Research area
Cell and developmental biology
Plant biology

MOLECULAR BASIS OF PLANT DEVELOPMENT

Research

Our laboratory studies the molecular bases of cell size regulation in plant cells. Root hairs are single plant cells that play a key role in the acquisition of nutrients and water, in soil anchorage and soil formation, and in the interaction with soil microorganisms. Their expansion is polar and directional, which makes them an excellent model system to investigate how a plant cell controls its final size. We work mainly with Arabidopsis thaliana and tomato in house, and with Medicago sativa, Vitis vinifera and Citrus as part of collaborative and translational efforts. A better understanding of how root hair development drives nutrient and water uptake, and of root anchorage in soils where nutrients are one of the most important limiting factors, is crucial to improve plant growth and seed and fruit productivity. Root hair growth integrates external signals (nutrients, water, temperature, soil microbiota) with endogenous factors such as hormones (e.g. auxin, ethylene). In recent years we have also started several international collaborations with groups specialised in soil microorganisms associated with plant roots. Our long-term goal is to generate deep basic knowledge on how roots grow that can be applied in the future to improve nutrient and water uptake in food-producing plants in Argentina and the region.

Key research lines (2026–2029)

Research Line 1. Cell surface perception and downstream signalling. Functions of RALF (Rapid Alkalinization Factor) peptides that control the signalling pathway involving FERONIA (FER) receptor-like kinases during root hair growth. How are RALF–FER downstream components of the signalling cascades linked to extracellular signals such as nutrients, water and temperature? Downstream of the RALF–FER pathway, we are studying how the nutrient sensor TOR kinase is coupled to root hair cell elongation under contrasting environmental conditions

Research Line 2. Root hair growth is directed by new transcriptional regulatory networks under complex abiotic stress. How are temperature conditions and nutrient deficiency decoded as extracellular stimuli in a defined transcriptional network in these individual plant cells? We are extending this question to low and high temperature, salinity and low phosphate and nitrate availability, with a particular focus on the early transcriptional responses (first hours) to these signals. We identify the transcriptional networks controlled by transcription factors active in root hair cells using single-nuclei RNA-seq and bulk RNA-seq combined with DAP-seq and ChIP-seq approaches.

Research Line 3. Molecular dialogue between soil microorganisms and roots. We are dissecting the molecular mechanisms underlying the interaction of Arabidopsis and tomato roots with plant-growth-promoting bacteria (Methylobacterium, Flavobacterium and Pseudomonas) and fungi (Humicolopsis). Using mutants, overexpressors and reporter lines together with dual RNA-seq and secretome proteomics, we aim to identify new components of these interactions. We also plan to screen microorganisms from extreme environments, such as Antarctica and the Puna desert, that have evolved at the limits of microbial life.

Research Line 4. Development of super-adaptable plants with modified root architecture. We have generated tomato and alfalfa lines with longer and denser root hairs to test whether they support more efficient nutrient uptake and improved drought and salt stress tolerance. We are also transforming Vitis vinifera rootstocks and Citrus within the Redes Federales network grant.

Skills & tools

To understand the molecular mechanisms that regulate how plant cells expand, we use a wide range of experimental approaches:
1. Genetics and molecular biology techniques. Isolation of single and multiple mutants (T-DNA and CRISPR-Cas lines, RNAi and amiRNA), inducible and overexpressing lines. Genetic complementation driven by endogenous promoters. Phenotypic characterisation of mutants and overexpressors. Analysis of co-expressed genes and gene regulatory networks. Global characterisation of the plant genome using RNA-seq and ChIP-seq, single-nuclei RNA-seq and DAP-seq.
2. Cell biology methods. Confocal microscopy of fluorescent-protein-tagged lines at tissue and single-cell level. Protein reporters. Fluorescent biosensors (Yellow Cameleon YC3.6, Hyper7 and roGFP) for real-time measurement of ROS and Ca2+. Protein–protein interaction techniques (e.g. FRET and BiFC). Co-localisation methods.
3. Biochemical methods. Pharmacological inhibition of target enzymes. Isolation of small molecules with growth-promoting activity. Glycobiology of plant cells and glycosylation status of cell wall glycoproteins. Enzymatic activity assays, secretome proteomics.
4. Plant–microbe interaction methods. Co-cultivation and bioassay systems for bacterial and fungal strains with roots, dual RNA-seq of both partners, and analysis of secreted molecules and volatile compounds.
5. Plant transformation and translational biotechnology. Stable transformation and CRISPR-Cas editing of tomato, alfalfa, Vitis vinifera rootstocks and Citrus to modify root architecture and root hair traits.

Collaboration interests

  • RNA-seq, DAP-seq and ChIP-seq sequencing with a particular focus on root biology, including single-nuclei RNA-seq of root epidermal cell types.
  • ROS and Ca2+ biosensors and confocal microscopy.
  • Development of more tolerant crops: tomato, Medicago, Vitis vinifera and Citrus.
  • Plant–microbe interactions: bacterial and fungal strains that promote root growth and stress resilience, including screening of microorganisms from extreme environments (Antarctica, Puna desert).
  • Root hair biology under multilayered abiotic stress: low and high temperature, salinity, and phosphate and nitrate deficiency.

Selected publications

  • URZÚA LEHUEDÉ, Tomás, et al. Two antagonistic gene regulatory networks drive Arabidopsis root hair growth at low temperature linked to a low‐nutrient environment. New Phytologist, 2025, vol. 245, no 6, p. 2645-2664.
  • GABARAIN, Victoria Berdion, et al. Enhanced auxin signaling promotes root-hair growth at moderately low temperature in Arabidopsis thaliana. Plant Communications, 2025, vol. 6, no 6.
  • MICHARD, Erwan; ESTEVEZ, José M. MLOs downstream of FERONIA help to maintain root hair apical growth by tuning Ca2+ and ROS secondary messengers’ oscillations. 2025.
  • RODRÍGUEZ-GARCÍA, Diana R., et al. Transcription factor NAC1 activates expression of peptidase-encoding AtCEPs in roots to limit root hair growth. Plant physiology, 2024, vol. 194, no 1, p. 81-93.
  • MARTINEZ PACHECO, Javier, et al. Cell surface receptor kinase FERONIA linked to nutrient sensor TORC signaling controls root hair growth at low temperature linked to low nitrate in Arabidopsis thaliana. bioRxiv, 2022, p. 2022.01. 10.475584.
  • PACHECO, Javier Martínez, et al. Apoplastic class III peroxidases PRX62 and PRX69 promote Arabidopsis root hair growth at low temperature. Nature Communications, 2022, vol. 13, no 1, p. 1310.
  • LI, Jianwei, et al. Posttranslational regulation of TOR kinase activity controls resource allocation between plant growth and immunity in Arabidopsis. Molecular Plant, 2026, vol. 19, no 3, p. 629-650.

Principal investigator

Jose Manuel Estevez, PhD

[email protected]

  • root hair growth
  • nutrient sensing
  • calcium signaling
  • transcriptional networks
  • plant development
  • cell wall and extensins
  • plant–microbe interactions
  • abiotic stress
  • TOR signalling
  • crop root architecture