The study demonstrates that in Arabidopsis, the receptor-like kinase CRK2 phosphorylates and retains QSK1 at the plasma membrane under normal conditions, preventing excess callose deposition at plasmodesmata. Osmotic stress leads to dephosphorylation of QSK1, allowing its relocalization to plasmodesmata where it promotes stress‑induced callose accumulation, while CRK2 later moves to plasmodesmata to negatively regulate this deposition, revealing a dynamic gating mechanism.

The study reveals that Arabidopsis CRK2 phosphorylates the callose synthases CALS1 and CALS3, influencing callose deposition at plasmodesmata and thereby affecting phloem loading and source‑to‑sink transport. Loss of CRK2 leads to starch accumulation in older leaves, a phenotype rescued by introducing functional CALS1 or CALS3 alleles, indicating that CRK2, CALS1, and CALS3 jointly regulate growth and development through control of intercellular transport.

The study created transgenic Arabidopsis lines enabling inducible plasmodesmal closure via an overactive CALLOSE SYNTHASE3 allele (icals3m) and the C‑terminal domain of PDLP1, independent of pathogen signals. Induced closure triggered stress‑responsive gene expression, elevated salicylic acid levels, and enhanced resistance to Pseudomonas syringae, while also causing starch accumulation, reduced growth, and increased susceptibility to Botrytis cinerea, indicating that plasmodesmal closure itself can activate immune signaling.

The study examined how polyploidy, hybridization, and incomplete lineage sorting affect phylogenetic reconstructions in the genus Packera, evaluating several published paralog‑processing pipelines. Results showed that the choice of orthology and paralog handling methods markedly altered tree topology, time‑calibrated phylogenies, biogeographic histories, and detection of ancient reticulation, underscoring the need for careful methodological selection alongside comprehensive taxon sampling.

The study investigated chloroplast retrograde signals that regulate plasmodesmata-mediated intercellular trafficking, identifying heme from the tetrapyrrole biosynthetic pathway as a key modulator. Using Arabidopsis thaliana mutants and Nicotiana benthamiana gene silencing, the authors pinpointed heme‑responsive genes that likely alter plasmodesmata function, linking chloroplast signaling to coordinated plant development and resource allocation.

Foliar application of Trichoderma harzianum cell‑free culture filtrates (CF) increased fruit yield, root growth, and photosynthesis in a commercial tomato cultivar under prolonged water deficit in a Mediterranean greenhouse. Integrated physiological, metabolite, and transcriptomic analyses revealed that CF mitigated drought‑induced changes, suppressing about half of water‑stress responsive genes, thereby reducing the plant’s transcriptional sensitivity to water scarcity.

The authors demonstrate that the WAVE/SCAR complex component BRK1 localizes to plasmodesmata and primary pit fields in Arabidopsis, using a BRK1‑YFP reporter line. BRK1 enrichment coincides with regions of reduced propidium iodide staining and colocalizes with aniline blue‑stained callose, suggesting that ARP2/3‑dependent actin branching contributes to plasmodesmata permeability regulation alongside formin‑mediated linear actin.

The study examined the evolution of plasmodesmata density across an evolutionary gradient of Flaveria species ranging from C3 to C4 photosynthetic types using electron microscopy. It identified two discrete, stepwise increases in plasmodesmata frequency, with a marked enrichment at the mesophyll‑bundle sheath interface in C4-like and C4 species, suggesting that heightened cell‑to‑cell connectivity underpins the development of C4 metabolism.

The study functionally characterizes three tomato CNR/FWL proteins (SlFWL2, SlFWL4, SlFWL5) and demonstrates that SlFWL5 localizes to plasmodesmata, where it regulates leaf size and morphology by promoting cell expansion likely through cell‑to‑cell communication. Gain‑ and loss‑of‑function transgenic tomato lines reveal that SlFWL5 is a key regulator of organ growth via modulation of plasmodesmatal signaling.

The study examined transcriptomic responses of the tropical seagrass Halophila stipulacea from a pristine and an impacted site under single and combined thermal and excess nutrient stress in mesocosms. Combined stress caused greater gene reprogramming than individual stresses, with thermal effects dominating and the impacted population showing reduced plasticity but higher resilience. Core stress‑response genes were identified as potential early field indicators of environmental stress.