A Cerebellar Purkinje Cell Marker P400 Protein is an Inositol 1,4,5-trisphosphate (InsP3) Receptor Protein. Purification and Characterization of InsP3 Receptor Complex
Overview
Molecular Biology
Authors
Affiliations
P400 protein is a 250 kd glycoprotein, characteristic of the cerebellum, which is accumulated at the endoplasmic reticulum, at the plasma membrane and at the post-synaptic density of Purkinje cells. In this study, we purified inositol 1,4,5-trisphosphate (InsP3) receptor from mouse cerebellum and examined the possibility that P400 protein is identical with cerebellar InsP3 receptor protein. InsP3 receptor was solubilized with Triton X-100 from a post-nuclear fraction of ddY mouse cerebellum and was purified with high yield by sequential column chromatography on DE52, heparin-agarose, lentil lectin-Sepharose and hydroxylapatite. In these chromatographies, P400 protein co-migrated completely with the InsP3 binding activity. The purified receptor is a 250 kd protein with a Bmax of 2.1 pmol/microgram and a KD of 83 nM. It reacted with three different monoclonal antibodies against P400 protein, indicating that P400 protein is the same substance as the InsP3 receptor (P400/InsP3 receptor protein). Electron microscopy of the purified receptor showed a square shape with sides approximately 25 nm long. Binding assays of the cerebella of Purkinje cell-degeneration (pcd) mice with [3H]InsP3 demonstrated that the InsP3 binding sites in the cerebellum are distributed exclusively on the Purkinje cells. Immunohistochemical analysis indicated that P400/InsP3 receptor is present at the dendrites, cell bodies, axons and synaptic boutons of the Purkinje cells.
Conformational motions and ligand-binding underlying gating and regulation in IPR channel.
Fan G, Baker M, Terry L, Arige V, Chen M, Seryshev A Nat Commun. 2022; 13(1):6942.
PMID: 36376291 PMC: 9663519. DOI: 10.1038/s41467-022-34574-1.
Paschou M, Papazafiri P, Charalampous C, Zachariadis M, Dedos S, Doxakis E Cell Mol Life Sci. 2022; 79(7):373.
PMID: 35727337 PMC: 11073139. DOI: 10.1007/s00018-022-04398-9.
Lipid Dyshomeostasis and Inherited Cerebellar Ataxia.
Zhao J, Zhang H, Fan X, Yu X, Huai J Mol Neurobiol. 2022; 59(6):3800-3828.
PMID: 35420383 PMC: 9148275. DOI: 10.1007/s12035-022-02826-2.
Emerging Roles of Calcium Signaling in the Development of Non-Alcoholic Fatty Liver Disease.
Chen C, Hsu L, Chen K, Chiu K, Chen C, Huang K Int J Mol Sci. 2022; 23(1).
PMID: 35008682 PMC: 8745268. DOI: 10.3390/ijms23010256.
Inositol 1,4,5-Trisphosphate Receptors in Human Disease: A Comprehensive Update.
Gambardella J, Lombardi A, Morelli M, Ferrara J, Santulli G J Clin Med. 2020; 9(4).
PMID: 32290556 PMC: 7231134. DOI: 10.3390/jcm9041096.