DSSR-PyMOL cartoon-block schematics: PDB entry 3r2c

PDB-id

3r2c; DSSR-derived features in text and JSON formats

Class

transcription-RNA

Method

X-ray (1.902 Å)

Summary

Crystal structure of antitermination factors nusb and nuse in complex with boxa RNA

Reference

Stagno JR, Altieri AS, Bubunenko M, Tarasov SG, Li J, Court DL, Byrd RA, Ji X (2011): "Structural basis for RNA recognition by NusB and NusE in the initiation of transcription antitermination." Nucleic Acids Res., 39, 7803-7815. doi: 10.1093/nar/gkr418.

Abstract

Processive transcription antitermination requires the assembly of the complete antitermination complex, which is initiated by the formation of the ternary NusB-NusE-BoxA RNA complex. We have elucidated the crystal structure of this complex, demonstrating that the BoxA RNA is composed of 8 nt that are recognized by the NusB-NusE heterodimer. Functional biologic and biophysical data support the structural observations and establish the relative significance of key protein-protein and protein-RNA interactions. Further crystallographic investigation of a NusB-NusE-dsRNA complex reveals a heretofore unobserved dsRNA binding site contiguous with the BoxA binding site. We propose that the observed dsRNA represents BoxB RNA, as both single-stranded BoxA and double-stranded BoxB components are present in the classical lambda antitermination site. Combining these data with known interactions amongst antitermination factors suggests a specific model for the assembly of the complete antitermination complex.