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 examined how plant‑derived benzoxazinoid metabolites influence interactions among root‑associated bacterial strains and between these bacteria and their plant host. Using both simple pairwise assays and more complex multi‑organism setups, the authors found that these chemicals modulate bacterial‑bacterial and bacterial‑plant interactions, altering plant defense, immunity, and sugar transport especially when bacterial inocula are present. The work highlights the role of the soil chemical legacy in shaping holobiont dynamics and demonstrates the utility of combining reductionist and holistic experimental approaches.
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.
The study compares iron deficiency and drought tolerance between two soybean genotypes, Clark (tolerant) and Arisoy (sensitive), using multi‑omics analyses. Clark maintains iron homeostasis, higher antioxidant protein expression, and recruits beneficial root microbes (Variovorax, Paecilomyces) that support nutrient uptake and nodule function, while Arisoy shows impaired physiological and microbial responses. The findings identify host‑microbe interactions and specific molecular pathways as potential targets for breeding and microbiome‑based biofertilizers.
The study shows that drought triggers ABA accumulation and JA reduction in sorghum roots, accompanied by transcriptional activation of genes linked to mineral homeostasis, hormone signaling, and osmotic regulation, while Fe supplementation enhances ferritin expression and mitigates oxidative stress. Drought also diminishes root bacterial diversity but enriches beneficial taxa such as Burkholderia, whereas fungal diversity remains stable, and functional profiling reveals shifts toward phototrophy, methylotrophy, and nitrate reduction. These findings highlight ferritin’s protective role and suggest specific bacterial inoculants for improving sorghum drought resilience.