Biology subjects

Welchen, E.

Publications and source records attributed to Welchen, E..

4 recordsLinked to original sources

bioRxiv2026

Protein-independent regulation by transgene-derived small interfering RNAs rewires endogenous regulatory networks to enhance plant growth, architecture, and drought performance

Plants produce diverse small interfering RNA (siRNA) molecules that modulate development, environmental responses, and immunity. Although transgene-derived siRNAs are traditionally viewed as mediators of gene silencing, whether they can actively regulate endogenous host pathways remains largely unexplored. Previously obtained Arabidopsis, wheat, and soybean plants expressing the sunflower gene encoding the transcription factor HaHB4 exhibited water deficit tolerance. Here, we show that expressing inverted-repeat constructs that generate HaHB4-derived siRNAs without producing the HaHB4 protein bypasses transgenic growth penalties and instead enhances vegetative vigor and reproductive performance. In Arabidopsis, these DCL-dependent siRNA-producing lines exhibited enhanced root growth, increased stem and pith areas, increased cauline branching, and higher seed yield under both optimal and water-limiting conditions. Transcriptomic analysis revealed convergent repression of biotic stress-related genes, accompanied by increased bacterial susceptibility and reduced sensitivity to salicylic acid-mediated growth inhibition, suggesting an altered balance between immunity and growth. Functional characterization of candidate endogenous HD-Zip I targets further showed that athb20 and athb53 mutants recapitulated the increased stem expansion and cauline branching of the RNAi lines, respectively, pointing to endogenous HD-Zip I genes as candidate mediators of these traits. Remarkably, these effects were observed in newly obtained transgenic soybean plants, where expression of HaHB4-derived siRNAs enhanced vegetative vigor under controlled growth conditions. Overall, these findings show that transgene-derived siRNAs act independently of protein function to rewire endogenous regulatory networks, providing a potential strategy to optimize crop architecture and yield.

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

Development of efficient RNAi methods in the corn leafhopper Dalbulus maidis, a promising application for pest control

BACKGROUNDThe corn leafhopper Dalbulus maidis is the main vector of three important stunting pathogens that affect maize production. The most common control strategy against this species is the use of insecticides that provide minimal, short-term protection. In this context, genomic-based technologies such as RNA interference (RNAi) could be a suitable approach to control this pest in a highly specific manner, avoiding the adverse effects associated with insecticide misuse. Therefore, the objective of the present work was to assess the application of RNAi on D. maidis through different dsRNA delivery methods and known the function of target gene, Bicaudal C (BicC). RESULTSWe have identified and characterized the core components of the RNAi machinery in silico and established two methods of exogenous double-stranded RNAs (dsRNA) delivery to D. maidis. BicC -an important regulator of insect oogenesis-dsRNA was successfully delivered via injection or ingestion to adult females, causing significant reductions in the transcript levels and ovipositions and observable phenotypes in the ovaries when compared to control females. The small doses of dsRNABicC administered were enough to trigger a strong RNAi response, demonstrating that D. maidis is highly sensitive to RNAi. CONCLUSIONThis is, to our knowledge, the first report describing RNAi application in D. maidis, a tool that can be used to advance towards a novel, insecticide-free control strategy against this pest.

genetics↗

bioRxiv2020

Building a pathway for diversity in plant sciences in Argentina: highlighting the work of women scientists through virtual activities

Encouraging the participation of a diverse workforce in academia increases plurality as it broadens the range of skills, ways of thinking and experiences. Institutions and professional societies have been putting efforts on building plans that help make workplaces, conferences, education and extension programs more relatable to a highly diverse population. Argentina has an overall gender-balanced workforce in the sciences (~53% women/total), with an even higher representation in disciplines related to plant sciences. However, media outlets and national conferences related to genetics, botany, plant physiology, ecology and molecular biology, fail to reflect those numbers as the proportion of women invited for interviews, plenary lectures, and symposia falls below ~30%. As a way to increase the visibility of the wealth of plant science topics and experimental approaches in which Argentinian women work, and to facilitate connections among them across the country and abroad, we created the Argentinian Women in Plant Science network (https://argplantwomen.weebly.com/). This group has grown to over 200 members, representing a wide range of career stages and research topics. Since April, and taking advantage of the confinement situation, our weekly webinar series highlighting women plant scientists has reached an average audience of 60-70 participants, with a record of 100. Recently, we have begun a series of open professional development webinars to reach a wider public. Our first webinar, focused on Scientific poster design, had ~250 participants, most of them undergrad and graduate students from all over the country covering a diverse range of disciplines, including the social sciences. Even though we have immersed ourselves in the plant science community with our weekly seminars, we have expanded our goals with activities aimed to reach out to a much wider audience with webinars and teacher training workshops, hopefully making plant science more attainable to all.

scientific communication and education↗