ライフサイエンスコーパス: tmRNA

1 tmRNA and SmpB have been found in all bacteria and are e

2 tmRNA combines tRNA and mRNA properties and helps bacter

3 tmRNA contains a transfer RNA (tRNA)-like domain (TLD),

4 tmRNA is a small regulatory RNA that is ubiquitous in ba

5 tmRNA is a versatile and highly conserved bacterial mole

6 tmRNA is strongly attached to the 30S subunit head by mu

7 tmRNA rescues stalled ribosomes in eubacteria by forcing

8 tmRNA, encoded by the ssrA gene, is a bifunctional molec

9 tmRNA-SmpB interacts with translational complexes stalle

10 from 10 bacterial groups for a total of 274 tmRNA sequences have been added.

11 ibosome recycling factor do not constitute a tmRNA-independent rescue pathway, as previously suggeste

12 e capable of rescuing stalled ribosomes in a tmRNA-independent manner.

13 Here, we present the crystal structure of a tmRNA fragment, SmpB and elongation factor Tu bound to t

14 SmpB, a tmRNA-binding protein, protects SsrA RNA from RNase R de

15 bility using an unrelated sequence yielded a tmRNA mutant with nearly wild-type activity.

16 pB protein that restore the function of A86C tmRNA in vivo.

17 he plastid, where mature SmpB could activate tmRNA.

18 Additionally, tmRNA.SmpB-mediated SsrA peptide tagging was significant

19 A complex of alanyl-tmRNA (which functions as a tRNA and mRNA), SmpB protein

20 ial sRNAs (6S, RNaseP_bact_a, ffs, and alpha-tmRNA) was next confirmed by Northern hybridization.

21 ficantly lower levels of A-site cleavage and tmRNA.SmpB activity.

22 d function modulate A-site mRNA cleavage and tmRNA.SmpB activity.

23 actor 3 did not have comparable effects, and tmRNA was incapable of attacking TnaC-tRNA(2)(Pro) in st

24 bacteria are also regulated by RNase III and tmRNA.

25 Fs encoding a putative signaling peptide and tmRNA in T. maritima is intriguing, since this overlappi

26 ependent on the presence of SmpB protein and tmRNA, suggesting a requirement for active transtranslat

27 endent on the activities of SmpB protein and tmRNA.

28 The original mRNA is released and tmRNA becomes the template for translation of a 10-amino

29 P RNA, signal-recognition particle RNA, and tmRNA is facilitated by their cognate polymerase pausing

30 To probe interactions between S1 and tmRNA, truncated variants missing one or more of the six

31 However, the binding of SmpB and tmRNA does not alter RNase R activity.

32 nditions roughly similar numbers of SmpB and tmRNA molecules are present in cells.

33 To elucidate the contributions of SmpB and tmRNA to RNase R recruitment, we evaluated Escherichia c

34 ignificance of conserved regions of SmpB and tmRNA to the trans-translation process.

35 trans-Translation, orchestrated by SmpB and tmRNA, is the principal eubacterial pathway for resolvin

36 examine 87 Escherichia coli MG1655 tRNA and tmRNA genes and their orthologues in E.coli EDL933, E.co

37 Our algorithm generates a list of tRNA and tmRNA genes, uses each as the query for a BLAST search o

38 contents and contexts of bacterial tRNA and tmRNA genes, which are known insertion hotspots for geno

39 riguing, since this overlapping arrangement (tmRNA associated with putative small ORFs) was found to

40 its protein partner, SmpB (small protein B), tmRNA enters stalled ribosomes and transfers an Ala resi

41 When protein synthesis stalls in bacteria, tmRNA acts first as a surrogate tRNA and then as an mRNA

42 The bacterial tmRNA.SmpB system facilitates recycling of stalled trans

43 The bacterial tmRNA.SmpB system recycles stalled translation complexes

44 lineages suggests that loop-opening benefits tmRNA function.

45 bosomes does not involve competition between tmRNA and other translation factors for A-sites that are

46 domain (R1) plays a critical role in binding tmRNA and mRNA but requires additional N- or C-terminal

47 Ribosomal protein S1 binds tmRNA, but its functional role in tmRNA-mediated tagging

48 er from termination-paused ribosomes in both tmRNA(+) and DeltatmRNA cells, whereas other termination

49 stop mRNA, tmRNA levels did not increase but tmRNA-mediated tagging increased substantially.

50 stop codons was dramatically accelerated by tmRNA.SmpB.

