Induction and/or selective retention of proteins in mammalian cells exposed to cycloheximide

Abstract

Exposure of a number of murine and human cell lines to low graded doses of cycloheximide (CXM) results in a pattern of protein synthesis consisting of enhanced and induced species. These can be divided into two main classes according to molecular weight (20–40 and 70–120 Kd), similar to what has been described for other agents that modify the physiological conditions of growth. In addition, the pronounced synthesis of a hitherto unreported 50‐Kd protein species has been consistently observed in all lines tested. Simultaneous exposure of cells to CXM and actinomycin D results in suppressing synthesis of some but not all protein species observed, indicating that control mechanisms at both transcriptional and posttranscriptional levels may be operative in this system.