Accumulation of water during transformation of cells by an avian sarcoma virus

Abstract

Chick embryo (CE) cells transformed by the Bryan “high titer” strain of Rous sarcoma virus (RSV-BH) are larger than nontransformed CE cells, as determined by direct measurements of diameter and volume. An observed general increase in cell mass is insufficient to fully account for the larger size. However, RSV-BH-transformed cells contain a greater proportion of water, which is reflected in a decrease in cellular density. These changes in size, water content, and density were not found in cells infected with the Schmidt-Ruppin strain of avian sarcoma virus. CE cells infected with a mutant of RSV-BH are morphologically transformed at 37°C but not at 41°C, and after shifting from 41°C to 37°C they become larger, accumulate more water, and band higher in density gradients. These changes occur without a requirement for new RNA or protein synthesis. The noted increase in cellular water may be an early event leading to changes in transcription and translation, culminating in malignancy in cells transformed by RSV-BH.