Genetius

The study demonstrates that the plastid chaperone CLPC2, but not its paralogue CLPC1, is essential for Arabidopsis responsiveness to microbial volatile compounds and for normal seed and seedling development. Loss of CLPC2 alters the chloroplast proteome, affecting proteins linked to growth, photosynthesis, and embryogenesis, while overexpression of CLPC2 mimics CLPC1 deficiency, highlighting distinct functional roles within the CLP protease complex.

The study integrates multi-omics data from six Sorghum bicolor accessions under field drought to link RNA covalent modifications (RCMs) with photosynthetic performance, identifying the enzyme SbDUS2 that produces dihydrouridine (DHU) on transcripts. Loss‑of‑function dus2 mutants in Arabidopsis thaliana reveal that DHU deficiency leads to hyperstability of photosynthesis‑related mRNAs, impairing germination, development, and stress‑induced CO2 assimilation. The authors propose DHU as a post‑transcriptional mark that promotes rapid mRNA turnover during abiotic stress, enhancing plant resilience.

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 authors established a live‑cell imaging platform that combines confocal microscopy of genetically encoded fluorescent protein biosensors with on‑stage illumination to monitor pH, MgATP²⁻, and NADH/NAD⁺ dynamics during dark‑light transitions in Arabidopsis mesophyll cells. They discovered that photosynthetic proton pumping triggers a stromal alkalinization wave extending to the cytosol and mitochondria, elevates MgATP²⁻ levels, and drives reduction of the NAD pool, with malate dehydrogenase mutants showing altered cytosolic redox even in darkness. This methodological advance enables high‑resolution mapping of photosynthesis‑linked energy physiology across cellular compartments.

The study compared photosynthetic performance and carbon metabolism in mature versus immature leaves of Arabidopsis thaliana accessions from different latitudes under standard and low‑temperature/high‑light conditions. Leaf‑specific measurements of Fv/Fm and CO2 assimilation revealed distinct acclimation capacities, and integration of carbohydrate and carboxylic‑acid profiles into a carbon balance model indicated that mature leaves help stabilize metabolism in younger tissue. The authors emphasize the importance of accounting for intra‑rosette heterogeneity to avoid misleading metabolic interpretations.

The study identifies the serine/threonine protein kinase CIPK14/SNRK3.15 as a regulator of sulfate‑deficiency responses in Arabidopsis thaliana seedlings, with mutants showing diminished early adaptive and later salvage responses under sulfur starvation. While snrk3.15 mutants exhibit no obvious phenotype under sufficient sulfur, the work provides a novel proteomic dataset comparing wild‑type and mutant seedlings under sulfur limitation.

The study profiled the Arabidopsis apoplastic proteome during pattern‑triggered immunity induced by the flg22 peptide, using apoplastic washing fluid with minimal cytoplasmic contamination followed by LC‑MS/MS. Results showed consistent PTI‑specific enrichment and depletion of peptides, a bias toward ectodomain peptides of receptor‑like kinases, and increased abundance of the exosome marker tetraspanin 8, indicating heightened exosome levels during PTI.