The Sm‐like protein Hfq regulates polyadenylation dependent mRNA decay in Escherichia coli

The majority of Escherichia coli mRNAs undergo post-transcriptional modification in exponentially growing cells

“…The majority of the transcripts in each group were part of operons, some of which contained up to 12 ORFs. In agreement with our previous results ( 12 ), of the ORFs showing high levels of post-transcriptional modification, ∼72% were linked to a Rho-independent transcription terminator either as a monocistronic or part of a polycistronic mRNA. In most cases, every gene within a polycistronic transcript that was terminated in a Rho-independent fashion was post-transcriptionally modified [e.g.…”

“…In addition, the direct sequencing of cDNAs demonstrated the presence of mainly poly(A) tails on the ompA mRNA which contains a Rho-independent transcription terminator compared to the absence of such tails on the pcnB-folK dicistronic mRNA which terminates in a Rho-dependent fashion ( Figure 3 ). These data are in agreement with our previous sequencing analysis of the lpp , rpsO and trxA mRNAs ( 5 , 11 , 12 ).…”

The majority of Escherichia coli mRNAs undergo post-transcriptional modification in exponentially growing cells

“…The majority of the transcripts in each group were part of operons, some of which contained up to 12 ORFs. In agreement with our previous results ( 12 ), of the ORFs showing high levels of post-transcriptional modification, ∼72% were linked to a Rho-independent transcription terminator either as a monocistronic or part of a polycistronic mRNA. In most cases, every gene within a polycistronic transcript that was terminated in a Rho-independent fashion was post-transcriptionally modified [e.g.…”

“…In addition, the direct sequencing of cDNAs demonstrated the presence of mainly poly(A) tails on the ompA mRNA which contains a Rho-independent transcription terminator compared to the absence of such tails on the pcnB-folK dicistronic mRNA which terminates in a Rho-dependent fashion ( Figure 3 ). These data are in agreement with our previous sequencing analysis of the lpp , rpsO and trxA mRNAs ( 5 , 11 , 12 ).…”

The Response Regulator SprE (RssB) Modulates Polyadenylation and mRNA Stability inEscherichia coli

“…2), we tested to determine if wild-type SprE was involved in the regulation of intracellular levels of polyadenylation. In agreement with previously reported results in the MG1655 genetic background (27,33), poly(A) levels were reduced 70% and 60% in ⌬pcnB and hfq-1 strains, respectively (Fig. 2), while deletion of the sprE locus caused a 40 to 50% reduction in poly(A) levels in exponentially growing cells (Fig.…”

The ribonuclease polynucleotide phosphorylase can interact with small regulatory RNAs in both protective and degradative modes

“…Thus, we first tested whether or not Hfq interacts with PNPase-FLAG via a coimmunoprecipitation assay. Consistent with previous findings that Hfq copurifies with PNPase (Mohanty et al 2004; Butland et al 2005; Obregon et al 2015), Hfq coimmunoprecipitated with PNPase-FLAG (Fig. 1C; Supplemental Table S4).…”

“…6). Consistent with previous findings (Mohanty et al 2004; Butland et al 2005; Morita et al 2005; Obregon et al 2015), PNPase copurifies with Hfq and is likely to form complexes that are at least transient in vivo (Fig. 1C; Supplemental Table S4).…”

The majority of Escherichia coli mRNAs undergo post-transcriptional modification in exponentially growing cells

“…The majority of the transcripts in each group were part of operons, some of which contained up to 12 ORFs. In agreement with our previous results ( 12 ), of the ORFs showing high levels of post-transcriptional modification, ∼72% were linked to a Rho-independent transcription terminator either as a monocistronic or part of a polycistronic mRNA. In most cases, every gene within a polycistronic transcript that was terminated in a Rho-independent fashion was post-transcriptionally modified [e.g.…”

“…In addition, the direct sequencing of cDNAs demonstrated the presence of mainly poly(A) tails on the ompA mRNA which contains a Rho-independent transcription terminator compared to the absence of such tails on the pcnB-folK dicistronic mRNA which terminates in a Rho-dependent fashion ( Figure 3 ). These data are in agreement with our previous sequencing analysis of the lpp , rpsO and trxA mRNAs ( 5 , 11 , 12 ).…”

The Response Regulator SprE (RssB) Modulates Polyadenylation and mRNA Stability inEscherichia coli

“…2), we tested to determine if wild-type SprE was involved in the regulation of intracellular levels of polyadenylation. In agreement with previously reported results in the MG1655 genetic background (27,33), poly(A) levels were reduced 70% and 60% in ⌬pcnB and hfq-1 strains, respectively (Fig. 2), while deletion of the sprE locus caused a 40 to 50% reduction in poly(A) levels in exponentially growing cells (Fig.…”

The ribonuclease polynucleotide phosphorylase can interact with small regulatory RNAs in both protective and degradative modes

“…Thus, we first tested whether or not Hfq interacts with PNPase-FLAG via a coimmunoprecipitation assay. Consistent with previous findings that Hfq copurifies with PNPase (Mohanty et al 2004; Butland et al 2005; Obregon et al 2015), Hfq coimmunoprecipitated with PNPase-FLAG (Fig. 1C; Supplemental Table S4).…”

“…6). Consistent with previous findings (Mohanty et al 2004; Butland et al 2005; Morita et al 2005; Obregon et al 2015), PNPase copurifies with Hfq and is likely to form complexes that are at least transient in vivo (Fig. 1C; Supplemental Table S4).…”

The majority of Escherichia coli mRNAs undergo post-transcriptional modification in exponentially growing cells

“…The majority of the transcripts in each group were part of operons, some of which contained up to 12 ORFs. In agreement with our previous results ( 12 ), of the ORFs showing high levels of post-transcriptional modification, ∼72% were linked to a Rho-independent transcription terminator either as a monocistronic or part of a polycistronic mRNA. In most cases, every gene within a polycistronic transcript that was terminated in a Rho-independent fashion was post-transcriptionally modified [e.g.…”

“…In addition, the direct sequencing of cDNAs demonstrated the presence of mainly poly(A) tails on the ompA mRNA which contains a Rho-independent transcription terminator compared to the absence of such tails on the pcnB-folK dicistronic mRNA which terminates in a Rho-dependent fashion ( Figure 3 ). These data are in agreement with our previous sequencing analysis of the lpp , rpsO and trxA mRNAs ( 5 , 11 , 12 ).…”

The Response Regulator SprE (RssB) Modulates Polyadenylation and mRNA Stability inEscherichia coli

“…2), we tested to determine if wild-type SprE was involved in the regulation of intracellular levels of polyadenylation. In agreement with previously reported results in the MG1655 genetic background (27,33), poly(A) levels were reduced 70% and 60% in ⌬pcnB and hfq-1 strains, respectively (Fig. 2), while deletion of the sprE locus caused a 40 to 50% reduction in poly(A) levels in exponentially growing cells (Fig.…”

The ribonuclease polynucleotide phosphorylase can interact with small regulatory RNAs in both protective and degradative modes

“…Thus, we first tested whether or not Hfq interacts with PNPase-FLAG via a coimmunoprecipitation assay. Consistent with previous findings that Hfq copurifies with PNPase (Mohanty et al 2004; Butland et al 2005; Obregon et al 2015), Hfq coimmunoprecipitated with PNPase-FLAG (Fig. 1C; Supplemental Table S4).…”

“…6). Consistent with previous findings (Mohanty et al 2004; Butland et al 2005; Morita et al 2005; Obregon et al 2015), PNPase copurifies with Hfq and is likely to form complexes that are at least transient in vivo (Fig. 1C; Supplemental Table S4).…”