sbRNA

sbRNA
Conserved secondary structure of nematode sbRNA
Identifiers
Symbol sbRNA
Other data
RNA type Gene
Domain(s) Caenorhabditis

sbRNA (stem-bulge RNA) is a family of non-coding RNA first discovered in Caenorhabditis elegans. It was identified during a full transcriptome screen of the C. elegans cDNA library.[1] Subsequent experimentation characterised sbRNA as having conserved 5' and 3' internal motifs which form a long paired stem which is interrupted with a bulge.[2]

Contents

Expression

sbRNAs have variable expression patterns during development. They are most highly expressed in adult worms, dauer larvae and following heat shock.[1] A systematic knockout analysis using RNAi found no phenotype for the knockout of two sbRNAs in C. elegans,[3] however the efficiency of RNAi on ncRNA has been questioned.[4] sbRNAs contain immunoglobulin in their protein fibers to maintain rigidity, however they are at risk of infection from malfunctioning ribosomes.

sbRNAs share common promoter elements consisting of a TATA box and a proximal sequence element (PSE B box), though only one of these are required for transcription.[5] As the transcript is uncapped and polyuridylated, it is though to be transcribed by RNA polymerase III.[6]

Y RNA homology

An sbRNA, CeN134 was reported as a candidate homologue to the vertebrate Y RNA during a kingdom-wide search.[7] Further investigation found a homologous secondary structure with a conserved helical regions and a common UUAUC loop motif.[6]

The function of sbRNAs may therefore be similar to that of vertebrate Y RNAs, namely acting as part of the Ro-RNA particle to control RNA quality[8] and playing a role in chromosomal replication.[9] Deletion of sbRNA does not prevent chromosome replication in C. elegans, but this may be a result of other sbRNAs substituting missing elements (as in human Y RNA). This theory also explains why RNAi studies failed to detect a phenotype for knocked out sbRNAs.[6]

See also

References

  1. ^ a b Deng W, Zhu X, Skogerbø G, et al. (January 2006). "Organization of the Caenorhabditis elegans small non-coding transcriptome: genomic features, biogenesis, and expression". Genome Res. 16 (1): 20–9. doi:10.1101/gr.4139206. PMC 1356125. PMID 16344563. http://www.genome.org/cgi/pmidlookup?view=long&pmid=16344563. Retrieved 2010-08-03. 
  2. ^ Aftab MN, He H, Skogerbø G, Chen R (2008). "Microarray analysis of ncRNA expression patterns in Caenorhabditis elegans after RNAi against snoRNA associated proteins". BMC Genomics 9: 278. doi:10.1186/1471-2164-9-278. PMC 2442092. PMID 18547420. http://www.biomedcentral.com/1471-2164/9/278. Retrieved 2010-08-03. 
  3. ^ Kamath RS, Fraser AG, Dong Y, et al. (January 2003). "Systematic functional analysis of the Caenorhabditis elegans genome using RNAi". Nature 421 (6920): 231–7. doi:10.1038/nature01278. PMID 12529635. 
  4. ^ Ploner A, Ploner C, Lukasser M, Niederegger H, Hüttenhofer A (October 2009). "Methodological obstacles in knocking down small noncoding RNAs". RNA 15 (10): 1797–804. doi:10.1261/rna.1740009. PMC 2743047. PMID 19690100. http://www.rnajournal.org/cgi/pmidlookup?view=long&pmid=19690100. Retrieved 2010-08-03. 
  5. ^ Li T, He H, Wang Y, Zheng H, Skogerbø G, Chen R (2008). "In vivo analysis of Caenorhabditis elegans noncoding RNA promoter motifs". BMC Mol. Biol. 9: 71. doi:10.1186/1471-2199-9-71. PMC 2527325. PMID 18680611. http://www.biomedcentral.com/1471-2199/9/71. Retrieved 2010-08-03. 
  6. ^ a b c Boria I, Gruber AR, Tanzer A, et al. (April 2010). "Nematode sbRNAs: homologs of vertebrate Y RNAs". J. Mol. Evol. 70 (4): 346–58. doi:10.1007/s00239-010-9332-4. PMID 20349053. 
  7. ^ Perreault J, Perreault JP, Boire G (August 2007). "Ro-associated Y RNAs in metazoans: evolution and diversification". Mol. Biol. Evol. 24 (8): 1678–89. doi:10.1093/molbev/msm084. PMID 17470436. http://mbe.oxfordjournals.org/cgi/pmidlookup?view=long&pmid=17470436. Retrieved 2010-08-03. 
  8. ^ Stein AJ, Fuchs G, Fu C, Wolin SL, Reinisch KM (May 2005). "Structural insights into RNA quality control: the Ro autoantigen binds misfolded RNAs via its central cavity". Cell 121 (4): 529–39. doi:10.1016/j.cell.2005.03.009. PMC 1769319. PMID 15907467. http://linkinghub.elsevier.com/retrieve/pii/S0092-8674(05)00242-4. Retrieved 2010-08-03. 
  9. ^ Christov CP, Gardiner TJ, Szüts D, Krude T (September 2006). "Functional requirement of noncoding Y RNAs for human chromosomal DNA replication". Mol. Cell. Biol. 26 (18): 6993–7004. doi:10.1128/MCB.01060-06. PMC 1592862. PMID 16943439. http://mcb.asm.org/cgi/pmidlookup?view=long&pmid=16943439. Retrieved 2010-08-03. 

Further reading