terC RNA | |
---|---|
Identifiers | |
Symbol | terC |
Rfam | RF03067 |
Other data | |
RNA type | Cis-reg; |
SO | SO:0005836 |
PDB structures | PDBe |
The terC RNA motif is a conserved RNA structure that was discovered by bioinformatics. [1] terC motif RNAs are found in Pseudomonadota, within the sub-lineages Alphaproteobacteria and Pseudomonadales.
terC motif RNAs likely function as cis-regulatory elements, in view of their positions upstream of protein-coding genes. Indeed, the RNAs are upstream of multiple genes that encode non-homologous proteins. If all examples of the RNA were upstream of homologous genes, there is the possibility that the RNAs were conserved in that position simply by inheritance. The non-homology of the genes downstream of terC RNAs makes this scenario less likely.
When considering the conserved protein domains contained in proteins that are encoded by terC-regulated genes, the most frequent are classified as TIGR03717 and TIGR03718, according to the Conserved domain database. Both TIGR03717 and TIGR03718 are homologous with the membrane-bound protein known as TerC. TerC proteins are implicated in tellurium resistance. [2]
A separate conserved RNA, originally known as the YybP-ykoY leader, is now known to function as a manganese-sensing riboswitch. Genes regulated by these manganese riboswitches very frequently encode proteins similar to TerC. In view of this association, it was proposed [1] that terC RNAs might also function as riboswitches that sense an ion similar to manganese. Experimental confirmation of this hypothesis is lacking. However, the conserved domain known as "COG3809" is also commonly regulated by terC RNAs as well as manganese riboswitches, providing another possible link between these conserved RNA structures.
The yybP-ykoY leader RNA element was originally discovered in E. coli during a large scale screen and was named SraF. This family was later found to exist upstream of related families of protein genes in many bacteria, including the yybP and ykoY genes in B. subtilis. The specific functions of these proteins are unknown, but this structured RNA element may be involved in their genetic regulation as a riboswitch. The yybP-ykoY element was later proposed to be manganese-responsive after another associated family of genes, YebN/MntP, was shown to encode Mn2+ efflux pumps in several bacteria. Genetic data and a crystal structure confirmed that yybp-ykoY is a manganese riboswitch that directly binds Mn2+
The Downstream-peptide motif refers to a conserved RNA structure identified by bioinformatics in the cyanobacterial genera Synechococcus and Prochlorococcus and one phage that infects such bacteria. It was also detected in marine samples of DNA from uncultivated bacteria, which are presumably other species of cyanobacteria.
The yjdF RNA motif is a conserved RNA structure identified using bioinformatics. Most yjdF RNAs are located in bacteria classified within the phylum Bacillota. A yjdF RNA is found in the presumed 5' untranslated region of the yjdF gene in Bacillus subtilis, and almost all yjdF RNAs are found in the 5' UTRs of homologs of this gene. The function of the yjdF gene is unknown, but the protein that it is predicted to encode is classified by the Pfam Database as DUF2992.
The DUF1646 RNA motif is a conserved RNA structure that was discovered by bioinformatics. One of the two DUF1646 RNAs in Enterococcus faecalis was independently detected by term-seq. Data from both discoveries suggest that DUF1646 RNAs are cis-regulatory RNAss, and that at least some DUF1646 RNAs use Rho-independent transcription terminators as their mechanism to regulate gene expression.
The COG2908 RNA motif is a conserved RNA structure that was discovered by bioinformatics. COG2908 motif RNAs are found in genomic sequences extracted from fresh water environments. They have not, as of 2018, been detected in any classified organism.
The DUF805 RNA motif is a conserved RNA structure that was discovered by bioinformatics. The motif is subdivided into the DUF805 motif and the DUF805b motif, which have similar, but distinct secondary structures. Together, these motifs are found in Bacteroidota, Chlorobiota, and Pseudomonadota.
The folE RNA motif, now known as the THF-II riboswitch, is a conserved RNA structure that was discovered by bioinformatics. folE motifs are found in Alphaproteobacteria.
The FTHFS RNA motif is a conserved RNA structure that was discovered by bioinformatics. FTHFS motifs are found in metagenomic sequences derived from samples of the human gut.
The GA-cis RNA motif is a conserved RNA structure that was discovered by bioinformatics. GA-cis motif RNAs are found in one species classified within the phylum Bacillota: specifically, there are 9 predicted copies in Coprocuccus eutactus ATCC 27759.
The hya RNA motif is a conserved RNA structure that was discovered by bioinformatics. hya motif RNAs are found in Actinomycetota.
The Latescibacteria, OD1, OP11, TM7 RNA motif is a conserved RNA structure that was discovered by bioinformatics. LOOT motif RNAs are found in multiple bacterial phyla that have only recently been discovered, and are currently not well understood: Latescibacteria, OD1/Parcubacteria, OP11 AND TM7. In some cases, no specific organism has been isolated in the relevant phylum, but the existence of the bacterial phylum is known only through analysis of metagenomic sequences. Curiously, the LOOT motif is not known in any phylum that has been studied for a long time.
malK RNA motifs are conserved RNA structures that were discovered by bioinformatics. They are defined by being consistently located upstream of malK genes, which encode an ATPase that is used by transporters whose ligand is likely a kind of sugar. Most of these genes are annotated either as transporting maltose or glycerol-3-phosphate, however the substrate of the transporters associated with malK motif RNAs has not been experimentally determined. All known types of malK RNA motif are generally located nearby to the Shine-Dalgarno sequence of the downstream gene.
The MDR-NUDIX RNA motif is a conserved RNA structure that was discovered by bioinformatics. The MDR-NUDIX motif is found in the poorly studied phylum TM7.
The nhaA-I RNA motif is a conserved RNA structure that was discovered by bioinformatics. nhaA-I motif RNAs are found in Acidobacteriota, alpha-, beta- and Gammaproteobacteria, Verrucomicrobiota and the tentative phylum NC10.
The NLPC-P60 RNA motif is a conserved RNA structure that was discovered by bioinformatics. NLPC-P60 motif RNAs are found in Streptomyces.
The NMT1 RNA motif is a conserved RNA structure that was discovered by bioinformatics. NMT1 motif RNAs are found in Pseudomonadota. There is also one NMT1 RNA in each of Bacteroidota and Actinomycetota, but these appear to be the result of recent horizontal gene transfer or sequence contamination before or during genome sequencing
The pemK RNA motif is a conserved RNA structure that was discovered by bioinformatics. pemK motif RNAs are found in organisms within the phylum Bacillota, and is very widespread in this phylum.
The PGK RNA motif is a conserved RNA structure that was discovered by bioinformatics. PGK motif RNAs are found in metagenomic sequences isolated from the gastrointestinal tract of mammals. PGK RNAs have not yet been detected in a classified organism.
The sul1 RNA motif is a conserved RNA structure that was discovered by bioinformatics. Energetically stable tetraloops often occur in this motif. sul1 motif RNAs are found in Alphaproteobacteria.
The uup RNA motif is a conserved RNA structure that was discovered by bioinformatics. uup motif RNAs are found in Bacillota and Gammaproteobacteria.