Search bioRxiv⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/430439

Switching toxic protein function in life cells

Dissmeyer, N.·Faden, F.·Mielke, S.
View original source ↗Export metadata ↓

Abstract

Toxic proteins are prime targets for molecular farming and efficient tools for targeted cell ablation in genetics, developmental biology, and biotechnology. Achieving conditional activity of cytotoxins and their maintenance in form of stably transformed transgenes is challenging. We demonstrate here a switchable version of the highly cytotoxic bacterial ribonuclease barnase by using efficient temperature-dependent control of protein accumulation in living multicellular organisms. By tuning the levels of the protein, we were able to control the fate of a plant organ in vivo. The on-demand-formation of specialized epidermal cells (trichomes) through manipulating stabilization versus destabilization of barnase is a proof-of-concept for a robust and powerful tool for conditional switchable cell arrest. We present this tool both as a potential novel strategy for the manufacture and accumulation of cytotoxic proteins and toxic high-value products in plants or for conditional genetic cell ablation.

Source connections

Explore related subjects

plant biologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Dissmeyer, N., Faden, F., Mielke, S.. 2018-09-29. Switching toxic protein function in life cells. https://doi.org/10.1101/430439

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Compost-associated microbiota modulates root transcriptional responses and enhances tomato drought resilience

Compost is a promising sustainable alternative to mineral fertilization because it supplies nutrients and organic matter while hosting diverse microbial communities. However, even if its application to plants has been proven to alleviate different biotic and abiotic stresses, it remains unclear whether its benefits arise from its physico-chemical properties, its associated microbiota, or both. In this study, we compared the impact of compost, sterile compost and an NPK treatment providing equivalent macronutrient inputs on tomato plants cv. Micro-Tom. After assessing physiological parameters of the leaves and molecular responses of the roots under optimal conditions, we performed a drought stress experiment under the three fertilization treatments, complementing the analysis with the investigation of substrate water-retention properties. Although all fertilized treatments improved plant performance relative to nutrient-poor soil, RNA sequencing revealed distinct root transcriptional profiles among compost, sterile compost and NPK, with the compost treatment upregulating several pathways related to plant growth and health, such as hormone signaling, nutrient metabolism, and stress responses. When subjected to severe water stress, compost-treated plants retained the highest photosynthetic efficiency and compost showed the highest available water content compared to the other treatments. These findings suggest that compost may enhance tomato drought resilience through combined effects of substrate water availability and compost-associated microbiota.

plant biology↗
bioRxiv2026

Organic Fertilizer Substitution for Chemical Fertilizer Improves Yield, Medicinal Active Compounds and Amino-Acid Profiles of Dendrobium officinale with Multi-Index Comprehensive Evaluation

Dendrobium officinale (D. officinale) is an important medicinal horticultural crop. Its wild resources are threatened by over-exploitation. Fertilization regimes that balance yield and medicinal quality are urgently required for its artificial cultivation. This study aimed to investigate the effects of reduced chemical fertilizer combined with organic fertilizer on the yield and quality of D. officinale, and screen the optimal combined fertilization pattern, so as to provide a theoretical basis for standardized fertilization in D. officinale cultivation. A bed-cultivation experiment was carried out in greenhouse. Seven treatments were set up, including no fertilizer application (CK), sole chemical fertilizer (CF), 20% organic fertilizer substitution for chemical fertilizer (T20), 40% organic fertilizer substitution for chemical fertilizer (T40), 60% organic fertilizer substitution for chemical fertilizer (T60), 80% organic fertilizer substitution for chemical fertilizer (T80), and single organic fertilizer application (OM). Plant growth traits, yield, active ingredients, protein and amino acid components of D. officinale were determined. The membership function method was adopted for comprehensive evaluation of all treatments. Fertilization significantly improved the growth traits, yield and quality of D. officinale. Compared with CK, stem length, stem diameter and yield under fertilized treatments increased significantly by 15.5%-60.3%, 34.2%-64.7% and 65%-143.2%, respectively; dendrobine, polyphenols and alcohol-soluble extract contents increased significantly by 21.2%-83.7%, 14.0%-49.1% and 10.8%-26.9%, respectively. The highest plant growth and yield were observed under sole chemical fertilizer treatment. With the increase of organic fertilizer substitution ratio, plant growth and yield decreased gradually, while medicinal active ingredients including dendrobine, polysaccharides and flavonoids showed a trend of rising first and then falling. A total of 17 amino acids were detected in all treatments. T40 and T60 treatments significantly increased total amino acids, essential amino acids, as well as contents of medicinal, umami and bitter-tasting amino acids, whereas excessive proportion of organic fertilizer led to the decline of amino acid contents. Most growth, quality and amino acid indicators showed significant or extremely significant positive correlations with each other. The comprehensive evaluation order by membership function method was T40 > T60 > CF > T20 > T80 > OM > CK, and T40 obtained the highest comprehensive evaluation value. Sole chemical fertilizer contributes to yield increase of D. officinale, while combined application with organic fertilizer improves its medicinal quality. The 40?% organic substitution scheme provides a feasible fertilization strategy for high-quality greenhouse production of this medicinal horticultural plant.

plant biology↗
bioRxiv2026

Large-scale forward genetics reveals genetically separable components of plant cell proliferative capacity

Plant cell cultures underpin regeneration, transformation and emerging applications in biotechnology and plant cell agriculture, yet the genetic determinants of proliferative performance remain poorly characterized. Here, we combined large-scale forward genetics with automated image-based phenotyping to quantify 27,648 calli representing 2,880 Arabidopsis thaliana T-DNA insertion lines. Of these, 2,456 lines produced calli smaller than the WT population mean, whereas only 190 produced larger calli, revealing a strongly asymmetric phenotypic distribution. Enhanced callus growth was not consistently associated with increased vegetative growth, indicating that these traits can be genetically uncoupled. Validation of selected high-growth mutants in suspension culture identified lines with enhanced biomass accumulation, while serial propagation revealed independent variation in sustained proliferative capacity. Thus, callus growth, whole-plant growth, short-term suspension biomass accumulation and sustained proliferation represent distinct, not necessarily coupled components of proliferative performance. These findings establish a scalable framework for identifying genetic determinants relevant to the development of improved plant cell production lines.

plant biology↗