RRC ID 35500
著者 Luciano DJ, Hui MP, Deana A, Foley PL, Belasco KJ, Belasco JG.
タイトル Differential control of the rate of 5'-end-dependent mRNA degradation in Escherichia coli.
ジャーナル J Bacteriol
Abstract Many Escherichia coli mRNAs are degraded by a 5'-end-dependent mechanism in which RppH-catalyzed conversion of the 5'-terminal triphosphate to a monophosphate triggers rapid endonucleolytic cleavage by RNase E. However, little is understood about what governs the decay rates of these transcripts. We investigated the decay of three such messages--rpsT P1, yfcZ, and ydfG--to characterize the rate-determining step in their degradation. The steady-state ratio of monophosphorylated to triphosphorylated rpsT P1 and yfcZ mRNA indicates that their decay rate is limited by cleavage of the monophosphorylated intermediate, making RNase E critical for their rapid turnover. Conversely, the decay rate of ydfG is limited by generation of the monophosphorylated intermediate; therefore, either RNase E or its less abundant paralog RNase G is sufficient for rapid ydfG degradation. Although all three transcripts are stabilized when RppH is absent, overproducing RppH does not accelerate their decay, nor does RppH overproduction appear to influence the longevity of most other messages that it targets. The failure of excess RppH to hasten rpsT P1 and yfcZ degradation despite increasing the percentage of each that is monophosphorylated is consistent with the observation that pyrophosphate removal is not the rate-limiting step in their decay. In contrast, neither the ydfG decay rate nor the fraction of ydfG transcripts that are monophosphorylated increases when the cellular concentration of RppH is raised, suggesting that, for some RppH targets, the rate of formation of the monophosphorylated intermediate is limited by an ancillary factor or by a step that precedes pyrophosphate removal.
巻・号 194(22)
ページ 6233-9
公開日 2012-11-1
DOI 10.1128/JB.01223-12
PII JB.01223-12
PMID 22984254
PMC PMC3486407
MeSH Acid Anhydride Hydrolases / genetics Acid Anhydride Hydrolases / metabolism Endoribonucleases / genetics Endoribonucleases / metabolism Escherichia coli / genetics Escherichia coli / metabolism* Escherichia coli Proteins / genetics Escherichia coli Proteins / metabolism Gene Expression Regulation, Bacterial / physiology* Gene Expression Regulation, Enzymologic Immunoblotting Phosphorylation Plasmids RNA, Bacterial / genetics RNA, Bacterial / metabolism* RNA, Messenger / genetics RNA, Messenger / metabolism
IF 3.006
引用数 16
WOS 分野 MICROBIOLOGY
リソース情報
原核生物(大腸菌)