Caveolin isoform expression during differentiation of C6 glioma cells.
Submitted by Walter Silva on
Title | Caveolin isoform expression during differentiation of C6 glioma cells. |
Publication Type | Journal Article |
Year of Publication | 2005 |
Authors | Silva, WI, Maldonado, HM, Velázquez, G, Rubio-Dávila, M, Miranda, JD, Aquino, E, Mayol, N, Cruz-Torres, A, Jardón, J, Salgado-Villanueva, IK |
Journal | Int J Dev Neurosci |
Volume | 23 |
Issue | 7 |
Pagination | 599-612 |
Date Published | 2005 Nov |
ISSN | 0736-5748 |
Keywords | Animals, Astrocytes, Blotting, Western, Caveolin 1, Cell Differentiation, Cell Fractionation, Cell Line, Tumor, Centrifugation, Density Gradient, DNA Primers, Down-Regulation, Electrophoresis, Polyacrylamide Gel, Fluorescent Antibody Technique, Indirect, Glial Fibrillary Acidic Protein, Glioma, Isomerism, Microscopy, Confocal, Rats, Reverse Transcriptase Polymerase Chain Reaction, RNA, Messenger |
Abstract | Caveolae, a specialized form of lipid rafts, are cholesterol- and sphingolipid-rich membrane microdomains implicated in potocytosis, endocytosis, transcytosis, and as platforms for signal transduction. One of the major constituents of caveolae are three highly homologous caveolin isoforms (caveolin-1, caveolin-2, and caveolin-3). The present study expands the analysis of caveolin isoform expression in C6 glioma cells. Three complementary approaches were used to assess their differential expression during the dibutyryl-cyclic AMP-induced differentiation of C6 cells into an astrocyte-like phenotype. Immunoblotting, conventional RT-PCR, and real-time RT-PCR analysis established the expression of the caveolin-3 isoform in C6 cells, in addition to caveolin-1 and caveolin-2. Similar to the other isoforms, caveolin-3 was associated with light-density, detergent-insoluble caveolae membrane fractions obtained using sucrose-density gradient centrifugation. The three caveolin isoforms display different temporal patterns of mRNA/protein expression during the differentiation of C6 cells. Western blot and real-time RT-PCR analysis demonstrate that caveolin-1 and caveolin-2 are up-regulated during the late stages of the differentiation of C6 cells. Meanwhile, caveolin-3 is gradually down-regulated during the differentiation process. Indirect immunofluorescence analysis via laser-scanning confocal microscopy reveals that the three caveolin isoforms display similar subcellular distribution patterns. In addition, co-localization of caveolin-1/caveolin-2 and caveolin-1/caveolin-3 was detected in both C6 glioma phenotypes. The findings reveal a differential temporal pattern of caveolin gene expression during phenotypic differentiation of C6 glioma cells, with potential implications to developmental and degenerative events in the brain. |
DOI | 10.1016/j.ijdevneu.2005.07.007 |
Alternate Journal | Int. J. Dev. Neurosci. |
PubMed ID | 16135403 |
Grant List | GM61838 / GM / NIGMS NIH HHS / United States S06-GM08224 / GM / NIGMS NIH HHS / United States S06-GM50695 / GM / NIGMS NIH HHS / United States |