Open AccessCoordination de la transcription des RNA 5 S et 23 S et coordination de la maturation du RNA 5 S et de la sous‐unité reibosomique 50 S chez Escherichia coli
Author(s) -
Galibert Francis,
Tiollais Pierre,
Sanfourche Françoise,
Boiron Michel
Publication year - 1971
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1971.tb01404.x
Subject(s) - rna , ribosome , escherichia coli , ribosomal rna , microbiology and biotechnology , transcription (linguistics) , nuclease protection assay , biology , non coding rna , rna polymerase i , chemistry , rna dependent rna polymerase , biochemistry , gene , linguistics , philosophy
The stepwise biosynthesis of Escherichia coli ribosomes can be characterized by a number of precursor ribonucleoprotein particles. It has been shown that 5 S RNA exists as a precursor, pre‐RNA 5 S, prior to its integration into the 40 S relax particle. The present study is concerned with the regulation of 5 S RNA biosynthesis. We report here that: a) the pre‐5‐S‐RNA fraction containing the precursor of 5 S RNA is heterogeneous and consists of a mixture of three (or possibly four) RNA's each precursor to 5 S RNA and each corresponding to a different step in the pathway of 5 S RNA biosynthesis; b) amino acid starvation of an auxotrophic strain of Escherichia coli arrests the maturation of ribonucleoprotein and of 5 S RNA. 23 S and 16 S ribosomal RNA appear in 25 S and 18 S particles and in 38 S and 21 S particles, depending on whether RC relaxed or RC stringent strains were used. 5 S RNA accumulates as 5 S relax RNA or 5 S stringent RNA. The electrophoretic, chromatographic and denaturation analysis of these accumulated RNA's reveal that 5 S relax RNA is less mature than 5 S stringent RNA. The results demonstrate that the maturation of ribosomal particles and 5 S RNA are coordinated together, as the arrest of ribosomal particle maturation is accompained by the arrest of 5 S RNA maturation at a comparable stage; c) by utilizing different methods of cell lysis one can demonstrate that the precursor of 5 S RNA and the immature ribonucleoprotein particles are not found free in the cell but are attached to cellular structures which may be involved in the coordination of the maturation of 5 S RNA and ribosomes; d) kinetic studies of uridine incorporation into RNA during amino acid starvation of an Escherichia coli RC stringent auxotrophic strian reveals that an equimolar amount of 23 S RNA and 5 S RNA are synthesized and one may conclude that these syntheses are coordinated.