Requirement of functional ryanodine receptor type 3 for astrocyte migration.
Astrocyte motility plays an important role in the response of the brain to injury and during regeneration. We used two in vitro assays, a wound-healing model and a chemotaxis assay, to study mechanisms that control astrocyte motility. Ryanodine receptors (RyR), intracellular calcium-release channels, modulate intracellular Ca2+ levels, and also motility: 1) blocking RyR with antagonizing concentration of ryanodine (200 microM) strongly attenuated motility and 2) motility of astrocytes cultured from homozygous RyR type 3 knockout mice was impaired strongly compared with wild-type. In contrast, MIP-1a-induced chemotaxis was neither impaired in the presence of ryanodine nor in the cells from the knockout animals. Reverse transcription-polymerase chain reaction (RT-PCR) analysis combined with Western blotting and immunocytochemistry confirmed the expression of RyR type 3, but not type 1 or 2 in cultured and acutely isolated astrocytes. RyR in astrocytes are linked to Ca2+ signaling because the RyR agonist 4-chloro-m-cresol induced a release of Ca2+ from intracellular stores. These results indicate that astrocytes express only RyR type 3 and that this receptor is important for controlling astrocyte motility.
Matyash
Marina
M
Max-Delbrück-Center for Molecular Medicine, Cellular Neuroscience, D-13092 Berlin, Germany.
Matyash
Vitali
V
Nolte
Christiane
C
Sorrentino
Vincenzo
V
Kettenmann
Helmut
H
D000818:Animals; D001253:Astrocytes / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D001921:Brain / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D002633:Chemotaxis; D051379:Mice; D018345:Mice, Knockout; D008954:Models, Biological; D012333:RNA, Messenger / Q000096:biosynthesis; D012433:Ryanodine / Q000494:pharmacology; D019837:Ryanodine Receptor Calcium Release Channel / Q000235:genetics / Q000502:physiology*
D012333:RNA, Messenger; D019837:Ryanodine Receptor Calcium Release Channel; D012433:Ryanodine; D002118:Calcium