Structural basis for specific recognition of single-stranded RNA by Toll-like receptor 13. Academic Article uri icon

abstract

  • Toll-like receptors (TLRs) have crucial roles in innate immunity, functioning as pattern-recognition receptors. TLR13 recognizes a conserved sequence from bacterial 23S rRNA and then triggers an immune response. Here we report the crystal structure of the mouse TLR13 ectodomain bound by a 13-nt single-stranded (ss) RNA derived from 23S rRNA. The ssRNA induces TLR13 dimerization but assumes a stem-loop-like structure that is completely different from that in the bacterial ribosome but nevertheless is crucial for TLR13 recognition. Most of the RNA nucleotides are splayed out to make base-specific contacts with the concave surface of TLR13, and RNA-specific interactions are important to allow TLR13 to distinguish RNA from DNA. Interestingly, a viral-derived 16-nt ssRNA predicted to form a similar stem-loop-like structure also induces TLR13 activation. Together, our results reveal the structural mechanism of TLR13's sequence- and conformation-specific recognition of ssRNA.

published proceedings

  • Nat Struct Mol Biol

altmetric score

  • 4.75

author list (cited authors)

  • Song, W., Wang, J., Han, Z., Zhang, Y., Zhang, H., Wang, W., ... Chai, J.

citation count

  • 50

complete list of authors

  • Song, Wen||Wang, Jia||Han, Zhifu||Zhang, Yifan||Zhang, Heqiao||Wang, Weiguang||Chang, Junbiao||Xia, Bingshu||Fan, Shilong||Zhang, Dekai||Wang, Jiawei||Wang, Hong-Wei||Chai, Jijie

publication date

  • October 2015