SENSE AND ANTISENSE MODIFICATION OF GLIAL ALPHA-B-CRYSTALLIN PRODUCTION RESULTS IN ALTERATIONS OF STRESS FIBER FORMATION AND THERMORESISTANCE

The phenotypic effects of selectively altering the levels of alpha B-c rystallin in cultured glial cells were analyzed using sense and antise nse approaches. Rat C6 glioma cells and human U-373MG glioma cells wer e transfected with a rat alpha B-crystallin sense cDNA or an antisense cDNA regulated by a Rous sarcoma virus promoter to alter cellular lev els of alpha B-crystallin. The antisense strategy resulted in decrease d alpha B-crystallin levels, as revealed by Western blot and immunocyt ochemical analyses. The reduced alpha B-crystallin expression was acco mpanied by alterations in cellular phenotype: (a) a reduction of cell size and/or a slender cell morphology; (b) a disorganized microfilamen t network; and (c) a reduction of cell adhesiveness. Like HSP27, the p resence of additional alpha B-crystallin protein confers a thermoresis tant phenotype to stable transfectants. Thus, alpha B-crystallin in gl ioma cells plays a role in their thermal resistance and may contribute to the stability of cytoskeletal organization.