Receptor-Selective Diffusion Barrier Enhances Sensitivity of Astrocytic Processes to Metabotropic Glutamate Receptor Stimulation

Misa Arizono1,2, Hiroko Bannai1*, Kyoko Nakamura3,4, Fumihiro Niwa1,5, Masahiro Enomoto1, Toru Matsu-ura1, Akitoshi Miyamoto1,2, Mark W. Sherwood1, Takeshi Nakamura3, and Katsuhiko Mikoshiba

Metabotropic glutamate receptor (mGluR)–dependent calcium ion (Ca2+) signaling in astrocytic processes regulates synaptic transmission and local blood flow essential for brain function. However, because of difficulties in imaging astrocytic processes, the subcellular spatial organization of mGluR-dependent Ca2+ signaling is not well characterized and its regulatory mechanism remains unclear. Using genetically encoded Ca2+ indicators, we showed that despite global stimulation by an mGluR agonist, astrocyte processes intrinsically exhibited a marked enrichment of Ca2+ responses. Immunocytochemistry indicated that these polarized Ca2+ responses could be attributed to increased density of surface mGluR5 on processes relative to the soma. Single-particle tracking of surface mGluR5 dynamics revealed a membrane barrier that blocked the movement of mGluR5 between the processes and the soma. Overexpression of mGluR or expression of its carboxyl terminus enabled diffusion of mGluR5 between the soma and the processes, disrupting the polarization of mGluR5 and of mGluR-dependent Ca2+ signaling. Together, our results demonstrate an mGluR5-selective diffusion barrier between processes and soma that compartmentalized mGluR Ca2+ signaling in astrocytes and may allow control of synaptic and vascular activity in specific subcellular domains.

• 以上资料由西亚试剂：http://www.xiyashiji.com/ 提供此产品的详细信息如密度,含量,分子式,分子量等均可在西亚官网查询   
• 相关产品如汞乙酸汞氯化汞氧化汞碘化汞硫酸汞硝酸汞溴化汞硝酸亚汞氯化亚汞乙酸苯汞碘化汞钾硫氰酸汞氯化氨基汞三氯生三氯氧磷三氯乙烯水合氯醛三氯化磷三氯化钌三氯化钛三氯化铱三氯化铑三氯硫磷三氯乙烷三氯甲烷三氯卡班TCC1,3,5-三氯苯1,2,4-三氯苯1,2,3-三氯苯无水氯化铝三氯乙酸酐三氯乙酸钠碘甲烷二碘甲烷三碘甲烷 三氟碘甲烷硫酸二甲酯氯磺酸苯硫酚苯硫酚钠3-氨基苯硫酚2,6-二氯苯硫酚2,4-二氯苯硫酚2,5-二氯苯硫酚2-甲氧基苯硫酚等均有销售.欢迎订购