Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “RNA, Small Cytoplasmic”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Bacillus subtilis histone-like protein, HBsu, is an integral component of a SRP-like particle that can bind the Alu domain of small cytoplasmic RNA.

Small cytoplasmic RNA (scRNA) is metabolically stable and abundant in Bacillus subtilis cells. Consisting of 271 nucleotides, it is structurally homologous to mammalian signal recognition particle RNA. In contrast to 4.5 S RNA of Escherichia coli, B. subtilis scRNA contains an Alu domain in addition to the evolutionarily conserved S domain. In this study, we show that a 10-kDa protein in B. subtilis cell extracts has scRNA binding activity at the Alu domain. The in vitro binding selectivity of the 10-kDa protein shows that it recognizes the higher structure of the Alu domain of scRNA caused by five consecutive complementary sequences in the two loops. Purification and subsequent analyses demonstrated that the 10-kDa protein is HBsu, which was originally identified as a member of the histone-like protein family. By constructing a HBsu-deficient B. subtilis mutant, we showed that HBsu is essential for normal growth. Immunoprecipitating cell lysates using anti-HBsu antibody yielded scRNA. Moreover, the co-precipitation of HBsu with (His)6-tagged Ffh depended on the presence of scRNA, suggesting that HBsu, Ffh, and scRNA make a ternary complex and that scRNA serves as a functional unit for binding. These results demonstrated that HBsu is the third component of a signal recognition particle-like particle in B. subtilis that can bind the Alu domain of scRNA.

Amino Acid Sequence↗

Depletion of Bacillus subtilis histone-like protein, HBsu, causes defective protein translocation and induces upregulation of small cytoplasmic RNA.

Small cytoplasmic RNA (scRNA) is a metabolically stable homologue of mammalian SRP RNA that contains an Alu-like domain. The Bacillus subtilis histone-like protein HBsu can bind this domain. We demonstrate here that repressing the level of HBsu results in slow growth and the accumulation of precursor of beta-lactamase fusion proteins having the signal sequence of alkaline protease, penicillin binding protein 5* (PBP5*) or CGTase. The degree of the translocation defect varied among the various signal sequences tested. A pulse-chase experiment showed that processing the alpha-amylase signal sequence is significantly inhibited in HBsu-depleted cells. Northern blot analysis indicated that repressing the HBsu gene induces scRNA upregulation, indicating that the defective translocation of presecretory proteins is not due to a reduced scRNA level. The data presented here suggest that HBsu plays a pivotal role in SRP function rather than simply stabilizing the other SRP components such as scRNA.

Bacillus subtilis↗

Small cytoplasmic RNA of Bacillus subtilis: functional relationship with human signal recognition particle 7S RNA and Escherichia coli 4.5S RNA.

Small cytoplasmic RNA (scRNA; 271 nucleotides) is an abundant and stable RNA of the gram-positive bacterium Bacillus subtilis. To investigate the function of scRNA in B. subtilis cells, we developed a strain that is dependent on isopropyl-beta-D-thiogalactopyranoside for scRNA synthesis by fusing the chromosomal scr locus with the spac-1 promoter by homologous recombination. Depletion of the inducer leads to a loss of scRNA synthesis, defects in protein synthesis and production of alpha-amylase and beta-lactamase, and eventual cell death. The loss of the scRNA gene in B. subtilis can be complemented by the introduction of human signal recognition particle 7S RNA, which is considered to be involved in protein transport, or Escherichia coli 4.5S RNA. These results provide further evidence for a functional relationship between B. subtilis scRNA, human signal recognition particle 7S RNA, and E. coli 4.5S RNA.

Bacterial Proteins↗

Phylogenetic and biochemical evidence for a secondary structure model of a small cytoplasmic RNA from Bacilli.

