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Faculty Publications
Intracellular Zn2+ signaling facilitates mossy fiber input-induced heterosynaptic potentiation of direct cortical inputs in hippocampal CA3 pyramidal cells. | |
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Year of publication | 2019 |
Title of paper | Intracellular Zn2+ signaling facilitates mossy fiber input-induced heterosynaptic potentiation of direct cortical inputs in hippocampal CA3 pyramidal cells. |
Author | Eom K, Hyun J, Lee DG, Kim S, Jeong HJ, Kang JS, Ho WK, Lee SH |
Publication in journal | ournal of Neuroscience |
Status of publication | accepted |
Vol | 39(20) |
Link | https://www.jneurosci.org/content/39/20/3812.long 270회 연결 |
Repetitive action potentials (APs) in hippocampal CA3 pyramidal cells (CA3-PCs) backpropagate to distal apical dendrites, and induce calcium and protein tyrosine kinase (PTK)-dependent downregulation of Kv1.2, resulting in long-term potentiation of direct cortical inputs and intrinsic excitability (LTP-IE). When APs were elicited by direct somatic stimulation of CA3-PCs from rodents of either sex, only a narrow window of distal dendritic [Ca2+] allowed LTP-IE because of Ca2+-dependent coactivation of PTK and protein tyrosine phosphatase (PTP), which renders non-mossy fiber (MF) inputs incompetent in LTP-IE induction. High-frequency MF inputs, however, could induce LTP-IE at high dendritic [Ca2+] of the window. We show that MF input-induced Zn2+ signaling inhibits postsynaptic PTP, and thus enables MF inputs to induce LTP-IE at a wide range of [Ca2+]i values. Extracellular chelation of Zn2+ or genetic deletion of vesicular zinc transporter abrogated the privilege of MF inputs for LTP-IE induction. Moreover, the incompetence of somatic stimulation was rescued by the inhibition of PTP or a supplement of extracellular zinc, indicating that MF input-induced increase in dendritic [Zn2+] facilitates the induction of LTP-IE by inhibiting PTP. Consistently, high-frequency MF stimulation induced immediate and delayed elevations of [Zn2+] at proximal and distal dendrites, respectively. These results indicate that MF inputs are uniquely linked to the regulation of direct cortical inputs owing to synaptic Zn2+ signaling. |