Snapin Specifically Up-Regulates Cav1.3 Ca2+ Channel Variant with a Long Carboxyl Terminus
Autor: | Jung-Ha Lee, Sua Jeong, Jeong-Seop Rhee |
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Jazyk: | angličtina |
Rok vydání: | 2021 |
Předmět: |
two-electrode voltage clamping
QH301-705.5 Xenopus Gating whole-cell patch clamping Catalysis Cav1.3 Inorganic Chemistry ON-gating current Cav1.3 L-type Ca2+ channel Physical and Theoretical Chemistry Biology (General) Molecular Biology QD1-999 Spectroscopy immunostaining biology Chemistry Organic Chemistry Peak current snapin General Medicine biology.organism_classification Computer Science Applications Cell biology Electrophysiology CTL biology.protein Ca2 channels Immunostaining |
Zdroj: | International Journal of Molecular Sciences Volume 22 Issue 20 International Journal of Molecular Sciences, Vol 22, Iss 11268, p 11268 (2021) |
ISSN: | 1422-0067 |
DOI: | 10.3390/ijms222011268 |
Popis: | Ca2+ entry through Cav1.3 Ca2+ channels plays essential roles in diverse physiological events. We employed yeast-two-hybrid (Y2H) assays to mine novel proteins interacting with Cav1.3 and found Snapin2, a synaptic protein, as a partner interacting with the long carboxyl terminus (CTL) of rat Cav1.3L variant. Co-expression of Snapin with Cav1.3L/Cavβ3/α2δ2 subunits increased the peak current density or amplitude by about 2-fold in HEK-293 cells and Xenopus oocytes, without affecting voltage-dependent gating properties and calcium-dependent inactivation. However, the Snapin up-regulation effect was not found for rat Cav1.3S containing a short CT (CTS) in which a Snapin interaction site in the CTL was deficient. Luminometry and electrophysiology studies uncovered that Snapin co-expression did not alter the membrane expression of HA tagged Cav1.3L but increased the slope of tail current amplitudes plotted against ON-gating currents, indicating that Snapin increases the opening probability of Cav1.3L. Taken together, our results strongly suggest that Snapin directly interacts with the CTL of Cav1.3L, leading to up-regulation of Cav1.3L channel activity via facilitating channel opening probability. |
Databáze: | OpenAIRE |
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