Bacteria use processing body condensates to attenuate host translation during infection
Authors: Gonzalez-Fuente, M., Schulz, N., Abdrakhmanov, A., Izzati, G., Zhu, S., Langin, G., Gouguet, P., Franz-Wachtel, M., Macek, B., Hafren, A., Dagdas, Y., Üstün, S.
The study reveals that the bacterial pathogen Pseudomonas syringae suppresses host plant translation by targeting processing bodies (P‑bodies) through two liquid-like effectors, linking this repression to the ER stress response. It further demonstrates that autophagic clearance of P‑bodies is essential for balancing translationally active and inactive mRNAs, uncovering new connections among translation, ER stress, and autophagy during plant immunity.
The study investigates the role of the Arabidopsis transcription factor AtMYB93 in sulfur (S) signaling and root development, revealing that AtMYB93 mutants exhibit altered expression of S transport and metabolism genes and increased shoot S levels, while tomato plants overexpressing SlMYB93 show reduced shoot S. Transcriptomic profiling, elemental analysis, and promoter activity assays indicate that AtMYB93 contributes to root responses to S deprivation, though functional redundancy masks clear phenotypic effects on lateral and adventitious root formation.
The study investigates the Arabidopsis ribosomal protein RPS6A and its role in auxin‑related root growth, revealing that rps6a mutants display shortened primary roots, fewer lateral roots, and defective vasculature that are not rescued by exogenous auxin. Cell biological observations and global transcriptome profiling show weakened auxin signaling and reduced levels of PIN auxin transporters in the mutant, indicating a non‑canonical function of the ribosomal subunit in auxin pathways.
A biparental Vicia faba mapping population was screened under glasshouse conditions for resistance to a mixture of Fusarium avenaceum and Fusarium oxysporum, revealing several families with moderate to high resistance. Using the Vfaba_v2 Axiom SNP array, a high-density linkage map of 6,755 SNPs was constructed, enabling the identification of a major QTL on linkage group 4 associated with partial resistance to foot and root rot.
The study investigated melatonin priming on methylglyoxal detoxification and autophagy during PEG‑induced drought stress in seed germination of drought‑sensitive (L‑799) and tolerant (Suraj) upland cotton. Melatonin increased endogenous melatonin, reduced MGO and AGEs, up‑regulated glyoxalase enzymes and autophagy markers, and improved cell viability in the sensitive variety, while the tolerant variety showed limited response.
The study investigated unexpected leaf spot symptoms in Psa3‑resistant kiwifruit (Actinidia) germplasm, finding that Psa3 was detectable by qPCR and metabarcoding despite poor culturing. Metabarcoding revealed distinct bacterial community shifts in lesions versus healthy tissue, and whole‑genome sequencing identified diverse Pseudomonas spp. that, while not individually more pathogenic, could enhance Psa3 growth, suggesting pathogenic consortia on resistant hosts.
Lack of AtMC1 catalytic activity triggers autoimmunity dependent on NLR stability
Authors: Salguero-Linares, J., Armengot, L., Ayet, J., Ruiz-Solani, N., Saile, S., Salas-Gomez, M., Fernandez, E., Denolf, L., Navarrete, F., Krumbach, J., Kaiser, M., Stael, S., Van Breusegem, F., Gevaert, K., Kaschani, F., petersen, m., El Kasmi, F., Valls, M., Coll, N. S.
The study demonstrates that loss of Arabidopsis metacaspase 1 (AtMC1) triggers autoimmunity reliant on downstream NLR and PRR signaling, and that overexpressing a catalytically dead AtMC1 exacerbates this effect. Overexpression of the E3 ligase SNIPER1 restores normal immunity, suggesting that AtMC1 regulates NLR protein turnover, possibly via autophagic degradation of the inactive protein.