Small cytoplasmic RNA (scRNA; 271 nucleotides) is an abundant, stable RNA identified in the Gram-positive eubacterium Bacillus subtilis. Several findings suggest an important role of scRNA in protein biosynthesis: it shares structural and biochemical features with the Escherichia coli 4.5S RNA (114 nucleotides), a molecule known to be involved in this process, and it can complement the essential function of 4.5S RNA in vivo. The common apical hairpin motif of scRNA and 4.5S RNA also exists in eukaryotic 7SL RNA, the RNA component of the signal recognition particle. To elucidate the higher-order structure of scRNA, we have combined a phylogenetic approach with a biochemical one. The sequence of scRNA from a thermophilic relative of B. subtilis, Bacillus stearothermophilus, was determined and compared with the B. subtilis scRNA. In addition, the solution structure of B. stearothermophilus scRNA was probed with single- and double-strand-specific nucleases. Both types of analysis support a secondary structure model for scRNA that strongly resembles 4.5S RNA and respective parts of 7SL RNA. The results provide further evidence for the suggestion of a functional relationship between these RNAs.

Bacillus subtilis↗

Bacillus subtilis RNase III cleaves both 5'- and 3'-sites of the small cytoplasmic RNA precursor.

Bacillus subtilis small cytoplasmic RNA (scRNA) is a member of the signal recognition particle RNA family. It is transcribed as a 354-nucleotide primary transcript and processed to a 271-nucleotide mature scRNA. In the precursor, the 5'- and 3'-flanking regions form a stable double-stranded structure based on their complementary sequence. This structure is similar to those of substrates for the double-stranded RNA processing enzyme, RNase III. The B. subtilis enzyme that has similar activity to Escherichia coli RNase III has been purified and is designated Bs-RNase III. Recently, B. subtilis rncS has been shown to encode Bs-RNase III (Wang, W., and Bechhofer, D. H. (1997) J. Bacteriol. 179, 7379-7385). We show here that Bs-RNase III and the purified His-tagged product of rncS cleave pre-scRNA at both 5'- and 3'-sites to produce an intermediate scRNA (scRNA-275), although processing at the 3'-site is less efficient. The 5'-end of scRNA-275 was identical to that of the mature scRNA, whereas it contains four excess nucleotides at the 3'-end. Bs-RNase III cleavage yields a two-base 3'-overhang, which is consistent with the manner in which E. coli RNase III cleaves. We also show that truncation of the rncS gene affected processing, and significant amounts of an intermediate scRNA (scRNA-275) were found to accumulate in the rncS-truncated mutant. It is concluded that Bs-RNase III is an enzyme that processes pre-scRNA.

Bacillus subtilis↗

Small cytoplasmic RNA associated with polyadenylated RNA is involved in the hormonal regulation of gene expression.

The fraction of small RNA (sacc-RNA) associated with cytoplasmic rat liver poly(A)+ RNA by non-covalent, possibly complementary, interactions has been isolated and studied. Fingerprint analysis and Northern blot hybridization data reveal that the specific changes occur in the population of sacc-RNA in response to glucocorticoid treatment. The close similarity of the oligonucleotide composition of sacc-RNA and RNA-component of small nuclear RNP-acceptor of glucocorticoid hormones has been found. The hypothesis of the involvement of the small RNA in the hormonal regulation of posttranscriptional stages of gene expression in the cytoplasm has been put forward.

Animals↗

The most abundant small cytoplasmic RNA of Saccharomyces cerevisiae has an important function required for normal cell growth.

The most abundant RNA visible between 5.8S and 18S rRNA on an ethidium bromide-stained gel of total Saccharomyces cerevisiae RNA has an apparent size of about 600 nucleotides. By purifying the band and using it as a probe to screen a genomic library, we isolated and sequenced the unique gene for this RNA. The transcribed sequence, determined to be 519 nucleotides long, contains elements typical of RNA polymerase III transcription. The RNA is predominantly cytoplasmic, so we called it small cytoplasmic RNA 1 (scR1). ScR1 is neither 3'-polyadenylated nor 5'-trimethylguanosine capped. We constructed a null mutation of the gene by deleting 252 base pairs from the transcribed region. Haploid strains carrying the scr1-delta lesion grew very slowly, segregated cytoplasmic petites [( rho-]) at high frequency, and showed signs of aberrant cell division. A secondary structure model for scR1 shows some of the conserved features of the signal recognition particle 7SL RNAs.

