Cellular responses to stress: Comparison of a family of 71–73‐kilodalton proteins rapidly synthesized in rat tissue slices and canavanine‐treated cells in culture

作者：Lawrence E. Hightower, Fredric P. White · 发表于：Journal of Cellular Physiology · 年份：1981 · DOI：10.1002/jcp.1041080216 · 被引用次数：162 · 研究领域：Viral Infectious Diseases and Gene Expression in Insects、Heat shock proteins research、Toxin Mechanisms and Immunotoxins

Cultured rat embryo cells exposed to the L-arginine analogue L-canavanine rapidly accumulated a major 71 kilodalton polypeptide and several minor ones (110, 95, 88, and 78 kilodaltons). Canavanine-treated cultures contained elevated levels of translatable mRNA encoding P71, and the stimulated synthesis of this protein was blocked by actinomycin D, suggesting that P71 is inducible. Rat embryo cells maintained under routine culture conditions synthesized only trace amounts of P71; however, they accumulated an abundant 73 kilodalton protein that was closely related to P71. No kinetic evidence of a precursor-product relationship between P73 and P71 was found. The peptide map of P71 from cultured cells was identical to the map of proteins with the same electrophoretic mobility isolated from incubated slices of rat telencephalon. Previous studies (White, '80a, b, c) have shown that the latter proteins are rapidly synthesized by cells associated with cerebral microvessels in incubated brain slices, but are not detectable in vivo. Herein we present evidence that the synthesis of P71 is not unique to brain slices. Incubated slices of heart, lung, thymus, kidney, spleen, and liver all accumulated an abundant 71 kilodalton size class. The peptide maps of P71 obtained from brain, heart, lung and thymus tissue were similar. The stimulated synthesis of P71 in brain, heart, and lung slices was inhibited strongly by the addition of actinomycin D at the start of incubation. The 71-73 kilodalt...