EPP1 is an ancestral component of the plant Common SymbiosisPathway
Authors: Rich, M. K., Vernie, T., Tiwari, M., Chauderon, L., Causse, J., Pellen, T., Boussaroque, A., Bianconi, M. E., Vandenbussche, M., Chambrier, P., Le Ru, A., Castel, B., Nagalla, S., Cullimore, J., Keller, J., Valdes-Lopez, O., Mbengue, M., Ane, J.-M., Delaux, P.-M.
The study identifies EPP1 as a fourth, conserved component of the ancestral common symbiosis pathway required for intracellular plant–microbe interactions, showing that its loss impairs arbuscular mycorrhizal colonization across diverse plant clades. EPP1 is phosphorylated by the plasma‑membrane receptor SYRMK, and this modification is essential for downstream activation of the nuclear kinase CCaMK, positioning EPP1 upstream in the signaling cascade.
The study investigated metabolic responses of kale (Brassica oleracea) grown under simulated microgravity using a 2-D clinostat versus normal gravity conditions. LC‑MS data were analyzed with multivariate tools such as PCA and volcano plots to identify gravity‑related metabolic adaptations and potential molecular markers for spaceflight crop health.
The study provides a comprehensive proteomic analysis of seed mitochondria from white lupin, revealing fully assembled OXPHOS complexes ready for immediate energy production upon imbibition. Quantitative mass‑spectrometry identified 1,162 mitochondrial proteins, highlighting tissue‑specific transporter and dehydrogenase profiles and dynamic remodeling during early germination, while many uncharacterized proteins suggest novel legume‑specific functions.
Light on its feet: Acclimation to high and low diurnal light is flexible in Chlamydomonas reinhardtii
Authors: Dupuis, S., Chastain, J. L., Han, G., Zhong, V., Gallaher, S. D., Nicora, C. D., Purvine, S. O., Lipton, M. S., Niyogi, K. K., Iwai, M., Merchant, S. S.
The study examined how prior light‑acclimation influences the fitness and rapid photoprotective reprogramming of Chlamydomonas during transitions between low and high diurnal light intensities. While high‑light‑acclimated cells struggled to grow and complete the cell cycle after shifting to low light, low‑light‑acclimated cells quickly remodeled thylakoid ultrastructure, enhanced photoprotective quenching, and altered photosystem protein levels, recovering chloroplast function within a single day. Transcriptomic and proteomic profiling revealed swift induction of stress‑response genes, indicating high flexibility in diurnal light acclimation.
The study introduces a native‑condition method combining cell fractionation and immuno‑isolation to purify autophagic compartments from Arabidopsis, followed by proteomic and lipidomic characterisation of the isolated phagophore membranes. Proteomic profiling identified candidate proteins linked to autophagy, membrane remodeling, vesicular trafficking and lipid metabolism, while lipidomics revealed a predominance of glycerophospholipids, especially phosphatidylcholine and phosphatidylglycerol, defining the unique composition of plant phagophores.
The study demonstrates that ABI5‑Binding Proteins (AFPs) interact with multiple components of the core ABA signaling pathway and serve as substrates for SnRK2 kinases and PP2C phosphatases, linking them to MAP kinases and 14‑3‑3 proteins. Phosphorylation of AFP2, promoted by ABA, stabilizes the protein and influences its subcellular localization, thereby modulating its ability to inhibit ABA responses during seed germination.
Mycotoxin-driven proteome remodeling reveals limited activation of Triticum aestivum responses to emerging chemotypes integrated with fungal modulation of ergosterols
Authors: Ramezanpour, S., Alijanimamaghani, N., McAlister, J. A., Hooker, D., Geddes-McAlister, J.
The study used comparative proteomics to examine how the emerging 15ADON/3ANX chemotype of Fusarium graminearum affects protein expression in both wheat and the fungus. It identified a core wheat proteome altered by infection, chemotype‑specific wheat proteins, and fungal proteins linked to virulence and ergosterol biosynthesis, revealing distinct molecular responses influencing disease severity.
The study examined three fruit morphotypes of the desert shrub Haloxylon ammodendron, revealing distinct germination performances under salt and drought stress. Proteomic analysis identified 721 differentially expressed proteins, particularly between the YP and PP morphotypes, linking stress‑responsive protein abundance to rapid germination in YP and delayed germination in PP as contrasting adaptive strategies. The findings suggest that fruit polymorphism facilitates niche differentiation and informs germplasm selection for desert restoration.
The study tracked molecular changes in plastoglobules and thylakoids of Zea mays B73 during heat stress and recovery, revealing increased plastoglobule size, number, and adjacent lipid droplets over time. Proteomic and lipidomic analyses uncovered up‑regulation of specific plastoglobule proteins and alterations in triacylglycerol, plastoquinone derivatives, and phytol esters, suggesting roles in membrane remodeling and oxidative defense. These insights highlight plastoglobule‑associated pathways as potential targets for enhancing heat resilience in maize.
The study identifies the RNA‑binding protein AtG3BP1 as a phosphorylation target of MAPKs MPK3, MPK4, and MPK6 at Ser257 in Arabidopsis thaliana and shows that this modification promotes susceptibility to bacterial pathogens, suppresses ROS accumulation and salicylic acid biosynthesis, and maintains stomatal opening. Phospho‑mimic and phospho‑dead mutants reveal that phosphorylation stabilizes AtG3BP1 by preventing proteasomal degradation, highlighting a novel post‑translational control layer in plant immunity.