Sensing metabolic signals with nascent RNA transcripts: the T box and S box riboswitches as paradigms.
Recent studies in a variety of bacterial systems have revealed a number of regulatory systems in which the 5' region of a gene plays a key role in regulation of the downstream coding sequences. These RNA regions act in cis to determine if the full-length transcript will be synthesized or if the coding sequence(s) will be translated. Each class of system includes an RNA element whose structure is modulated in response to a specific regulatory signal, and the signals measured can include small molecules, small RNAs (including tRNA), and physical parameters such as temperature. Multiple sets of genes can be regulated by a particular mechanism, and multiple systems of this type, each of which responds to a specific signal, can be present in a single organism. In addition, different classes of RNA elements can be found that respond to a particular signal, indicating the existence of multiple alternate solutions to the same regulatory problem. The T box and S box systems, which respond to uncharged tRNA and S-adenosylmethionine (SAM), respectively, provide paradigms of two systems of this type.
Henkin
T M
TM
Department of Microbiology and The RNA Group, The Ohio State University, Columbus, Ohio 43210, USA.
Grundy
F J
FJ
D000596:Amino Acids / Q000378:metabolism; D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001483:Base Sequence; D015964:Gene Expression Regulation, Bacterial; D008954:Models, Biological; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D014176:Protein Biosynthesis; D012329:RNA, Bacterial / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D015398:Signal Transduction; D014158:Transcription, Genetic
D000596:Amino Acids; D001426:Bacterial Proteins; D012329:RNA, Bacterial