期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1986
卷号:83
期号:1
页码:120-124
DOI:10.1073/pnas.83.1.120
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:The isolation of a temperature-sensitive allele of RNase II (rnb) by in vitro mutagenesis has permitted the demonstration that RNase II and polynucleotide phosphorylase (PNPase) are required for cell viability and mRNA turnover in Escherichia coli. Double-mutant strains carrying the pnp-7 and rnb-500 alleles (PNPase deficient and RNase II thermolabile) ceased growing in Luria broth within 30 min after shift to the nonpermissive temperature. Cessation of growth was accompanied by an accumulation of mRNA fragments 100-1500 nucleotides long. In contrast, single-mutant and wild-type control strains grew normally at the nonpermissive temperature and did not accumulate mRNA. No significant changes in rRNA patterns were observed in any of the strains.