51 the extent of ribosome pausing as assayed by tmRNA-mediated tagging of the nascent polypeptide.

52 Therefore, ArfA levels are controlled by tmRNA through ssrA-peptide tagging and proteolysis.

53 nce called the ssrA tag, which is encoded by tmRNA and allows normal termination and release of ribos

54 om truncated mRNA and therefore regulated by tmRNA tagging activity.

55 ective messenger RNAs (mRNAs) are rescued by tmRNA, an approximately 300-nucleotide-long molecule tha

56 d during protein synthesis can be rescued by tmRNA, which acts first as a tRNA and then as an mRNA to

57 ng, and the rescuing of stalled ribosomes by tmRNA.

58 s with RNase R in vitro and is stimulated by tmRNA.

59 over, +1 frameshifting was not suppressed by tmRNA.SmpB activity, suggesting that recoding and riboso

60 proteins were identified that are tagged by tmRNA under normal growth conditions.

61 In G(1)-phase cells, tmRNA was found in regularly spaced foci indicative of a

62 f IdeR and Zur regulated mRNAs and to cleave tmRNA in M. tuberculosis, Escherichia coli and Mycobacte

63 assays to study the role of Escherichia coli tmRNA in trans-translation.

64 Although not essential in Escherichia coli, tmRNA activity is essential for bacterial survival under

65 proposed secondary structure combines common tmRNA features differently from the structures of other

66 Lists of the tmRNAs and the corresponding tmRNA-encoded tag-peptides are presented in alphabetical

67 In Caulobacter crescentus, tmRNA was localized in a cell-cycle-dependent manner.

68 that the AAA+ Lon protease can also degrade tmRNA-tagged proteins, but with much lower efficiency.

69 RNase R, the nuclease that degrades tmRNA, was localized in a helix-like pattern that was se

70 ough A-site-cleaved mRNAs were not detected, tmRNA-mediated ssrA tagging after SecM glycine 165 was o

71 In many species, mutations that disrupt tmRNA activity cause defects in growth or development.

72 s of the pseudoknots and protein SmpB during tmRNA folding, maturation, and protein synthesis.

73 the secondary and tertiary structure of each tmRNA molecule.

74 he emergence of mutant strains with elevated tmRNA transcription.

75 res with translation termination and elicits tmRNA.SmpB activity.

76 Some plastid genomes encode tmRNA, but smpB genes have only been reported from bacte

77 uitous in eubacteria, the ssrA gene encoding tmRNA is not essential for the viability of Escherichia

78 Protein SmpB enhanced tmRNA processing, suggesting a new role for SmpB in tran

79 o gain further insights, we used established tmRNA and SmpB variants that impact distinct stages of t

80 tion, we report the discovery of an extended tmRNA tag and extensive ladder-like pattern of endogenou

81 Pseudoknot 4 not only facilitated tmRNA maturation but also promoted tagging.

82 ely disrupts their interaction, facilitating tmRNA-SmpB binding.

83 Diatom SmpB was active for tmRNA translation with bacterial components in vivo and

84 able to bind ribosomes, and its affinity for tmRNA was only slightly diminished.

85 ribosomal binding protein) is essential for tmRNA (ssrA) function.

86 ng no other known function, is essential for tmRNA activity.

87 ral element that is considered essential for tmRNA function based on the analysis of pk1 mutants in v

88 cated E. coli SmpB was likewise inactive for tmRNA translation but was still able to bind ribosomes,

89 statistical analysis revealed that only for tmRNA was the absence nonrandom.

90 somal elements are specifically required for tmRNA activity.

91 ribosomes, indicating two distinct roles for tmRNA-SmpB.

92 Using a genetic selection for tmRNA activity in Escherichia coli, we identified mutati

93 ion of pk1 at 20% per base and selection for tmRNA activity yielded sequences that retain the same ps

94 While ACA motifs are absent from tmRNA, 4.5S RNA, and seven of the eight 5S rRNAs, statis

95 The structure reveals how tmRNA could move through the ribosome despite its compli

96 This evaluation showed that while the hybrid tmRNA supported nascent polypeptide tagging and ribosome

97 We observed that the hybrid tmRNA was active but resulted in less accurate selection

98 propose that the unusual bias against ACA in tmRNA may have coevolved with the acquisition of MazF.

99 We conclude that the role of pk1 in tmRNA function is purely structural and that it can be r

100 -paused ribosomes was slightly more rapid in tmRNA(+) cells (T(1/2)=22+/-2.2 s) than in DeltatmRNA ce

101 mmediately upstream of this coding region in tmRNA, is a structural element that is considered essent

102 the target arginine codons, and resulted in tmRNA-mediated SsrA-peptide tagging of the nascent polyp

103 minal tail of SmpB play an important role in tmRNA accommodation.

