Back

A conserved small RNA-generating gene cluster undergoes sequence diversification and contributes to plant immunity

Feng, L.; Hou, Y.; Toghani, A.; Wang, Z.; Tang, B.; Atkinson, N.; Li, H.; Qiao, Y.; Wang, Y.; Hua, J.; Zhai, J.; Ma, W.

2025-07-21 plant biology
10.1101/2025.07.20.665670 bioRxiv
Show abstract

Small RNA-mediated gene silencing contributes to plant immunity. The secondary small interfering RNA (siRNA) pathway promotes defense by silencing target genes in invading fungal and oomycete pathogens. Many secondary siRNAs derive from transcripts potentially encoding pentatricopeptide repeat (PPR) proteins. Here, we report that siRNA production is an ancient function of an evolutionarily conserved clade of PPR genes that undergo extensive within-species diversification. In Arabidopsis thaliana, siRNA-source PPRs are physically clustered in one locus on Chromosome 1. These sequences are diversified through gene duplication followed by sequence diversification as well as accumulation of high-impact variations including pseudogenization. This diversity leads to the accumulation of a diverse PPR-siRNA pool, consistent with an engagement in a co-evolutionary arms race with the pathogens. This study defines siRNA-producing PPRs as a family of defense genes and highlights the potential of PPR-siRNA-based engineering for enhancing broad-spectrum disease resistance.

Matching journals

The top 6 journals account for 50% of the predicted probability mass.

50% of probability mass above

"Similar papers" are the closest papers from that journal in the model's embedding space. They show what the match is built on, but the ranking comes mostly from a classifier over the whole training set, not from these examples alone.