High radiosensitivity in the conifer Norway spruce (Picea abies) due to lesscomprehensive mobilisation of protection and repair responses compared to the radiotolerant Arabidopsis thaliana
Authors: Bhattacharjee, P., Blagojevic, D., Lee, Y., Gillard, G. B., Gronvold, L., Hvidsten, T. R., Sandve, S. R., Lind, O. C., Salbu, B., Brede, D. A., Olsen, J. E.
The study compared early protective, repair, and stress responses to chronic gamma irradiation in the radiosensitive conifer Norway spruce (Picea abies) and the radiotolerant Arabidopsis thaliana. Norway spruce exhibited growth inhibition, mitochondrial damage, and higher DNA damage at low dose rates, while Arabidopsis maintained growth, showed minimal organelle damage, and activated DNA repair and antioxidant genes even at the lowest dose rates. Transcriptomic analysis revealed that the tolerant species mounts a robust transcriptional response at low doses, whereas the sensitive species only responds at much higher doses.
The study analyzes ancient maize genomes from a 500–600 BP Bolivian offering and compares them with 16 archaeological samples spanning 5,000 years and 226 modern Zea mays lines, revealing close genetic affinity to ancient Peruvian maize and increased diversity during Inca‑local interactions. Phylogenetic and phenotypic analyses of ovule development indicate targeted breeding for seed quality and yield, suggesting culturally driven selection was already established by the 15th century CE.
The study used comparative transcriptomics to examine how Fusarium oxysporum isolates with different lifestyles on angiosperms regulate effector genes during infection of the non‑vascular liverwort Marchantia polymorpha. Core effector genes on fast core chromosomes are actively expressed in the bryophyte host, while lineage‑specific effectors linked to angiosperm pathogenicity are silent, and disruption of a compatibility‑associated core effector alters the expression of other core effectors, highlighting conserved fungal gene networks across plant lineages.
Using a barley pangenome of 76 genotypes and a pan‑transcriptome subset of 20, the study characterizes the diversity and evolutionary dynamics of CCT motif genes, uncovering novel frameshift variants and clade‑specific domain expansions. Phylogenetic and tissue‑specific expression analyses reveal functional divergence among paralogs, and the unexpected retention of the VRN2 repressor in spring barley suggests additional regulatory mechanisms beyond vernalization.
Phylogenetic analysis reveals that non‑seed plants, exemplified by the liverwort Marchantia polymorpha, possess a streamlined repertoire of cyclin and CDK genes, with only three cyclins active in a phase‑specific manner during vegetative development. Single‑cell RNA‑seq and fluorescent reporter assays, combined with functional overexpression studies, demonstrate the distinct, non‑redundant roles of MpCYCD;1, MpCYCA, and MpCYCB;1 in G1 entry, S‑phase progression, and G2/M transition, respectively.
The study generated a high-quality genome assembly for Victoria cruziana and used comparative transcriptomics to identify anthocyanin biosynthesis genes and their transcriptional regulators that are differentially expressed between white and light pinkish flower stages. Differential expression of structural genes (VcrF3H, VcrF35H, VcrDFR, VcrANS, VcrarGST) and transcription factors (VcrMYB123, VcrMYB-SG6_a, VcrMYB-SG6_b, VcrTT8, VcrTTG1) correlates with the observed flower color change.
The study demonstrates that RNA extracted from herbarium specimens can be used to generate high‑quality transcriptomes, comparable to those from fresh or silica‑dried samples. By assembling and comparing transcriptomes across specimen types, the authors validated a plant immune receptor synthesized from a 1956 collection, proving archival RNA’s utility for functional genomics. These findings challenge the prevailing view that herbarium RNA is unsuitable for transcriptomic analyses.
The study characterizes all seven malic enzyme genes in tomato, analyzing their tissue-specific expression, temperature and ethylene responsiveness, and linking specific isoforms to metabolic processes such as starch and lipid biosynthesis during fruit development. Phylogenetic, synteny, recombinant protein biochemical assays, and promoter analyses were used to compare tomato enzymes with Arabidopsis counterparts, revealing complex evolutionary dynamics that decouple phylogeny from functional orthology.
The study sampled 94 individuals from eight Atlantic Forest populations to assess morphological and genetic variation among Inga subnuda subspecies and the related Inga vera subsp. affinis. Using plastid trnD‑trnT spacer and nuclear ITS1/2 sequences, phylogenetic analyses revealed distinct structuring of I. subnuda subsp. subnuda and a cohesive group comprising I. subnuda subsp. luschnathiana and I. vera subsp. affinis, indicating retention of ancestral polymorphism from recent diversification and prompting a taxonomic revision of subsp. luschnathiana.