104 and PNPase do not play a significant role in tmRNA-facilitated disposal of aberrant mRNAs.

105 n S1 binds tmRNA, but its functional role in tmRNA-mediated tagging is uncertain.

106 ssibility that S1 plays little or no role in tmRNA-mediated tagging.

107 so reveals a tail-dependent role for SmpB in tmRNA translation that supersedes a simple role of linki

108 howed that the discrimination against ACA in tmRNAs was seen mostly in enterobacteria.

109 e to rpsL(P90K) cells but failed to increase tmRNA.SmpB activity.

110 strain, and selective pressure for increased tmRNA activity was indicated by the emergence of mutant

111 ere, we show that deletion of rluD increases tmRNA activity on ribosomes undergoing release factor 2

112 ctivities that are influenced by independent tmRNA and SmpB determinants.

113 ded that the C889U mutation does not inhibit tmRNA activity per se but interferes with an upstream st

114 alling sequence, suggesting that it inhibits tmRNA activity directly.

115 cinating quality-control mechanisms involves tmRNA, also known as SsrA or 10Sa RNA.

116 high temperature because of the role of its tmRNA product in rescuing stalled ribosomes.

117 hemical studies suggest mechanisms that keep tmRNA from interrupting normal translation and target ri

118 In Caulobacter crescentus cells lacking tmRNA activity there is a delay in the initiation of DNA

119 li cells, but accumulates in mutants lacking tmRNA.

120 e developed two genetic selections that link tmRNA activity to cell death.

121 ion that supersedes a simple role of linking tmRNA to the ribosome, which the SmpB body alone could p

122 mponents of the trans-translation machinery, tmRNA, and its associated protein, SmpB, are essential f

123 The introduction of single-strand ACAs makes tmRNA highly susceptible to MazF cleavage.

124 on of an extended Mycoplasma pneumoniae (MP) tmRNA tag by the MP-Lon protease.

125 n can efficiently and selectively degrade MP-tmRNA-tagged proteins.

126 eractions between MP-Lon and the extended MP-tmRNA tag have co-evolved from pre-existing weaker inter

127 eal that the larger (27 amino acids long) MP-tmRNA tag contains multiple discrete signalling motifs f

128 ne encoding ssrA, a hybrid of tRNA and mRNA (tmRNA), which is involved in a trans-translation process

129 Inactivation of transfer mRNA (tmRNA) (encoded by ssrA), coupled with a multicopy kanam

130 cially by overproduction of a non-stop mRNA, tmRNA levels did not increase but tmRNA-mediated tagging

131 Using a mutant tmRNA that encodes a tag that does not lead to degradati

132 e identification of a large number of native tmRNA substrates.

133 egulation of these factors in the absence of tmRNA activity might be responsible for the delay in ini

134 In the absence of tmRNA tagging, truncated ArfA chains are released from t

135 Furthermore, analysis of tmRNA sequences from 442 bacteria showed that the discri

136 The initial binding of tmRNA and its subsequent accommodation into the ribosoma

137 The binding of tmRNA to the stalled ribosome is mediated by small prote

138 Here, we examine how binding of tmRNA-SmpB leads to proteolysis of RNase R.

139 ase protein, resulting in tighter binding of tmRNA-SmpB to the C-terminal region of exponential phase

140 s from acetylation which promotes binding of tmRNA-SmpB, two trans-translation factors, to its C-term

141 uggests that SmpB is a universal cofactor of tmRNA.

142 d by a ribonucleoprotein complex composed of tmRNA, a specialized RNA with properties of both a tRNA

143 protease responsible for the degradation of tmRNA-tagged proteins.

144 participates directly in the degradation of tmRNA-tagged proteins.

145 ATP-dependent protease in the degradation of tmRNA-tagged proteins.

146 stem is the major contributor to disposal of tmRNA-tagged proteins.

147 rowth but causes little if any disruption of tmRNA-mediated tagging.

148 oximately 13 to 15 angstroms of the entry of tmRNA into the ribosome.

149 that are likely to be a universal feature of tmRNA activity in eubacteria.

150 for proteins S1 and SmpB in the function of tmRNA.

151 The functions of tmRNA ensure that stalled ribosomes are rescued, the cau

152 ased in cells expressing very high levels of tmRNA and its binding protein SmpB, suggesting that reco

153 lon mutants accumulated excessive levels of tmRNA-tagged proteins.

