Cooperative binding of effectors by an allosteric ribozyme
AUTOR(ES)
Jose, Antony M.
FONTE
Oxford University Press
RESUMO
An allosteric ribozyme that requires two different effectors to induce catalysis was created using modular rational design. This ribozyme construct comprises five conjoined RNA modules that operate in concert as an obligate FMN- and theophylline-dependent molecular switch. When both effectors are present, this ‘binary’ RNA switch self-cleaves with a rate enhancement of ∼300-fold over the rate observed in the absence of effectors. Kinetic and structural studies implicate a switching mechanism wherein FMN binding induces formation of the active ribozyme conformation. However, the binding site for FMN is rendered inactive unless theophylline first binds to its corresponding site and reorganizes the RNA structure. This example of cooperative binding between allosteric effectors reveals a level of structural and functional complexity for RNA that is similar to that observed with allosteric proteins.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=31269Documentos Relacionados
- Cooperative and anticooperative binding to a ribozyme.
- Mechanism for allosteric inhibition of an ATP-sensitive ribozyme.
- Bidirectional effectors of a group I intron ribozyme.
- Allosteric regulation of the glucose:H+ symporter of Lactobacillus brevis: cooperative binding of glucose and HPr(ser-P).
- Allosteric regulation of a ribozyme activity through ligand-induced conformational change.