Astrocytes are characterized by extensive intercellular communication mediated primarily by gap junction channels composed of @entity16899 . To examine this junctional protein in astrocytic functions, astrocytes were cultured from embryonic @entity19 with a null mutation in the @entity16899 gene (Reaume et al.: Science 267:1831-1834, 1995). Using anti- @entity11404 antibodies, immunoblotting and immunostaining indicated that homozygous null astrocytes were devoid of @entity11404 . They are also deficient in intercellular dye transfer. Astrocytes cultured from heterozygous embryos express significantly lower @entity11404 compared to wild type, and their dye coupling is reduced. Markers of glial differentiation, such as glial fibrillary acidic protein and S100, appeared similar in all genotypes. Measurement of intercellular @entity460 concentration following mechanical stimulation of confluent astrocytes revealed that the number of cells affected by a rise in intracellular @entity460 was reduced in homozygous cultures compared to wild type. In fact, the @entity460 response in homozygous astrocytes was similar to that observed in wild-type astrocytes in the presence of a gap junction blocker. The growth rate of astrocytes lacking @entity11404 was reduced compared to wild-type astrocytes. These results suggest that gap junctional intercellular communication mediated by @entity11404 is not critical for astrocyte differentiation but is likely involved in the regulation of intercellular @entity460 signaling and cell growth.

Altered gap junctional communication, intercellular signaling, and growth in cultured astrocytes deficient in XXXX .

@entity19 :: ('10090', 'Species') :: ['mice'] @entity16899 :: ('14609(Tax:10090)', 'Gene') :: ['connexin43'] @entity11404 :: ('14611(Tax:10090)', 'Gene') :: ['Cx43'] @entity460 :: ('MESH:D002118', 'Chemical') :: ['calcium']
@entity16899 :: (14609(Tax:10090),Gene) :: ['connexin43']
