Localization of two forms of phospholipase C-beta 1, a and b, in C6Bu-1 cells

Abstract

Phospholipase C-beta 1 (PLC-beta 1), one of the PLC-beta isozymes, exists as two immunologically distinguishable polypeptides of 150 (PLC-beta 1a) and 140 kDa (PLC-beta 1b) which are encoded in two distinct transcripts and generated by alternative splicing of a single gene, In this study, the subcellular localization of the two phospholipases C-beta 1 proteins was examined in rat CGBu-1 glioma cells using immunological techniques, Immunoblot analysis revealed that the two forms of PLC-beta 1 were detectible in both cytosolic and nuclear fractions, PLC-beta 1a appeared to be located preferentially in the cytosol, whereas PLC-beta 1b was found predominantly in the nuclei of C6Bu-1 cells, Immunocytochemical experiments confirmed the differential localization of the two PLC-beta 1 species in C6Bu-1 cells. These results suggest that the two PLC-beta 1 proteins may have different physiological roles in the cell. (C) 1998 Elsevier Science B.V.