Base Sequence↗

Transcription and processing of Bacillus subtilis small cytoplasmic RNA.

The 271 nucleotides long scRNA (small cytoplasmic RNA) from Bacillus subtilis is structurally related to the Escherichia coli 4.5 S RNA (114 nucleotides), an essential molecule supposed to be involved in protein biosynthesis, but it possesses an additional moiety completely missing in the E. coli 4.5 S RNA. Both RNAs share a conserved hairpin with the eukaryotic 7SL RNAs, which mediate protein translocation as part of the signal recognition particle (SRP). We have cloned and sequenced the entire scRNA gene region from B. subtilis and have studied transcription and processing of the scRNA in B. subtilis by nuclease S1 mapping. This analysis revealed the scRNA gene to constitute a monofunctional transcription unit, expressed from a single promoter to a rho-independent terminator, yielding a precursor which extends the mature scRNA by approximately 40 nucleotides at both ends. Processing of the scRNA apparently involves only two endonucleolytic cuts and occurs first at the 5' end.

Bacillus subtilis↗

Characterization of a 17 kDa protein gene upstream from the small cytoplasmic RNA gene of Bacillus subtilis.

The Bacillus subtilis small cytoplasmic RNA (scRNA) is the structural homologue of both the RNA component of the eukaryotic signal recognition particle (SRP) and the Escherichia coli 4.5S RNA, and it can complement the essential function of the latter RNA in vivo. In the course of characterization of the single-copy scRNA gene locus (scr) we identified an open reading frame, termed ORF17, upstream from scr that encodes an acidic 17 kDa protein of unknown function. This analysis involved DNA sequencing, monitoring expression of transcriptional and translational ORF17-cat and ORF17-lacZ fusions, respectively, and purification and sequencing of the ORF17-lacZ fusion protein. Apparently, transcription of ORF17 proceeds into scr. A small portion of the 17 kDa protein shows homology to deoxycytidylate (DCMP) deaminase of bacteriophagphage T2, but no similarity exists to the sequenced SRP-polypeptides or any other known protein sequences.

Amino Acid Sequence↗

Depletion of small cytoplasmic RNA confers fusidic-acid resistance on Bacillus subtilis.

Bacillus subtilis small cytoplasmic RNA (scRNA) is a member of a signal recognition particle (SRP)-like RNA family. To analyze the function of scRNA in protein synthesis, a B. subtilis strain SC201NA was constructed in which the expression of intact scRNA is regulated by an IPTG-inducible promoter. In this strain, depletion of scRNA leads to deficient translation and sporulation as well as morphological changes. In addition, the growth of SC201NA in the absence of IPTG became fusidic-acid resistant. The acquisition of fusidic-acid resistant phenotype by depletion of scRNA suggested that scRNA is associated with elongation factor G (EF-G) in the translation process.

Bacillus subtilis↗

Structural requirements of Bacillus subtilis small cytoplasmic RNA for cell growth, sporulation, and extracellular enzyme production.

Bacillus subtilis small cytoplasmic RNA (scRNA; 271 nucleotides) is a member of the signal recognition particle (SRP) RNA family, which has evolutionarily conserved primary and secondary structures. The scRNA consists of three domains corresponding to domains I, II, and IV of human SRP 7S RNA. To identify the structural determinants required for its function, we constructed mutant scRNAs in which individual domains or conserved nucleotides were deleted, and their importance was assayed in vivo. The results demonstrated that domain IV of scRNA is necessary to maintain cell viability. On the other hand, domains I and II were not essential for vegetative growth but were preferentially required for the RNA to achieve its active structure, and assembled ribonucleoprotein between Ffh and scRNA is required for sporulation to proceed. This view is highly consistent with the fact that the presence of domains I and II is restricted to sporeforming B. subtilis scRNA among eubacterial SRP RNA-like RNAs.

