Gene Activation in WI-38 Fibroblasts Stimulated to Proliferate: Requirement for Protein Synthesis
Year: 1971
Type: article
Abstract: Confluent monolayers of WI-38 human diploid fibroblasts can be stimulated to divide by fresh medium containing 30% fetal-calf serum. Up to 80% of the cells are stimulated to divide, with a peak of DNA synthesis between 15 and 21 hr. 1 hr after the change of medium there is a 70% rise in chromatin template activity. Cycloheximide inhibited the increase in chromatin template activity. A requirement for RNA synthesis was investigated by incubating stimulated and unstimulated cells with 10 mug/ml of actinomycin D. In spite of a 95% inhibition of RNA synthesis in whole cells, purified chromatin from stimulated cells showed the usual increase in template activity. These experiments implicate a requirement for protein synthesis in template activation, and imply that the synthesis of this (or these) protein(s) is independent of RNA synthesis and regulated by a purely translational mechanism.
Authors: Giovanni Rovera, John Farber, Renato Baserga
Institution: Temple University
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2042055227