Large-scale imaging of subcellular calcium dynamics of cortical neurons with G-CaMP6-actin.
Understanding the information processing performed by a single neuron requires the monitoring of physiological dynamics from a variety of subcellular compartments including dendrites and axons. In this study, we showed that the expression of a fusion protein, consisting of a Ca²⁺ indicator protein (G-CaMP6) and a cytoskeleton protein (actin), enabled large-scale recording of Ca²⁺ dynamics from hundreds of postsynaptic spines and presynaptic boutons in a cortical pyramidal cell. At dendritic spines, G-CaMP6-actin had the potential to detect localized Ca²⁺ activity triggered by subthreshold synaptic inputs. Back-propagating action potentials reliably induced Ca²⁺ fluorescent increases in all spines. At axonal boutons, G-CaMP6-actin reported action potential trains propagating along axonal collaterals. The detectability of G-CaMP6-actin should contribute toward a deeper understanding of neural network architecture and dynamics at the level of individual synapses.
aGraduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo bBrain Science Institute, Saitama University, Saitama cCenter for Information and Neural Networks, Osaka, Japan.
Chiaki
C
Kobayashi
Masamichi
M
Ohkura
Junichi
J
Nakai
Norio
N
Matsuki
Yuji
Y
Ikegaya
Takuya
T
Sasaki
D000199:Actins / Q000378:metabolism*; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism*; D003712:Dendrites / Q000378:metabolism; D049229:Dendritic Spines / Q000378:metabolism; D018274:Electroporation; D006624:Hippocampus / Q000166:cytology*; D066298:In Vitro Techniques; D052139:Intracellular Calcium-Sensing Proteins / Q000378:metabolism; D009474:Neurons / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure*; D017711:Nonlinear Dynamics; D018408:Patch-Clamp Techniques; D051381:Rats; D017208:Rats, Wistar; D013347:Subcellular Fractions / Q000378:metabolism*
D000199:Actins; D052139:Intracellular Calcium-Sensing Proteins; D002118:Calcium