SAM-IV riboswitch
Encyclopedia
SAM-IV riboswitches are a kind of riboswitch
that specifically binds S-adenosylmethionine (SAM) , a cofactor used in many methylation reactions. Originally identified by bioinformatics
, SAM-IV riboswitches are largely confined to the Actinomycetales
, an order of Bacteria
. Conserved features of SAM-IV riboswitch and experiments imply that they probably share a similar SAM-binding site to another class of SAM-binding riboswitches called SAM-I riboswitches. However, the scaffolds of these two types of riboswitch appear to be quite distinct.
Riboswitch
In molecular biology, a riboswitch is a part of an mRNA molecule that can directly bind a small target molecule, and whose binding of the target affects the gene's activity. Thus, an mRNA that contains a riboswitch is directly involved in regulating its own activity, in response to the...
that specifically binds S-adenosylmethionine (SAM) , a cofactor used in many methylation reactions. Originally identified by bioinformatics
Bioinformatics
Bioinformatics is the application of computer science and information technology to the field of biology and medicine. Bioinformatics deals with algorithms, databases and information systems, web technologies, artificial intelligence and soft computing, information and computation theory, software...
, SAM-IV riboswitches are largely confined to the Actinomycetales
Actinomycetales
Actinomycetales is an order of Actinobacteria. They are very diverse and contain a variety of subdivisions as well as yet unclassified isolates. This is mainly because some genera are very difficult to classify because of a highly niche-dependent phenotype...
, an order of Bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
. Conserved features of SAM-IV riboswitch and experiments imply that they probably share a similar SAM-binding site to another class of SAM-binding riboswitches called SAM-I riboswitches. However, the scaffolds of these two types of riboswitch appear to be quite distinct.
See also
- SAM-I riboswitchSAM riboswitch (S box leader)The SAM riboswitch is found upstream of a number of genes which code for proteins involved in methionine or cysteine biosynthesis in Gram-positive bacteria. Two SAM riboswitches in Bacillus subtilis that were experimentally studied act at the level of transcription termination control...
- SAM-II riboswitch
- SAM-III riboswitchSMK box riboswitchThe SMKbox riboswitch is a RNA element that regulates gene expression in bacteria. The SMK box riboswitch is found in the 5' UTR of the MetK gene in lactic acid bacteria...
- SAM-V riboswitchSAM-V riboswitchSAM-V riboswitch is the fifth known riboswitch to bind S-adenosyl methionine . It was first discovered in the marine organism Candidatus Pelagibacter ubique and can also be found in marine metagenomes. SAM-V features a similar consensus sequence and secondary structure as the binding site of SAM-II...