154 spatially regulate RNAs, the localization of tmRNA was determined using fluorescence in situ hybridiz

155 ArfA (YhdL) is a mediator of tmRNA-independent ribosome rescue that is essential for

156 selection of the reading frame on the ORF of tmRNA.

157 d ribosome fractions only in the presence of tmRNA.

158 Additional biological roles of tmRNA include stress management and the regulation of tr

159 ributes information relevant to the study of tmRNA.

160 -Francisella tularensis chimeric variants of tmRNA and SmpB.

161 d the tagging activity of hybrid variants of tmRNA and the SmpB protein, in which the tmRNA ORF or th

162 polypeptide is transferred to the alanine on tmRNA, and translation switches from the original messag

163 ive message to a short open reading frame on tmRNA that tags the defective nascent peptide chain for

164 oth contribute to reading frame selection on tmRNA.

165 switches templates, resuming translation on tmRNA in the proper reading frame, remains unknown.

166 without interference from A-site cleavage or tmRNA activities.

167 The regulatory RNA SsrA (or tmRNA) has both tRNA and mRNA activities, relieving ribo

168 SsrA, or tmRNA, is a small RNA found in all bacteria that interve

169 SsrA, or tmRNA, is a small RNA that interacts with selected trans

170 usually occurs site-specifically at tRNA or tmRNA gene (together, tDNA) targets, catalyzed by tyrosi

171 Integration usually occurs within a tRNA or tmRNA gene, splitting the gene, yet sequences within the

172 teobacteria have one-piece tmRNA, a permuted tmRNA gene was found for Dechloromonas aromatica and clo

173 ereas most betaproteobacteria have one-piece tmRNA, a permuted tmRNA gene was found for Dechloromonas

174 main to that from a cyanobacterial two-piece tmRNA, but such transfer would not appear simple since t

175 cterial lineage with a loop-opened two-piece tmRNA.

176 down to 53 fmol of Streptococcus pneumoniae tmRNA, equivalent to approximately 3.16x10(7) CFU of bac

177 d 2) does SmpB pre-bind ribosomes to recruit tmRNA.

178 Nase R, and localization might also regulate tmRNA-SmpB interactions with ribosomes.

179 l SmpB-stalled ribosome interactions require tmRNA.

180 Cleavage does not require tmRNA, the ribosomal alarmone (p)ppGpp, or bacterial tox

181 on of the free form of RNase R also requires tmRNA-SmpB, but this process is independent of ribosomes

182 lexes in a process termed 'ribosome rescue.' tmRNA.SmpB specifically recognizes ribosomes that are pa

183 e recruitment of the transfer-messenger RNA (tmRNA) (SsrA) quality control system to distressed ribos

184 Transfer-messenger RNA (tmRNA) acts first as a tRNA and then as an mRNA template

185 The transfer-messenger RNA (tmRNA) and its partner protein SmpB act together in reso

186 mechanism involving transfer-messenger RNA (tmRNA) and its protein partner, SmpB.

187 anslation machinery, transfer-messenger RNA (tmRNA) and SmpB, that are responsible for the short half

188 protein B (SmpB) and transfer-messenger RNA (tmRNA) are the two known factors required for and dedica

189 Transfer-messenger RNA (tmRNA) enters stalled translational complexes and, with

190 ication of bacterial transfer-messenger RNA (tmRNA) is presented employing arrays of silicon photonic

191 bacteria, the hybrid transfer-messenger RNA (tmRNA) rescues ribosomes stalled on defective messenger

192 In eubacteria, the transfer-messenger RNA (tmRNA) system facilitates recycling of stalled ribosomes

193 sages are rescued by transfer-messenger RNA (tmRNA), a bifunctional molecule that acts as both a tran

194 mRNAs are rescued by transfer-messenger RNA (tmRNA), a dual-function molecule that contains a tRNA-li

195 Bacteria contain transfer-messenger RNA (tmRNA), a molecule that during trans-translation tags in

196 ialized mRNA, called transfer messenger RNA (tmRNA), to rescue such a stalled system.

197 ite component of the transfer messenger RNA (tmRNA)-mediated bacterial translational quality control

198 Transfer-messenger RNA (tmRNA)-SmpB specifically recognizes and resolves nonstop

199 omes is dependent on transfer-messenger RNA (tmRNA)-SmpB, nonstop mRNA, and the modified form of ribo

200 teolytic adaptor for transfer-messenger RNA (tmRNA)-tagged proteins, in Caulobacter crescentus.

