title: Activation of protein kinase A induces neuronal differentiation of HiB5 hippocampal progenitor cells.
abstract: Cyclic AMP-dependent protein kinase (PKA) signaling has been shown to be a critical regulator for neuronal or glial differentiation in the developing brain and several neuronal cell lines. However, the involvement of the PKA signaling cascade in hippocampal neuronal development and differentiation is poorly understood. The present study was performed to investigate whether activation of the PKA pathway directly regulates differentiation of hippocampal progenitor cell line, HiB5. Treatment of hippocampal HiB5 cells with 0.5 mM dibutyryl-cyclic AMP (dbcAMP) at 39 degrees C in N2 medium caused dramatic morphological changes including neurite outgrowth within 24 h and an inhibition of proliferation. During these processes, PKA activity as well as phosphorylation of the cAMP responsive element binding protein (CREB) were augmented. To characterize dbcAMP-induced differentiation of HiB5 cells, the expressions of several neuronal marker genes were investigated. After 24 h of dbcAMP treatment, the expression of NF-H and NF-M neuronal makers increased with a concomitant decrease in nestin (a marker for neural precursor cells) and GFAP an astrocyte marker expression, suggesting that HiB5 cells can develop a neuronal phenotype. Using the doxycycline-inducible, enhanced GFP-fused PKA catalytic subunit alpha (PKAcalpha-EGFP) overexpression system, we found that overexpressed PKAcalpha-EGFP induces neurite outgrowth in HiB5 cells. Taken together, these pharmacological and genetic transfection studies provide compelling evidence for the role of PKA activation on neuronal differentiation in HiB5 hippocampal progenitor cells.
authors.affiliation: School of Biological Sciences, Seoul National University, Seoul, 151-742, South Korea.
authors.forename: Giwon
authors.initials: G
authors.lastname: Kim
authors.forename: Youngshik
authors.initials: Y
authors.lastname: Choe
authors.forename: Junehee
authors.initials: J
authors.lastname: Park
authors.forename: Sehyung
authors.initials: S
authors.lastname: Cho
authors.forename: Kyungjin
authors.initials: K
authors.lastname: Kim
mesh_terms: D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002454:Cell Differentiation / Q000502:physiology*; D002460:Cell Line; D048429:Cell Size; D005576:Colforsin / Q000494:pharmacology; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D049452:Green Fluorescent Proteins; D006624:Hippocampus / Q000166:cytology / Q000378:metabolism*; D007546:Isoquinolines / Q000494:pharmacology; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D009842:Oligopeptides / Q000378:metabolism; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D013234:Stem Cells / Q000166:cytology / Q000502:physiology*; D013449:Sulfonamides
chemical_list: D017362:Cyclic AMP Response Element-Binding Protein; D004791:Enzyme Inhibitors; D007546:Isoquinolines; D008164:Luminescent Proteins; D009842:Oligopeptides; D011993:Recombinant Fusion Proteins; D013449:Sulfonamides; D049452:Green Fluorescent Proteins; D005576:Colforsin; D015124:8-Bromo Cyclic Adenosine Monophosphate; D003994:Bucladesine; C037642:kemptide; D017868:Cyclic AMP-Dependent Protein Kinases; C063509:N-(2-(4-bromocinnamylamino)ethyl)-5-isoquinolinesulfonamide