MdBRC1 and MdFT2 Interaction Fine-Tunes Bud Break Regulation in Apple
Authors: Gioppato, H. A., Estevan, J., Al Bolbol, M., Soriano, A., Garighan, J., Jeong, K., Georget, C., Soto, D. G., El Khoury, S., Falavigna, V. d. S., George, S., Perales, M., Andres, F.
The study identifies the transcription factor MdBRC1 as a key inhibitor of bud growth during the ecodormancy phase in apple (Malus domestica), directly regulating dormancy‑associated genes and interacting with the flowering promoter MdFT2 to modulate bud break. Comparative transcriptomic analysis and gain‑of‑function experiments in poplar demonstrate that MdFT2 physically binds MdBRC1, attenuating its repressive activity and acting as a molecular switch for the transition to active growth.
The study applied the STOmics spatial transcriptomics platform to map gene expression at subcellular resolution in developing wheat (Triticum aestivum) seeds during grain filling, analyzing over four million transcripts. Eight functional cellular groups were identified, including four distinct endosperm clusters with radial expression patterns and novel marker genes, and subgenome‑biased expression was observed among specific paralogs. These results highlight spatial transcriptomics as a powerful tool for uncovering tissue‑specific and polyploid‑specific gene regulation in seeds.
Spatial and single-cell transcriptomics capture two distinct cell states in plant immunity
Authors: Hu, Y., Schaefer, R., Rendleman, M., Slattery, A., Cramer, A., Nahiyan, A., Breitweiser, L., Shah, M., Kaehler, E., Yao, C., Bowling, A., Crow, J., May, G., Tabor, G., Thatcher, S., Uppalapati, S. R., Muppirala, U., Deschamps, S.
The study combined spatial transcriptomics and single-nuclei RNA sequencing to map soybean (Glycine max) responses to Asian soybean rust caused by Phakopsora pachyrhizi, revealing two distinct host cell states: pathogen‑occupied regions and adjacent non‑infected regions that show heightened defense gene expression. Gene co‑expression network analysis identified a key immune‑related module active in the stressed cells, highlighting a cell‑non‑autonomous defense mechanism.
The study introduced full-length SOC1 genes from maize and soybean, and a partial SOC1 gene from blueberry, into tomato plants under constitutive promoters. While VcSOC1K and ZmSOC1 accelerated flowering, all three transgenes increased fruit number per plant mainly by promoting branching, and transcriptomic profiling revealed alterations in flowering, growth, and stress‑response pathways.
Imputation integrates single-cell and spatial gene expression data to resolve transcriptional networks in barley shoot meristem development
Authors: Demesa-Arevalo, E., Dorpholz, H., Vardanega, I., Maika, J. E., Pineda-Valentino, I., Eggels, S., Lautwein, T., Kohrer, K., Schnurbusch, T., von Korff, M., Usadel, B., Simon, R.
The study uses an imputation strategy that integrates deep single-cell RNA sequencing with spatial gene expression data to map transcriptional dynamics across barley inflorescence development at cellular resolution. By leveraging the BARVISTA web interface, the authors identify key transcriptional events in meristem founder cells, characterize complex branching mutants, and reconstruct spatio‑temporal trajectories of flower organogenesis, offering insights for targeted trait manipulation.
Revisiting the Central Dogma: the distinct roles of genome, methylation, transcription, and translation on protein expression in Arabidopsis thaliana
Authors: Zhong, Z., Bailey, M., Kim, Y.-I., Pesaran-Afsharyan, N., Parker, B., Arathoon, L., Li, X., Rundle, C. A., Behrens, A., Nedialkova, D. D., Slavov, G., Hassani-Pak, K., Lilley, K. S., Theodoulou, F. L., Mott, R.
The study combined long‑read whole‑genome assembly, multi‑omics profiling (DNA methylation, mRNA, ribosome‑associated transcripts, tRNA abundance, and protein levels) in two Arabidopsis thaliana accessions to evaluate how genomic information propagates through the Central Dogma. Codon usage in gene sequences emerged as the strongest predictor of both mRNA and protein abundance, while methylation, tRNA levels, and ribosome‑associated transcripts contributed little additional information under stable conditions.
Impaired methyl recycling induces substantial shifts in sulfur utilization in Arabidopsis
Authors: Tremblay, B. J.-M., Adeel, S. A., Saechao, M., Dong, Y., Andrianasolo, E., Steele, J. M., Traa, A., Yogadasan, N., Waduwara-Jayabahu, I., Katzenback, B. A., Hell, R., Wirtz, M., Moffatt, B. A.
Reduced activity of methylthioadenosine (MTA) nucleosidase causes MTA over‑accumulation in reproductive tissues, leading to lowered cysteine, methionine, and S‑adenosylmethionine levels and altered sulfur and energy metabolism. These metabolic disturbances trigger misregulation of cell‑cycle progression, widespread down‑regulation of developmental genes, and genome‑wide changes in DNA methylation patterns, highlighting the extensive role of MTA recycling in plant growth and methyl‑index maintenance.
Arabidopsis REM transcription factors and GDE1 shape the DNA methylation landscape through the recruitment of RNA Polymerase IV transcription complexes.
Authors: Wu, Z., Xue, Y., Wang, S., Shih, Y.-H., Zhong, Z., Feng, S., Draper, J., Lu, A., Sha, J., Li, L., Wohlschlegel, J., Wu, K., Jacobsen, S. E.
The study identifies four Arabidopsis REM transcription factors (VDD, VAL, REM12, REM13) that bind specific DNA sequences and, together with GDE1, recruit RNA polymerase IV to produce 24‑nt siRNAs that direct DNA methylation at designated loci. Loss of GDE1 causes Pol IV complexes to relocalize to sites bound by REM8, indicating that REM proteins provide sequence‑specific cues for epigenetic patterning.
The study reveals that a set of REPRODUCTIVE MERISTEM (REM) transcription factors, termed RIMs, are essential for directing RNA‑directed DNA methylation (RdDM) to CLSY3 targets in a sex‑specific manner in Arabidopsis reproductive tissues. Disruption of RIM DNA‑binding domains or their target motifs abolishes RdDM at these loci, demonstrating that genetic cues can guide de novo methylation patterns.
The study generated two allotriploid Brassica hybrids (ArAnCn) to investigate asymmetric subgenome dominance, finding that the Cn subgenome dominates despite the An subgenome showing highest expression levels. Increased density of accessible chromatin regions (ACRs) in the Cn subgenome correlates with dominant gene expression, while changes in CHH methylation and specific RNA‑directed DNA methylation pathway mutants affect subgenome bias.