The study uses an optogenetic ChannelRhodopsin 2 variant (XXM2.0) to generate defined cytosolic Ca²⁺ transients in Arabidopsis root cells, revealing that these Ca²⁺ signatures suppress auxin‑induced membrane depolarization, Ca²⁺ spikes, and auxin‑responsive transcription, leading to reversible inhibition of cell division and elongation. This demonstrates that optogenetically imposed Ca²⁺ signals act as dynamic regulators of auxin sensitivity in roots.
Regenerative agriculture effects on biomass, drought resilience and 14C-photosynthate allocation in wheat drilled into ley compared to disc or ploughed arable soil
Authors: Austen, N., Short, E., Tille, S., Johnson, I., Summers, R., Cameron, D. D., Leake, J. R.
Regenerative agriculture using a grass-clover ley increased wheat yields and macroaggregate stability despite reduced root biomass, but did not enhance soil carbon sequestration as measured by 14C retention. Drought further decreased photosynthate allocation to roots, especially in ley soils, while genotype effects on yield were minimal.
The study demonstrates that jasmonate (JA) enhances Arabidopsis thaliana responses to extracellular ATP (eATP) by upregulating the eATP receptor P2K1 and amplifying eATP‑induced cytosolic Ca²⁺ spikes and transcriptional reprogramming in a COI1‑dependent manner, whereas salicylic acid pretreatment suppresses these responses. These findings reveal a JA‑mediated priming mechanism that potentiates eATP signaling during stress.
The study examined how soil phosphorus and nitrogen availability influence wheat root-associated arbuscular mycorrhizal fungal (AMF) communities and the expression of mycorrhizal nutrient transporters. Field sampling across two years combined with controlled pot experiments showed that P and N jointly affect AMF colonisation, community composition (with Funneliformis dominance under high P), and regulation of phosphate, ammonium, and nitrate transporters. Integrating metabarcoding and RT‑qPCR provides a framework to assess AMF contributions to crop nutrition.
The study characterizes a plasma membrane-localized, calcium‑permeable force‑gated channel named Rapid Mechanically Activated (RMA) in plants, using patch‑clamp and pressure‑clamp to elucidate its rapid activation, inactivation, and irreversible adaptation upon repeated mechanical stimulation. Kinetic modeling shows the channel functions as a pass‑band filter for frequencies between 10 Hz and 1 kHz, supporting its role in transducing high‑frequency mechano‑stimuli such as insect vibrations.
The study compared aphid resistance and Barley Yellow Dwarf Virus (BYDV) transmission among three wheat varieties (G1, RGT Wolverine, RGT Illustrious). G1 emits the repellent 2‑tridecanone, restricts aphid phloem access, and shows reduced BYDV transmission, whereas RGT Wolverine limits systemic viral infection despite high transmission efficiency. The authors suggest breeding the two resistance mechanisms together for improved protection.
The study investigated whether wheat homoeologous genes actively compensate for each other when one copy acquires a premature termination codon (PTC) mutation. By analyzing mutagenised wheat lines, the authors found that only about 3% of cases exhibited upregulation of the unaffected homoeolog, indicating that widespread active transcriptional compensation is absent in wheat.
The study visualizes subcellular dynamics following activation of the NRC4 resistosome, showing that NRC4 enrichment at the plasma membrane triggers calcium influx, followed by sequential disruption of mitochondria, plastids, endoplasmic reticulum, and cytoskeleton, culminating in plasma membrane rupture and cell death. These observations define a temporally ordered cascade of organelle and membrane events that execute plant immune cell death.
The CATION CALCIUM EXCHANGER 4 (CCX4) regulates LRX1-related root hair development through Ca2+ homeostasis
Authors: Hou, X., Tortora, G., Herger, A., Buratti, S., Dobrev, P. I., Vaculikov, R., Lacek, J., Sotiropoulos, A. G., Kadler, G., Schaufelberger, M., Candeo, A., Bassi, A., Wicker, T., Costa, A., Ringli, C.
The study identified a suppressor mutation (sune42) in the Golgi-localized Ca2+ transporter CCX4 that alleviates the dominant‑negative root hair phenotype caused by the extensin‑less LRX1ΔE14 protein in Arabidopsis. Detailed Ca2+ imaging showed that LRX1ΔE14 disrupts tip‑focused cytoplasmic Ca2+ oscillations, a defect rescued by the sune42 mutation, highlighting the role of Golgi‑mediated Ca2+ homeostasis in root hair growth.
Overexpression of the wheat bHLH transcription factor TaPGS1 leads to increased flavonol accumulation in the seed coat, which disrupts polar auxin transport and causes localized auxin accumulation, delaying endosperm cellularization and increasing cell number, thereby enlarging grain size. Integrated metabolomic and transcriptomic analyses identified upregulated flavonol biosynthetic genes, revealing a regulatory module that links flavonol-mediated auxin distribution to seed development in wheat.