201 o the translation of transfer-messenger RNA (tmRNA).

202 hought to facilitate transfer-messenger RNA (tmRNA).SmpB- mediated recycling of stalled ribosome comp

203 Transfer-messenger RNA (tmRNA, or SsrA), found in all eubacteria, has both trans

204 SsrA RNA (tmRNA), a regulatory RNA conserved in all bacteria, is c

205 l RNase P also processes precursor 4.5S RNA, tmRNA, 30S preribosomal RNA, and several reported protei

206 Analysis of select tmRNA variants revealed that the sequence composition an

207 n which tmRNA-SmpB is localized to sequester tmRNA from RNase R, and localization might also regulate

208 The tmRNA Website serves tmRNA sequences, alignments and feature annotations, and

209 witches from the original message to a short tmRNA open reading frame (ORF) that encodes a degradatio

210 like pattern that was separate from the SmpB-tmRNA complex.

211 The SmpB-tmRNA quality control system has evolved to solve proble

212 The SmpB-tmRNA-mediated trans-translation system has two well-est

213 We propose that a 1:1:1 complex of SmpB.tmRNA.EF-Tu(GTP) recognizes and binds a stalled ribosome

214 tly more labile than interaction of the SmpB.tmRNA complex with ribosomes.

215 though essential in a few bacterial species, tmRNA is nonessential in Escherichia coli and many other

216 Species specific tmRNA molecules are targeted by complementary DNA captur

217 onally tagged with a peptide encoded by ssrA/tmRNA (transfer-messenger RNA), which signals their degr

218 Strikingly, tmRNA-mediated SsrA peptide tagging of two proteins, rib

219 construct containing a hard-coded C-terminal tmRNA tag (GFP-SsrA) exhibited increased stability in lo

220 mical and structural data demonstrating that tmRNA is the high-affinity binding partner of SmpB.

221 These results indicate that tmRNA.SmpB activity is rate limited by mRNA cleavage, an

222 Together, these results indicate that tmRNA.SmpB does not suppress transient ribosome pauses,

223 urately replicates the in vivo process, that tmRNA-SmpB is not essential, but it stimulates binding o

224 We propose that tmRNA.SmpB binds to streptomycin-resistant rpsL ribosome

225 We show that tmRNA maintains a stable 'arc and fork' structure on the

226 em is targeted to ribosomes and suggest that tmRNA-tagging is used for both quality control and speci

227 The tmRNA alignment, available in a variety of formats, prov

228 The tmRNA pathway is thought to act only on ribosomes contai

229 The tmRNA sequences are aligned manually, assisted by comput

230 The tmRNA system orchestrates three key biological functions

231 The tmRNA system performs translational surveillance and rib

232 The tmRNA Website serves tmRNA sequences, alignments and fea

233 The tmRNA-SmpB system releases ribosomes stalled on truncate

234 o-formed complex containing ribosome and the tmRNA at the point where the TLD is accommodated into th

235 is compromised, A site mRNA cleavage and the tmRNA system provide a mechanism for reducing translatio

236 In bacteria, the tmRNA quality control system recycles these stalled ribo

237 r by facilitating an interaction between the tmRNA and another component of the translational apparat

238 dues that reside at the junction between the tmRNA-binding core and the C-terminal tail of SmpB play

239 ity with Escherichia coli SspB but binds the tmRNA tag in vitro and is required for optimal proteolys

240 led ribosomes in bacteria are rescued by the tmRNA system.

241 hly purified Lon preferentially degraded the tmRNA-tagged forms of proteins compared to the untagged

242 ghlighted the importance of establishing the tmRNA reading frame, and provided valuable clues into th

243 more significant bias in specificity for the tmRNA gene (ssrA) than for any type of tRNA gene.

244 pecificity, which showed strong bias for the tmRNA gene.

245 omplex with much improved definition for the tmRNA-SmpB complex, showing two SmpB molecules bound per

246 addition to its quality-control function the tmRNA system might also play a key regulatory role in ce

247 Furthermore, the tmRNA pathway is activated upon aza-C treatment in cells

248 Recent studies clarify how the tmRNA system is targeted to ribosomes and suggest that t

249 We found that mutants defective in the tmRNA translational quality control system are hypersens

250 y, the centroid of the RNA-like group is the tmRNA fold, a pseudoknot having both tRNA-like and mRNA-

251 Transcription of the tmRNA gene, however, was significantly up-regulated duri

252 proper positioning and establishment of the tmRNA open reading frame (ORF) as the surrogate template

253 hese data suggest that the engagement of the tmRNA ORF and the selection of the correct translation r

254 at an early stage after establishment of the tmRNA ORF as the surrogate mRNA template.

