The interaction between tylophorine B and TMV RNA

Tylophorine B exhibits 60% inhibition against tobacco mosaic virus (TMV) at a concentration of 1.0 × 10−6 g/ml. In our study, high affinity for TMV RNA and assembly origin of TMV RNA (oriRNA) was revealed, accompanied by the conformational change of RNA. Considering that TMV assembly begins with the specific recognition by the coat protein aggregate of oriRNA, and that tylophorine B has favorable interaction with oriRNA, we speculate that tylophorine B likely exerts its virus inhibition by binding to oriRNA and interfering with virus assembly initiation. This work may shed light on the possible molecular inhibition mechanism against TMV by tylophorine B, and provide clues in rational design of sequence-specific RNA binding antivirus drugs.

Tobacco mosaic virus (TMV) inhibitor tylophorine B binds to TMV RNA in multiple binding sites with IC50 of 2.4 nM. It also binds to assembly origin of TMV RNA with one binding site of Kd of 9 nM. We speculate that tylophorine B likely exerts its virus inhibition by binding to assembly origin, and interfering with virus assembly initiation.Figure optionsDownload as PowerPoint slide