title: Onset of ribosome degradation during cessation of growth in BHK-21/C13 cells.
abstract: When BHK-21/C13 cells growing exponentially in 10% serum are transferred to a medium containing only 0.25% serum, cell growth is decreased. After initial changes in RNA synthesis and degradation, protein content of the cultures reaches a plateau and eventually DNA synthesis is arrested. rRNA is relatively stable in exponentially growing cells. Immediately after 'step-down' rRNA degradation commences, but poly(A)-containing RNA does not appear to be degraded any faster than in control cells. Reutilization of RNA precursors has been independently measured and amounts to less than 1%/h for rRNA, insufficient to influence the conclusion that rRNA degradation begins almost immediately after 'step-down'. The degree of reutilization of uridine is much greater for poly(A)-containing RNA than for poly(A)-free RNA.
mesh_terms: D000818:Animals; D002455:Cell Division; D002460:Cell Line; D006224:Cricetinae; D014176:Protein Biosynthesis; D012313:RNA / Q000378:metabolism; D012335:RNA, Ribosomal / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D014529:Uridine / Q000378:metabolism
chemical_list: D012335:RNA, Ribosomal; D012313:RNA; D014529:Uridine