Biology subjects

Cabello, J. V.

Publications and source records attributed to Cabello, J. V..

4 recordsLinked to original sources

bioRxiv2026

Mechanical stress modulates source-to-sink partitioning and drought response in Arabidopsis

Mechanical stimuli provoked by wind, soil compaction, rainfall, and biotic interactions strongly influence plant phenotype, growth, and development. Previous studies indicated that weight-treated Arabidopsis thaliana plants increase stem diameter, vascular bundle number, and seed yield, involving auxin, brassinosteroid, and strigolactone-related genes. In this work, we investigated how the mechanically induced increase in phloem area improves source-to-sink partitioning, while the increase in xylem area negatively affects long-term drought tolerance. Transcriptomic profiling confirmed a large-scale reprogramming of drought-responsive genes in treated plants. Moreover, quantification of sucrose and starch content highlighted an enhanced synthesis and carbohydrate transport, which ultimately and positively impacted lipid and protein contents in seeds. Using loss-of-function mutants, we demonstrate that the phloem loader SUC2 and exporters SWEET11, 12, and 16 are essential for the yield gains triggered by mechanical stress. Furthermore, mechanical treatment alters sugar metabolism. Overall, our findings indicate that weight treatment elicits a complex physiological response, in which sucrose transporters and starch metabolism play a crucial role in mediating its positive effects on seed quality and yield. Significance statementMechanical cues are ubiquitous in natural environments, but their impact on plant carbon allocation and yield remains poorly understood. This study reveals that mechanical stress reshapes vascular architecture and carbohydrate transport, enhancing source-to-sink partitioning and seed quality in Arabidopsis. By identifying sucrose transporters and sugar metabolism as key mediators of mechanically induced yield gains, our findings provide mechanistic insight into how physical forces integrate with metabolic regulation influence plant productivity.

plant biology↗

bioRxiv2024

Mechanical stress induces anatomical changes, tomato early flowering, and increased yield involving ethylene and auxins

Plants have evolved mechanisms to perceive and face mechanical stress (MS) caused by physical forces, including compacted soils, winds, rain, pathogens, and interactions with animals and plants. Previous research indicated that applying mechanical treatment (MT) to Arabidopsis increases both xylem area and seed yield. To explore sustainable tomato production, we applied MT - combining stem bending, weighting, and particular touching - to 10-day-old seedlings, using a specific weight on the upper stem for 48 h. Two days after the treatment, we observed stem enlargement and increased the number of xylem vessels and area in MT plants. Additionally, we noticed earlier flowering, leading to increased tomato production. The transcriptome of MT-treated plants revealed significant changes in the expression of several essential genes involved in central metabolism, growth responses, and crucial phytohormone signalling. By studying different tomato mutants in the ethylene and auxin signalling pathways, we demonstrated that both hormones play essential roles in the plant responses to combined MT. Our findings suggest that combined MT generates a beneficial MS in tomato plants that induces plant morphoanatomical changes that promote early flowering and increased yield, providing a promising strategy for sustainable agriculture. HighlightA combined mechanical treatment applied to tomato seedlings enhances stem width, increases the number of vascular bundles, promotes early flowering, and improves fruit yield, involving auxin and ethylene pathways.

plant biology↗

bioRxiv2022

Source to sink partitioning is altered by the expression of the transcription factor AtHB5

Carbohydrates are transported from source to sink tissues. The efficiency of such transport determines plant growth and development. The process is finely regulated, and transcription factors are crucial in such modulation. AtHB5 is a homeodomain-leucine zipper I transcription factor, repressed during stem secondary growth. However, its function in this developmental event was unknown. Here, we investigated the expression pattern and role of AtHB5. AtHB5 localized in conductive tissues: roots, hypocotyls, stems, pedicels, and central leaf veins. Mutant plants exhibited wider and more lignified stems than controls, whereas overexpressors showed the opposite phenotype. Cross-sections of athb5 mutant stems showed enlarged vascular bundle, xylem, phloem, and petiole areas, whereas AtHB5 overexpressors exhibited callose deposits. Several genes involved in starch biosynthesis and degradation had altered transcript levels in athb5 mutants and AtHB5 overexpressors. Rosette and stem biomasses were enhanced in athb5 mutants, positively impacting seed yield and lipid content. Moreover, these effects were more evident in debranched plants. Finally, the transport to roots significantly slowed down in AtHB5 overexpressors. Altogether, the results indicated that AtHB5 is a negative modulator of sucrose transport from source to sink tissues, and its overexpression diminished plant biomass and seed yield. HighlightThe homeodomain-leucine zipper transcription factor AtHB5 is expressed in different tissues along the life cycle, repressing carbohydrate transport from source to sink and promoting callose and lignin deposition. AtHB5 mutants exhibit physiological differences with the wild-type, impacting seed yield and lipid content.

plant biology↗

bioRxiv2019

Successful field performance in dry-warm environments of soybean expressing the sunflower transcription factor HaHB4

Soybean yield is limited primarily by abiotic constraints. No transgenic soybean with improved abiotic-stress tolerance is available in the market. We transformed soybean plants with genetic constructs able to express the sunflower transcription factor HaHB4, which confers drought tolerance to Arabidopsis and wheat plants. One line (b10H) carrying the sunflower promoter was chosen among three independent lines because it exhibited the best performance in seed yield (SY). Such line was evaluated in the greenhouse and in twenty-seven field trials developed in different environments of Argentina. In greenhouse experiments, transgenic plants showed increased SY under stress conditions together with wider epycotyl diameter, enlarged xylem area and enhanced water use efficiency than controls. They also exhibited enhanced SY in warm-dry field conditions. This response was accompanied by the increased in seed number that was not compensated by the decreased in individual seed weight. The transcriptome analysis of plants from a field trial with maximum SY difference between genotypes indicated an induction of genes encoding redox and heat shock proteins in b10H. Collectively, our results indicate that soybeans transformed with HaHB4 are expected to have reduced SY penalization when cropped in warm-dry conditions, which constitute the best target environments for this technology. HighlightSoybean transformed with the sunflower gene encoding the transcription factor HaHB4 was evaluated in greenhouse and field trials. Transgenic plants significantly outyielded controls in drought-warm environments due to, at least in part, increased seed number, xylem area, and water use efficiency as well as to the induction of genes encoding redox and heat shock proteins.

plant biology↗