KATANIN promotes cell elongation and division to generate proper cell numbers in maize organs
Authors: Martinez, S. E., Lau, K. H., Allsman, L. A., Irahola, C., Habib, C., Diaz, I. Y., Ceballos, I., Panteris, E., Bommert, P., Wright, A. J., Weil, C., Rasmussen, C.
The study identifies two maize genes, Discordia3a and Discordia3b, that encode the microtubule‑severing protein KATANIN. Loss‑of‑function allele combinations reduce microtubule severing, impair cell elongation, delay mitotic entry, and disrupt preprophase band and nuclear positioning, leading to dwarfed, misshapen plants.
Six new Viola species and two reinstated species from China were identified using field surveys, detailed morphological comparison, and phylogenetic analysis of ITS and GPI gene sequences, placing them in section Plagiostigma subsect. Diffusae. The GPI data offered higher resolution, indicating complex relationships possibly due to ancient hybridization or incomplete lineage sorting, thereby clarifying species boundaries and evolutionary patterns in Chinese Viola.
Sorghum embryos undergoing B chromosome elimination express B-variants of mitotic-related genes
Authors: Bojdova, T., Hlouskova, L., Holusova, K., Svacina, R., Hribova, E., Ilikova, I., Thiel, J., Kim, G., Pleskot, R., Houben, A., Bartos, J., Karafiatova, M.
The study characterizes tissue-specific elimination of B chromosomes in Sorghum purpureosericeum during embryo development, identifying 28 candidate genes linked to this process. Integrated in situ visualization, genome sequencing, and transcriptomic analyses reveal that the B chromosome originates from multiple A chromosomes, harbors unique repeats, and expresses divergent kinetochore components that likely mediate its selective removal.
The study evaluated whether integrating genomic, transcriptomic, and drone-derived phenomic data improves prediction of 129 maize traits across nine environments, using both linear (rrBLUP) and nonlinear (SVR) models. Multi-omics models consistently outperformed single-omics models, with transcriptomic data especially enhancing cross‑environment predictions and capturing genotype‑by‑environment interactions. The results highlight the added value of combining transcriptomics and phenomics with genotypes for more accurate and generalizable trait prediction in maize.
Phytoplasma infection in sesame (Sesamum indicum) triggers tissue-specific alterations in gene expression and metabolite composition, with floral organs adopting leaf-like traits and distinct changes in porphyrin, brassinosteroid, and phenylpropanoid pathways. Integrated transcriptomic and metabolomic analyses, supported by biochemical, histological, and qRT-PCR assays, reveal differential stress and secondary metabolite responses between infected leaves and flowers.
The study identified lineage-specific long non‑coding RNAs (lncRNAs) from the aphid‑specific Ya gene family in Rhopalosiphum maidis and R. padi, demonstrating that these Ya lncRNAs are secreted into maize, remain stable, and move systemically. RNA interference of Ya genes reduced aphid fecundity, while ectopic expression of Ya lncRNAs in maize enhanced aphid colonization, indicating that Ya lncRNAs act as cross‑kingdom effectors that influence aphid virulence.
The study provides a comprehensive genome-wide catalog and single‑cell expression atlas of the carbonic anhydrase (CA) gene family in maize, identifying 18 CA genes across α, β, and γ subfamilies and detailing their structural and regulatory features. Phylogenetic, synteny, promoter motif, bulk tissue RNA‑seq, and single‑cell RNA‑seq analyses reveal distinct tissue and cell‑type specific expression patterns, highlighting β‑CAs as key players in C4 photosynthesis and γ‑CAs in ion/pH buffering, and propose cell‑type‑specific CA genes as targets for improving stress resilience.
The study used a computer‑vision phenotyping pipeline (EarVision.v2) based on Faster R-CNN to map Ds‑GFP mutant kernels on maize ears and a statistical framework (EarScape) to assess spatial patterns of allele transmission from the apex to the base. They found that alleles causing pollen‑specific transmission defects often show significant spatial biases, whereas Mendelian alleles do not, indicating that reduced pollen fitness can shape the spatial distribution of progeny genotypes in Zea mays.
The study presents a plant‑focused phylogenetic analysis of class B flavin‑dependent monooxygenases, identifying eight distinct families and revealing lineage‑specific diversification, especially in the NADPH‑binding domain. Using known FMOs as baits, they assembled flavin‑related proteins from key Viridiplantae lineages, performed domain architecture and motif analyses, and reclassified several families, providing a framework for future functional studies.
Evolutionary origin and functional mechanism of Lhcx in the diatom photoprotection
Authors: Kumazawa, M., Akimoto, S., Takabayashi, A., Imaizumi, K., Tsuji, S., Hasegawa, H., Sakurai, A., Imamura, S., Ishikawa, N., Inoue-Kashino, N., Kashino, Y., Ifuku, K.
Molecular phylogenetic analysis indicated that diatom Lhcx proteins share a common ancestor with green algal Lhcsrs, suggesting acquisition via horizontal gene transfer. Knockout of the Lhcx1 gene in the diatom Chaetoceros gracilis almost eliminated non‑photochemical quenching and revealed that Lhcx1 mediates quenching in detached antenna complexes, while also influencing PSII quantum yield and carbon fixation under high‑light conditions. These findings elucidate the evolutionary origin and mechanistic role of Lhcx‑mediated photoprotection in diatoms.