Summary information and primary citation
- PDB-id
- 2qbz; DSSR-derived features in text and JSON formats
- Class
- RNA
- Method
- X-ray (2.6 Å)
- Summary
- Structure of the m-box riboswitch aptamer domain
- Reference
- Dann III CE, Wakeman CA, Sieling CL, Baker SC, Irnov I, Winkler WC (2007): "Structure and mechanism of a metal-sensing regulatory RNA." Cell(Cambridge,Mass.), 130, 878-892. doi: 10.1016/j.cell.2007.06.051.
- Abstract
- Organisms maintain the correct balance of intracellular metals primarily through metal-sensing proteins that control transport and storage of the target ion(s). Here, we reveal the basis of metal sensing and genetic control by a metalloregulatory RNA. Our data demonstrate that a previously uncharacterized orphan riboswitch, renamed the "M-box," is a divalent metal-sensing RNA involved in Mg(2+) homeostasis. A combination of genetic, biochemical, and biophysical techniques demonstrate that Mg(2+) induces a compacted tertiary architecture for M-box RNAs that regulates the accessibility of nucleotides involved in genetic control. Molecular details are provided by crystallographic structure determination of a Mg(2+)-bound M-box RNA. Given the distribution of this RNA element, it may constitute a common mode for bacterial metal ion regulation, and its discovery suggests the possibility of additional RNA-based metal sensors in modern and primordial organisms.
