A wheat lncRNA-encoded peptide promotes autophagy and targets viral NIb for degradation to confer antiviral resistance

Long noncoding RNAs (lncRNAs) are increasingly recognized as a source of functional peptides involved in plant development and immunity, yet little is known about whether lncRNA-encoded peptides participate in antiviral defence. By transcriptome analysis with peptide-coding potential prediction, we identify lncRNA19864, which is highly expressed in wheat yellow mosaic virus (WYMV)-resistant cultivars and encodes a 39-amino-acid peptide, TaLEP1. Genetic manipulation of TaLEP1 expression showed that TaLEP1 as a positive regulator of wheat resistance to WYMV. Mechanistically, TaLEP1 forms oligomers and interacts with both the host autophagy factor TaATG18a and the viral replicase NIb, thereby facilitating NIb recruitment to autophagosomes for degradation. Disruption of TaLEP1 oligomerization or TaATG18a function impaired NIb degradation and compromised TaLEP1-mediated antiviral resistance. Notably, TaLEP1 also confers resistance to other Potyviridae members, including Turnip mosaic virus (TuMV) and Soybean mosaic virus (SMV), by similarly targeting their NIb proteins for degradation. Accordingly, lncRNA-encoded peptide is involved in plant antiviral immunity. Our results offer a potential strategy for engineering broad-spectrum virus resistance in crops.