Searching across hundreds of databases

Our searching services are busy right now. Your search will reload in five seconds.

Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

Thiamine derivatives bind messenger RNAs directly to regulate bacterial gene expression.

Nature | Oct 31, 2002

Although proteins fulfil most of the requirements that biology has for structural and functional components such as enzymes and receptors, RNA can also serve in these capacities. For example, RNA has sufficient structural plasticity to form ribozyme and receptor elements that exhibit considerable enzymatic power and binding specificity. Moreover, these activities can be combined to create allosteric ribozymes that are modulated by effector molecules. It has also been proposed that certain messenger RNAs might use allosteric mechanisms to mediate regulatory responses depending on specific metabolites. We report here that mRNAs encoding enzymes involved in thiamine (vitamin B(1)) biosynthesis in Escherichia coli can bind thiamine or its pyrophosphate derivative without the need for protein cofactors. The mRNA-effector complex adopts a distinct structure that sequesters the ribosome-binding site and leads to a reduction in gene expression. This metabolite-sensing regulatory system provides an example of a 'riboswitch' whose evolutionary origin might pre-date the emergence of proteins.

Pubmed ID: 12410317 RIS Download

Mesh terms: Allosteric Regulation | Allosteric Site | Bacterial Proteins | Base Sequence | Caenorhabditis elegans Proteins | Escherichia coli | Escherichia coli Proteins | Gene Expression Regulation, Bacterial | Genes, Bacterial | Molecular Sequence Data | Mutation | Nucleic Acid Conformation | Protein Biosynthesis | RNA, Bacterial | RNA, Messenger | Receptors, Neuropeptide Y | Regulatory Sequences, Ribonucleic Acid | Ribosomes | Substrate Specificity | Thiamine | Thiamine Pyrophosphate