Bacillus subtilis↗

Molecular cloning and phylogenetic analysis of the small cytoplasmic RNA from Listeria monocytogenes.

A molecular cloning strategy has been designed to isolate the gene that encodes the small cytoplasmic RNA (scRNA) component of bacterial signal recognition particles. Using this strategy a putative Listeria monocytogenes scRNA lambda gt11 recombinant clone was isolated. A previously described complementation assay developed to genetically select functional homologues of 4.5S RNA and scRNA of bacteria confirmed that the lambda gt11 recombinant clone isolated encoded for the scRNA from L. monocytogenes. A secondary structure for this scRNA is proposed and a phylogenetic comparison of the 276 base L. monocytogenes scRNA with previously characterised Gram-positive bacterial scRNAs is also presented.

Base Sequence↗

Identification of a region of Bacillus subtilis Ffh, a homologue of mammalian SRP54 protein, that is essential for binding to small cytoplasmic RNA.

Bacillus subtilis Ffh and scRNA are homologues of mammalian SRP54 and SRP RNA, respectively, which are components of the eukaryotic signal recognition particle (SRP). Ffh (446 amino acids) interacts with scRNA to form a stable complex in vivo. Here, we identified an RNA-binding domain of Ffh. The results obtained using a series of deletion mutants show that amino acid positions 364 to 432 in the C-terminal region of Ffh correlates with its ability to bind RNA. The amino acid sequence of this region is well conserved among members of the SRP54 protein family. This sequence contains two hydrophobic regions (h2, 364 to 391, and h3, 416 to 435), separated by the positively charged amino acid motif, 398RRKRIAKGSG407. Among the basic amino acid residues in this region, Arg-401 was essential for binding to scRNA, but Arg-399 and Lys-400 were not. The co-existence of Arg-398 and Lys-404 was necessary for the same affinity as wild type Ffh. The two glycine residues of the 405GSG407 were also essential. MH23 peptide (91 amino acids) encompassing from 356 to 446, consisting of h2-RRKRIAKGSG-h3, bound scRNA with the same affinity as wild type Ffh, whereas a 24-amino acid synthetic peptide 392DIINASRRKRIAKGSGTSVQEVNR415 did not. The region containing two hydrophobic segments separated by the positively charged motif is the minimal requirement of Ffh for RNA binding.

Amino Acid Sequence↗

The 3' UTR of human MnSOD mRNA hybridizes to a small cytoplasmic RNA and inhibits gene expression.

Human MnSOD localizes to the mitochondria and plays a key protective role by detoxifying oxygen free radicals. The MnSOD mRNA 3' UTR contains a 280-bp region (Alu-like element or Alu-E) that shows high homology to human Alu and 7SL sequences. MnSOD 3' UTR probes hybridize to a specific cytoplasmic RNA species of approximately 300 nucleotides. This antisense RNA is most likely 7SL RNA based on its size, ubiquitousness, high levels, and lack of inducibility. Hybridization of this small RNA to the MnSOD 3' UTR may modulate posttranscriptional MnSOD gene expression. This regulation could occur by several means including inhibition of translation and mRNA destabilization. Regulation at the level of translational initiation does not seem to occur as MnSOD mRNA containing the Alu-E is efficiently bound by ribosomes. To test the role of the MnSOD 3' UTR, and in particular the Alu-E in gene expression, luciferase reporter gene constructs were made containing various regions of the MnSOD 3' UTR including the Alu-E. These constructs were transfected into human A549 lung carcinoma cells and luciferase activity was measured. Reporter constructs containing the MnSOD 3' UTR and the Alu-E repress luciferase activity. Taken together, these results suggest that naturally occurring antisense RNA may bind MnSOD mRNA and repress its expression. These results also suggest that other mRNAs containing Alu elements may be similarly repressed.

