Premium
Removal of C6 Astrocytoma Cell Surface Molecules with Phosphatidylinositol Phospholipase C: Effect on Regulation of Neurol Cell Adhesion Molecule Isoforms
Author(s) -
Theveniau Magali,
Guo XiaoJun,
Rage* Pierre,
Rougon GeneViève
Publication year - 1991
Publication title -
journal of neurochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.75
H-Index - 229
eISSN - 1471-4159
pISSN - 0022-3042
DOI - 10.1111/j.1471-4159.1991.tb02100.x
Subject(s) - phosphatidylinositol , second messenger system , phospholipase c , gene isoform , cell adhesion molecule , transmembrane protein , messenger rna , biochemistry , extracellular , biology , cell adhesion , microbiology and biotechnology , cell membrane , cell , chemistry , signal transduction , gene , receptor
Different membrane‐associated isoforms of the Neurol cell adhesion molecules have been described. One of them, N‐CAM120, has been shown to be anchored to the membranes by a complex glycan‐phosphatidylinositol group and to be releasabie, under soluble form, by the bacterial enzyme phosphatidylinositol‐phospholipase C. We used the C6 rat astrocytoma cell line expressing both N‐CAM120 and the transmembrane isoform N‐CAM 140 as a model system. We investigated whether artificial depletion of cell membrane N‐CAM 120 influences the synthesis and the messenger RNA transcript levels of the isoforms of the Neurol cell adhesion molecules. Our results showed an increase in the rate of N‐CAM120 protein synthesis, whereas the expression of N‐CAM140 decreased. Additionally, perturbations in the levels of the 6.7‐kb messenger RNA encoding for N‐CAM 140 were observed, whereas the 2.7‐kb transcript encoding for N‐CAM120 remained stable. Examination of the time course for the reexpression of N‐CAM 120 showed that control levels were recovered after 24 h. We provide evidence that: N‐CAM 120 spontaneously released in the culture medium is not incorporated into the extracellular matrix; however, its concentration is important because, if the medium was changed, cells rapidly released a new pool.