Spectrin does not redistribute with actin during dBcAMP-induced changes in astrocytes in vitro.

Cells of the astrocyte lineage obtained from mouse neopallium and grown in colony culture have been investigated for a correlation between distributions of F-actin and the common subunit of an erythrocyte actin binding protein, alpha-spectrin (brain fodrin). The cells of the astrocyte lineage at the astroblast stage have F-actin organized in the form of prominent, linearly arranged microfilament bundles. We have demonstrated that spectrin in these cells forms a fine reticulum lining the cell cortex. During the dibutyryl cyclic (dBcAMP)-induced transition from astroblasts to reactive astrocytes, actin-containing microfilaments undergo the dramatic rearrangement from a predominantly linear to a predominantly circumferential spatial organization. remains in the form of a fine reticulum lining the cellular cortex. These remains in the form of a fine reticulum lining the cellular cortex. These findings support the recent notion that spectrin in non-erythroid cells is not essential for maintaining the organization and plasma membrane membrane anchorage of the prominent microfilament bundles.