This study explores how the clubroot pathogen, Plasmodiophora brassicae, uses the effector PbGH3 to manipulate plant hormones and promote infection. Although structurally similar to auxin-conjugating enzymes, PbGH3 primarily targets salicylic acid (SA) metabolism. When expressed in Arabidopsis and canola, this protein alters root architecture, increasing root hair density and facilitating early colonization. The findings show that PbGH3 can partially compensate for the loss of the host protein PBS3, revealing a sophisticated strategy of molecular mimicry. By disrupting the balance between SA and jasmonates, the pathogen creates a hormonal environment that favors disease development in roots.

https://doi.org/10.64898/2026.03.10.710858