SAM-IV riboswitch

SAM-IV riboswitches are a kind of riboswitch that specifically binds S-adenosylmethionine (SAM),^[1] a cofactor used in many methylation reactions. Originally identified by bioinformatics,^[2] 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. The structural relationship between these riboswitch types has been studied.^[3][4]

S-adenosyl methionine (SAM) riboswitch,
Predicted secondary structure and sequence conservation of SAM-IV
Identifiers
Symbol	SAM-IV
Rfam	RF00634 CL00012
Other data
RNA type	Cis-reg; riboswitch
Domain(s)	Bacteria
SO	SO:0005836
PDB structures	PDBe

See also

• SAM-I riboswitch
• SAM-II riboswitch
• SAM-III riboswitch
• SAM-V riboswitch
• SAM-VI riboswitch