TY - JOUR
T1 - Localization of SK2 channels relative to excitatory synaptic sites in the mouse developing Purkinje cells
AU - Ballesteros-Merino, Carmen
AU - Martínez-Hernández, José
AU - Aguado, Carolina
AU - Watanabe, Masahiko
AU - Adelman, John P.
AU - Luján, Rafael
N1 - Publisher Copyright:
© 2014 Ballesteros-Merino, Martínez-Hernández, Aguado, Watanabe, Adelman and Luján.
PY - 2014/12/15
Y1 - 2014/12/15
N2 - Small-conductance, Ca2+-activated K+ (SK) channels regulate neuronal excitability in a variety of ways. To understand their roles in different neuronal subtypes it is important to determine their precise subcellular distribution. Here, we used biochemical, light microscopy immunohistochemical and immunoelectron microscopy techniques, combined with quantitative approaches, to reveal the expression and subcellular localization patterns of SK2 in the developing cerebellum. Using western blots, the SK2 protein showed a progressive increase during postnatal development. At the light microscopic level, SK2 immunoreactivity was very prominent in the developing Purkinje cells (PC), particularly in the molecular layer (ML). Electron microscopy revealed that throughout development SK2 was mostly detected at the extrasynaptic and perisynaptic plasma membrane of dendritic shafts and dendritic spines of PCs. However, there was some localization at axon terminals as well. Quantitative analyses and 3D reconstructions further revealed a progressive developmental change of SK2 on the surface of PCs from dendritic shafts to dendritic spines. Together, these results indicate that SK2 channels undergo dynamic spatial regulation during cerebellar development, and this process is associated with the formation and maturation of excitatory synaptic contacts to PCs.
AB - Small-conductance, Ca2+-activated K+ (SK) channels regulate neuronal excitability in a variety of ways. To understand their roles in different neuronal subtypes it is important to determine their precise subcellular distribution. Here, we used biochemical, light microscopy immunohistochemical and immunoelectron microscopy techniques, combined with quantitative approaches, to reveal the expression and subcellular localization patterns of SK2 in the developing cerebellum. Using western blots, the SK2 protein showed a progressive increase during postnatal development. At the light microscopic level, SK2 immunoreactivity was very prominent in the developing Purkinje cells (PC), particularly in the molecular layer (ML). Electron microscopy revealed that throughout development SK2 was mostly detected at the extrasynaptic and perisynaptic plasma membrane of dendritic shafts and dendritic spines of PCs. However, there was some localization at axon terminals as well. Quantitative analyses and 3D reconstructions further revealed a progressive developmental change of SK2 on the surface of PCs from dendritic shafts to dendritic spines. Together, these results indicate that SK2 channels undergo dynamic spatial regulation during cerebellar development, and this process is associated with the formation and maturation of excitatory synaptic contacts to PCs.
KW - Cerebellar development
KW - Electron microscopy
KW - Immunohistochemistry
KW - Purkinje cells
KW - SK2 channels
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U2 - 10.3389/fnana.2014.00154
DO - 10.3389/fnana.2014.00154
M3 - Article
AN - SCOPUS:84918807261
SN - 1662-5129
VL - 8
JO - Frontiers in Neuroanatomy
JF - Frontiers in Neuroanatomy
IS - DEC
M1 - 154
ER -