Thermotolerant pollen tube growth is controlled by RALF signaling.
Authors: Althiab Almasaud, R., Ouonkap Yimga, S. V., Ingram, J., Oseguera, Y., Alkassem Alosman, M., Travis, C., Henry, A., Medina, M., Oulhen, N., Wessel, G. M., Delong, A., Pease, J., DaSilva, N., Johnson, M.
The study investigates the molecular basis of heat‑tolerant pollen tube growth in tomato (Solanum lycopersicum) by comparing thermotolerant and sensitive cultivars. Using live imaging, transcriptomics, proteomics, and genetics, the authors identified the Rapid Alkalinization Factor (RALF) signaling pathway as a key regulator of pollen tube integrity under high temperature, with loss of a specific RALF peptide enhancing tube integrity in a thermotolerant cultivar.
The study examined nitrogen use strategies in the model alga Chlamydomonas reinhardtii by comparing growth on ammonium, nitrate, and urea, finding similar molar nitrogen utilization efficiency under saturating conditions. Rapid nitrogen uptake and storage were demonstrated through pulse experiments, and source‑specific transcriptome analysis revealed distinct regulation of assimilation pathways and transporters, supporting a model of flexible nitrogen acquisition and storage.
The study investigates how maternal environmental conditions, specifically temperature and light intensity, influence seed longevity in eight Arabidopsis thaliana natural accessions. Seeds developed under higher temperature (27 °C) and high light showed increased longevity, with transcriptome analysis of the Bor-4 accession revealing dynamic changes in stored mRNAs, including upregulation of antioxidant defenses and raffinose family oligosaccharides. These findings highlight the genotype‑dependent modulation of seed traits by the maternal environment.
Discovery of tomato UDP-glucosyltransferases involved in bioactive jasmonate homeostasis using limited proteolysis-coupled mass spectrometry
Authors: Venegas-Molina, J., Mohnike, L., Selma Garcia, S., Janssens, H., Colembie, R., Kimpe, I., Jaramillo-Madrid, A. C., Lacchini, E., Winne, J. M., Van Damme, P., Feussner, I., Goossens, A., Sola, K.
The study applied limited proteolysis‑coupled mass spectrometry (LiP‑MS) to map JA‑protein interactions, validating known JA binders and uncovering novel candidates, including several UDP‑glucuronosyltransferases (UGTs). Functional omics, biochemical, enzymatic, and structural analyses demonstrated that two tomato UGTs glucosylate jasmonic acid, revealing a previously missing step in JA catabolism.
The study demonstrates that limonene, a natural essential‑oil component, strongly inhibits Fusarium oxysporum, the causal agent of potato dry rot, by impairing colony growth, hyphal morphology, spore viability, membrane integrity, and transcription/translation processes, as well as disrupting ion homeostasis. Combined treatments reveal additive effects with mancozeb and synergistic effects with hymexazol, highlighting limonene's potential as an eco‑friendly bio‑fungicide for potato disease management.
The study assessed the impact of adding mammalian growth factors and cytokines to transformation media on CRISPR‑Cas9–mediated genome editing in six tomato (Solanum lycopersicum) accessions with varying regeneration capacities. Over three years, supplementation with these factors significantly increased regeneration rates and the production of stable secondary transgenic lines, especially in recalcitrant genotypes.
The researchers created tomato lines overexpressing the autophagy gene SlATG8f and evaluated their performance under high-temperature stress. qRT‑PCR and physiological measurements revealed that SlATG8f overexpression enhances expression of autophagy‑related and heat‑shock protein genes, accelerates fruit ripening, and improves fruit quality under heat stress.
Proteomic comparison of mock‑ and potato spindle tuber viroid‑infected tomato revealed a broad down‑regulation of nucleoporins and nuclear transport receptors, leading to impaired nuclear import of the immune regulator NPR1. Overexpression of NPR1 or treatment with a salicylic‑acid analog restored defense and reduced PSTVd infection, highlighting nuclear transport repression as a key vulnerability in plant immunity against viroids.
The study isolated an endophytic Pseudomonas aeruginosa strain (SPT08) from tomato cotyledon seedlings that suppressed the wilt pathogen Ralstonia pseudosolanacearum and promoted plant growth, increasing height by 20% and root biomass by 60%. GFP labeling confirmed endophytic colonization, and genomic analysis revealed multiple secretion systems and secondary‑metabolite gene clusters associated with biocontrol and growth‑promoting traits.
The study investigates the evolutionary shift from archegonial to embryo‑sac reproduction by analyzing transcriptomes of Ginkgo reproductive organs and related species. It reveals that the angiosperm pollen‑tube guidance module MYB98‑CRP‑ECS is active in mature Ginkgo archegonia and that, while egg cell transcription is conserved, changes in the fate of other female gametophyte cells drove the transition, providing a molecular framework for this major reproductive evolution.