Increased transcription and decreased degradation control and recovery of liver ribosomes after a period of protein starvation.
In the livers of 5-days-protein-depleted mice there is a decrease of 47% of the ribosome mass. When these animals are fed with an adequate diet, ribosome content is restored to the normal value after 1 day of re-feeding. The mechanisms underlying this phenomenon were studied. It was found that: (1) the activity of RNA polymerase I in the nuclei of livers from re-fed animals showed an enhancement of about 2-fold compared with the activity in normal and protein-depleted liver nuclei; (2) ribosome degradation, measured by the disappearance of radioactivity from ribosomal proteins previously labelled by the administration of NaH14CO3 to the mice, stopped during the first day after re-feeding.
D000818:Animals; D004247:DNA / Q000378:metabolism; D004044:Dietary Proteins; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008297:Male; D051379:Mice; D011488:Protein Deficiency / Q000378:metabolism*; D012318:RNA Polymerase I / Q000378:metabolism; D012335:RNA, Ribosomal / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D014158:Transcription, Genetic
D004044:Dietary Proteins; D012335:RNA, Ribosomal; D004247:DNA; D012318:RNA Polymerase I