3' Untranslated Regions↗

Small cytoplasmic RNA (scRNA) gene from Clostridium perfringens can replace the gene for the Bacillus subtilis scRNA in both growth and sporulation.

Small cytoplasmic RNA (scRNA) is a member of an evolutionarily conserved signal-recognition-particle-like RNA family. Using a DNA fragment of Bacillus subtilis scRNA gene as a probe, we cloned and characterized a Clostridium perfringens gene encoding the scRNA. Mapping the 5' and 3' ends of scRNA revealed that C. perfringens scRNA consists of 269 nucleotides: the sequence has about 70% primary sequence homology with B. subtilis scRNA. The predicted secondary structure appeared to be similar to that of B. subtilis scRNA, indicating that there are domains I and II in C. perfringens scRNA, in addition to domain IV. Functional analysis showed that C. perfringens scRNA could compensate for vegetative growth and allow the formation of heat-resistant spores in an scRNA-depleted B. subtilis strain, whereas Escherichia coli 4.5S RNA could not maintain sporulation. Since both E. coli 4.5S RNA and C. perfringens scRNA have the same binding specificity to B. subtilis Ffh protein, the difference in complementation activity reflects the function of domains I and II.

Amino Acid Sequence↗

The Bacillus subtilis SRP54 homologue, Ffh, has an intrinsic GTPase activity and forms a ribonucleoprotein complex with small cytoplasmic RNA in vivo.

B. subtilis Ffh is a homologue of SRP54, which is one component of the mammalian signal recognition particle. B. subtilis Ffh was expressed in E. coli as a derivative with a hexa histidine tag at the COOH terminus and purified to near homogeneity. The purified Ffh had intrinsic GTPase activity as predicted from its amino acid sequence. Using antiserum against Ffh, we also demonstrated that B. subtilis Ffh forms a complex with scRNA which is a B subtilis homologue of the RNA component of SRP in vivo, and that half of the resulting complex is found in the peripheral fraction of the cytoplasmic membrane where the initiation of protein translocation occurs. These findings provide evidence of a ribonucleoprotein complex in B. subtilis, reminiscent of SRP.

Animals↗

Reinitiation of synthesis of small cytoplasmic RNA species K and L in isolated HeLa cell nuclei in vitro.

Isolated HeLa cell nuclei were used to synthesize low molecular weight RNA species in-vitro. The labelled RNA released from the nuclei during the incubation mainly consists of 5S RNA, pre-tRNA and small cytoplasmic RNA species K and L. All these low molecular weight RNA species are synthesized by RNA polymerase C (or III). The polyanion heparin was applied to study the reinitiation of these RNA molecules in-vitro. A comparison of the kinetics of RNA synthesis in the absence and in the presence of this inhibitor demonstrates a highly efficient in-vitro reinitiation of scRNA species K and L as well as 5S and pre-tRNA by RNA polymerase C. These results indicate a general competence of this enzyme to catalyze the de-novo formation of specific gene products in-vitro.

Cell Nucleus↗

The Bacillus subtilis small cytoplasmic RNA gene and 'dnaX' map near the chromosomal replication origin.

The Bacillus subtilis small cytoplasmic RNA (scRNA) has an important, although not yet defined function in protein biosynthesis. Here we describe the mapping of the single copy scRNA gene and the flanking homolog to dnaZX of Escherichia coli, termed 'dnaX'. The scRNA gene region of a B. subtilis wild-type strain was marked with a cat gene and mapped by scoring chromosomal cotransformation rates of various mutant strains to chloramphenicol resistance and loss of the mutant phenotypes, respectively. This analysis, together with an EcoRI map comparison, places the scRNA gene and dnaX in the vicinity of recM near the replication origin region of B. subtilis.

Bacillus subtilis↗