signalling. Consistently, pharmacological modulation of EPAC activity instructed cell differentiation, number of neurites, and neurite length in N1E-115 cells. Moreover, disruption of the PKA-AKAP interaction reduced these morphometric parameters. Interestingly, PKA and EPAC act synergistically to induce neuronal differentiation in N1E-115. Altogether these results show that the changes observed in the differentiation of N1E-115 cells proceed by regulating several microtubule-stabilizing factors, and the acquisition of a neuronal phenotype is a process involving concerted although independent functions of EPAC and PKA.
Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de Chile, Santiago, Chile.|Department of Molecular Pharmacology, University of Groningen, The Netherlands.
Pablo
P
Muñoz-Llancao
Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de Chile, Santiago, Chile.
Cristian
C
de Gregorio
Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de Chile, Santiago, Chile.|Geroscience Center for Brain Health and Metabolism (GERO), Santiago, Chile.
Macarena
M
Las Heras
Department of Molecular Pharmacology, University of Groningen, The Netherlands.
Christopher
C
Meinohl
Department of Molecular Pharmacology, University of Groningen, The Netherlands.
Kevin
K
Noorman
Department of Medical Physiology, University Medical Center Groningen, University of Groningen, The Netherlands.
Erik
E
Boddeke
Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center, Houston, USA.
Xiaodong
X
Cheng
Inserm UMR-1048, Institut des Maladies Métaboliques et Cardiovasculaires, Toulouse, France.|Université de Toulouse III, Paul Sabatier, Toulouse, France.
Frank
F
Lezoualc'h
Department of Molecular Pharmacology, University of Groningen, The Netherlands.
Martina
M
Schmidt
Laboratory of Cell and Neuronal Dynamics, Department of Biology, Faculty of Sciences, Universidad de Chile, Santiago, Chile.|Geroscience Center for Brain Health and Metabolism (GERO), Santiago, Chile.|The Buck Institute for Research on Aging, Novato, USA.
Christian
C
Gonzalez-Billault
D002454:Cell Differentiation; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism*; D006801:Humans; D008868:Microtubule Proteins / Q000378:metabolism*; D009447:Neuroblastoma / Q000235:genetics* / Q000378:metabolism*; D015398:Signal Transduction
D008868:Microtubule Proteins; D017868:Cyclic AMP-Dependent Protein Kinases
EPAC; PKA; cAMP; cytoskeleton proteins; microtubule-associated protein expression; neuronal differentiation