Lateral diffusion of inositol 1,4,5-trisphosphate receptor type 1 in Purkinje cells is regulated by calcium and actin filaments

• Published in: Journal of neurochemistry 2010-09, Vol.114 (6), p.1720-1733
• Main Authors: Fukatsu, Kazumi, Bannai, Hiroko, Inoue, Takafumi, Mikoshiba, Katsuhiko
• Format: Article
• Language: English
• Subjects: Actin; Actin Cytoskeleton - physiology; actin filaments; Actins - physiology; Animals; Biological and medical sciences; Calcium; Calcium (intracellular); Calcium - physiology; Cell culture; Cellular biology; Central nervous system; Central neurotransmission. Neuromudulation. Pathways and receptors; Cerebellum; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; dendrite; Dendrites - drug effects; Dendrites - metabolism; Dendritic Spines - drug effects; Dendritic Spines - metabolism; Diffusion; Endoplasmic reticulum; Excitatory Amino Acid Agonists - pharmacology; Filaments; Fluorescence Recovery After Photobleaching; FRAP; Fundamental and applied biological sciences. Psychology; Glutamic Acid - pharmacology; Glutamic acid receptors; Green Fluorescent Proteins - genetics; Inositol 1,4,5-trisphosphate receptors; Inositol 1,4,5-Trisphosphate Receptors - genetics; Inositol 1,4,5-Trisphosphate Receptors - metabolism; IP3R1; IP₃R1; Lateral diffusion; Medical sciences; Membranes; Mice; Mice, Inbred ICR; microfilaments; Neurochemistry; Neurology; Neurons; Purkinje cells; Purkinje Cells - drug effects; Purkinje Cells - metabolism; Purkinje Cells - ultrastructure; Quisqualic Acid - pharmacology; Receptors, Glutamate - physiology; Spine; Tissue Culture Techniques; Vertebrates: nervous system and sense organs
• ISSN: 0022-3042; 1471-4159
• DOI: 10.1111/j.1471-4159.2010.06885.x

J. Neurochem. (2010) 114, 1720-1733. Inositol 1,4,5-trisphosphate receptor type 1 (IP₃R1) is an intracellular Ca²⁺ release channel that plays crucial roles in the functions of Purkinje cells. The dynamics of IP₃R1 on the endoplasmic reticulum membrane and the distribution of IP₃R1 in neurons are thought to be important for the spatial regulation of Ca²⁺ release. In this study, we analyzed the lateral diffusion of IP₃R1 in Purkinje cells in cerebellar slice cultures using fluorescence recovery after photobleaching. In the dendrites of Purkinje cells, IP₃R1 showed lateral diffusion with an effective diffusion constant of approximately 0.30 μm²/s, and the diffusion of IP₃R1 was negatively regulated by actin filaments. We found that actin filaments were also involved in the regulation of IP₃R1 diffusion in the spine of Purkinje cells. Glutamate or quisqualic acid stimulation, which activates glutamate receptors and leads to a Ca²⁺ transient in Purkinje cells, decreased the diffusion of IP₃R1 and increased the density of actin in spines. These findings indicate that the neuronal activity-dependent augmentation of actin contributes to the stabilization of IP₃R1 in spines.