255 f the ultimate and penultimate codons of the tmRNA ORF play a crucial role in recruiting RNase R to r

256 Modifications of the tmRNA tag and use of higher-resolution mass spectrometry

257 ntegrity and the proteolytic function of the tmRNA tag are both crucial for normal growth and virulen

258 lly linked with the sequence upstream of the tmRNA template; both contribute to reading frame selecti

259 a high level of activity on the part of the tmRNA trans translation system.

260 r initiation of DNA replication, most of the tmRNA was degraded, and the remaining molecules were spr

261 ribosomes by facilitating recruitment of the tmRNA*SmpB ribosome rescue system.

262 her by stabilizing two distal regions of the tmRNA, or by facilitating an interaction between the tmR

263 ity map for the preaccommodated state of the tmRNA.SmpB.EF-Tu.70S ribosome complex with much improved

264 This process requires the tmRNA-binding and ribosome-binding cofactor SmpB, a beta

265 s Health Science Center at Tyler, Texas, the tmRNA database (tmRDB) is accessible at the URL http://p

266 These results argue that the tmRNA pathway clears stalled ribosome-mRNA complexes gen

267 Occupying the empty A site with its TLD, the tmRNA enters the ribosome with the help of elongation fa

268 t ArfA homologues are only deployed when the tmRNA system is incapacitated or overwhelmed by stalled

269 of tmRNA and the SmpB protein, in which the tmRNA ORF or the SmpB C-terminal tail was substituted wi

270 A site of the ribosome and explains why the tmRNA-SmpB system does not interfere with normal transla

271 pB sequences which are served along with the tmRNA sequence from the same organism.

272 rescue, the nascent chain is tagged with the tmRNA-encoded ssrA peptide, which promotes polypeptide d

273 rescue, the nascent chain is tagged with the tmRNA-encoded ssrA peptide, which targets the tagged pol

274 Within the tmRNA sequence itself, five nucleotides (U85AGUC) immedi

275 Lists of the tmRNAs and the corresponding tmRNA-encoded tag-peptides

276 Three-dimensional models of the tmRNAs and their associated proteins in PDB format give

277 This tmRNA activity results from sequestration of prolyl-tRNA

278 t ties the life of Escherichia coli cells to tmRNA activity.

279 The binding of S1 and its fragments to tmRNA and mRNA is positively cooperative, and the essent

280 ir ubiquitous colocalization with respect to tmRNA merits further examination.

281 t for the binding of ribosomal protein S1 to tmRNA.

282 translation complexes in a manner similar to tmRNA-SmpB recognition and directly hydrolyzes the pepti

283 d that SmpB, a protein that binds tightly to tmRNA, was colocalized with tmRNA in the helix-like patt

284 Mimicking a tRNA, tmRNA enters stalled ribosomes, adds Ala to the nascent

285 Correspondingly, two tmRNA pieces were identified, at approximately equal abu

286 The peptide tag encoded by wild-type tmRNA promotes rapid degradation of rescued proteins.

287 agging site, which is required for wild-type tmRNA tagging.

288 nces, an update raising the number of unique tmRNA sequences from 492 to 1716, and a database of SmpB

289 e stalled mRNA and resumes translation using tmRNA as a template, adding a short peptide tag that des

290 pid identification of different bacteria via tmRNA profiling.

291 However, the mechanism by which tmRNA can enter and move through the ribosome is unknown

292 These results suggest a model in which tmRNA-SmpB is localized to sequester tmRNA from RNase R,

293 nic (31%) or intragenic (28%) regions, while tmRNAs were targeted in 8% of the regions.

294 , a phenotype not previously associated with tmRNA activity.

295 Proteins known to be associated with tmRNA include SmpB, ribosomal protein S1, RNase R, and p

296 binds tightly to tmRNA, was colocalized with tmRNA in the helix-like pattern.

297 , a small protein that works in concert with tmRNA.

298 ite and may make base-specific contacts with tmRNA ligands.

299 0 S ribosomes SmpB partitions primarily with tmRNA rather than ribosomal subunits.

300 the importance of coupling proteolysis with tmRNA-mediated tagging and ribosome rescue.

301 ts mRNA template and resume translation with tmRNA itself as a template.