The Critical Role of RNA Processing and Degradation in the Control of Gene Expression

摘要: The continuous degradation and synthesis of prokaryotic mRNAs not only give rise to the metabolic changes that are required as cells grow divide but also rapid adaptation new environmental conditions. In bacteria, RNAs can be degraded by mechanisms act independently, in parallel, target different sites with efficiencies. accessibility for depends on several factors, including RNA higher-order structure, protection translating ribosomes polyadenylation status. Furthermore, have shown determinant post-transcriptional control gene expression. RNases mediate processing, decay quality RNA. divided into endonucleases cleave internally or exonucleases from one extremities. Just Escherichia coli there >20 RNases. RNase E is a single-strand-specific endonuclease critical mRNA E. coli. enzyme interacts exonuclease polynucleotide phosphorylase (PNPase), enolase helicase B (RhlB) form degradosome. However, Bacillus subtilis, this absent, it has other main such J1 III. III cleaves double-stranded family members involved interference eukaryotes. II ubiquitous exonucleases, eukaryotes, they catalytic subunit exosome. pathways execute maturation rRNAs tRNAs, intervene many small noncoding RNAs. general, global regulatory network extremely important regulation levels.