SV40 transformation of mouse brain cells: critical role of gene A in maintenance of the transformed phenotype.

Brain cells derived from the NIH Swiss mouse strain have been established in tissue culture. Astrocytic neuroglial cells, identified by morphology and staining properties, predominate. The brain cell culture was successfully transformed with SV40 wild type virus and with a representative early (A239) and late (C219) mutant. When subjected to growth analysis the A239 transformant displayed selective loss of six characteristics of the transformed phenotype at the restrictive temperature (40.5 degrees C): doubling time, saturation density, ability to grow in low serum, efficiency of growth on plastic and on normal brain cell layers, and cloning in soft agar. Temperature shift experiment demonstrated the reversibility of the differences in saturation density. T-antigen was expressed at both temperatures. Alteration in uptake of 2-deoxyglucose was not a characteristic of the transformed phenotype. The cell lines may be utility in brain culture work and in studies on the mechanism of SV40 transformation.