Annexin VII: an astroglial protein exhibiting a Ca2+-dependent subcellulardistribution

A fundamental issue in neuronal and glial cells is how intracellular rises in Ca2+ are coupled to signaling cascades and changes in subcellular morpho logy. We studied the expression and localization of annexin VII (synexin), a Ca2+-IGTP-dependent membrane fusion protein, in the human CNS. Here, we d emonstrate the presence of two annexin VII isoforms (47 and 51 kDa) in huma n brain tissue as well as its exclusive expression in astroglial cells, An in vitro study of astrocyte-derived Cb rat glioblastoma cells expressing a GFP tagged annexin VII fusion protein demonstrates a sequential redistribut ion of the fusion protein in response to rising intracellular Ca2+ concentr ations. Our findings indicate a role of annexin VII in the regulation of in tracellular Ca2+-dependent processes in astroglial cells. NeuroReport 12:11 39-1144 (C) 2001 Lippincott Williams & Wilkins.