A moss N-Acetyltransferase-MAPK protein controls 2D to 3D developmental transition via acetylation and phosphorylation changes
Authors: de Luxan Hernandez, C., Ammitsoe, T. J., Kanne, J. V., Stanimirovic, S., Roux, M., Weeks, Z., Schutzbier, M., Dürnberger, G., Roitinger, E., Zhang, L., Spadiut, O., Ishikawa, M., Hasebe, M., Moody, L., Dagdas, Y., Rodriguez, E., Petersen, M.
The study identifies a moss‑specific fusion protein, Rosetta NATD‑MAPK 1 (RAK1), that combines a MAPK domain with an N‑acetyltransferase and demonstrates that its acetyltransferase activity is enhanced upon MAPK activation. Knockout of RAK1 impairs the 2D‑to‑3D developmental transition in Physcomitrium patens, and mass‑spectrometry reveals associated changes in acetylation and phosphorylation linked to metabolic reprogramming.
Comparative multi-omics profiling of Gossypium hirsutum and Gossypium barbadense fibers at high temporal resolution reveals key differences in polysaccharide composition and associated glycosyltransferases
Authors: Swaminathan, S., Lee, Y., Grover, C. E., DeTemple, M. F., Mugisha, A. S., Sichterman, L. E., Yang, P., Xie, J., Wendel, J. F., Szymanski, D. B., Zabotina, O. A.
The study performed daily large-scale glycome, transcriptome, and proteome profiling of developing fibers from the two cultivated cotton species, Gossypium barbadense and G. hirsutum, across primary and secondary cell wall stages. It identified delayed cellulose accumulation and distinct compositions of xyloglucans, homogalacturonans, rhamnogalacturonan‑I, and heteroxylans in G. barbadense, along with higher expression of specific glycosyltransferases and expansins, suggesting these molecular differences underlie the superior fiber length and strength of G. barbadense.
The study evaluated how acute heat stress affects early-stage rice seedlings, identifying a critical temperature threshold that impairs growth. Transcriptomic profiling of shoots and roots revealed ethylene‑responsive factors (ERFs) as central regulators, with ethylene and jasmonic acid acting upstream, and pre‑treatment with these hormones mitigated heat damage. These findings highlight ERF‑hormone interaction networks as targets for improving rice heat resilience.
The study examined how white lupin (Lupinus albus) cotyledons mobilize nitrogen and minerals during early seedling growth under nitrogen‑deficient conditions, revealing that 60 % of stored proteins degrade within eight days and are redirected to support development. Proteomic analyses showed dynamic shifts in nutrient transport, amino acid metabolism, and stress responses, and premature cotyledon removal markedly impaired growth, highlighting the cotyledon's essential role in nutrient supply and transient photosynthetic activity.
Using the Euphorbia peplus genome, the authors performed organ‑specific transcriptomic profiling of the cyathium and combined it with gene phylogenies and dN/dS analysis to investigate floral‑development gene families. They found distinct SEP1 paralog expression, lack of E‑class gene duplications typical of other pseudanthia, and divergent expression patterns for CRC, UFO, LFY, AP3, and PI, suggesting unique developmental pathways in Euphorbia.
The study reveals that a conserved serine adjacent to the catalytic glutamate in TIR domains is essential for NAD+‑cleaving activity, and that phosphorylation of this serine by plant calcium‑dependent protein kinases (CPKs) or mammalian kinases (CAMK2D, TBK1) inhibits the activity, thereby preventing growth repression and cell death. This phosphorylation-based mechanism provides a universal means to balance growth and immune defense across species.
The study shows that heatwaves impair the ability of apple (Malus domestica) to mount ASM‑induced immunity against fire blight and apple scab, leading to a loss of protective gene expression. Transcriptomic analysis revealed a broad suppression of ASM‑regulated defense and other biological processes under high temperature, identifying thermo‑sensitive resistance and susceptibility marker genes. The findings highlight that elevated temperature both weakens plant defenses and creates a more favorable environment for pathogens.
The study identifies RAF24, a B4 Raf-like MAPKKK, as a novel regulator of flowering time in Arabidopsis, demonstrating that RAF24 controls the phosphorylation of the ubiquitin ligase HUB2 via SnRK2 kinases, thereby modulating H2Bub1 levels. Phospho‑mimetic and phospho‑ablative HUB2 mutants confirm that phosphorylation at S314 is critical for proper flowering timing.
The study identified a major QTL (qDTH3) on chromosome 3 responsible for a 7‑10‑day earlier heading phenotype in the rice line SM93, using QTL‑seq, KASP genotyping, association mapping, and transcriptomic analysis to fine‑map the locus to a 2.53 Mb region and pinpoint candidate genes. SNP markers linked to these genes were proposed as tools for breeding early‑maturing, climate‑resilient rice varieties.
The study compares transcriptional, proteomic, and metabolomic responses of wild‑type Arabidopsis and a cyp71A27 mutant to a plant‑growth‑promoting Pseudomonas fluorescens strain and a pathogenic Burkholderia glumeae strain, revealing distinct reprogramming and an unexpected signaling role for the non‑canonical P450 CYP71A27. Mutant analysis showed that loss of CYP71A27 alters gene and protein regulation, especially during interaction with the PGP bacterium, while having limited impact on root metabolites and exudates.