Plant Cell Biology

Plant Biotechnology Group

Responsible Staff: Proff. Alma Balestrazzi, Alberta Pinnola, Anca Macovei.

The “Plant Biotechnology” laboratories and the “Plant PhotoLab” laboratory carry out research in the filed of plant molecular biology, biochemistry and genetics. By using model plants and species of agronomic interest, we are covering both basic and applied research. Multiple experimental approaches are used, including the generation of transgenic plants. Over the years, different systems have been developed and used, from in vitro cells, tissues and plant organs cultures, to plants grown in phytotron, greenhouses, or from the field.

The general objectives of these researches are to gain knowledge of some basic molecular and physiological processes and their implications for the genetic improvement of specific traits in cultivated plants related to productivity/yield, nutritional, commercial or industrial qualities of plant products, reduction of the environmental impact of modern agriculture.

Collaborators:
Technical staff for greenhouse management: Adriano Ravasio
Postdoc: Andrea Pagano
PhD students: Paola Pagano, Conrado Jr. Duenas, Adriano Griffo, Shraddha Shridhar Gaonkar

The two Plant Biotechnology Laboratories, lead by Prof. Alma Balestrazzi and Anca Macovei, conduct the following research lines:

  • Molecular profile of seed quality. Objective: identification of molecular indicators of seed vigor.

DNA repair mechanisms are activated during the early stage of seed germination (imbibition stage), when the so-called “pre-germinative metabolism” starts. A system consisting of seeds of model plants (Leguminosae, Medicago truncatula; Solanaceae, Petunia hybrida; Cereals, Orysa sativa) has been set up to validate the role of new genes involved in the DNA repair mechanisms in relation to the pre-germinative metabolism. Translational research has been subsequently launched on species of commercial interest carried out in collaboration with Italian (ISI Sementi) and foreign (Hoopmann Group) Seed Industries, Breeders (NIRP International), and with the CREA Institutes – SCV (S. Angelo Lodigiano, LO), CREA-FSO (Sanremo, IM), CREA-ORL (Montanaso Lombardo, LO). The development of new, non-invasive and easy-to-use methods to assess seed quality is part of a new collaboration with the Laboratory of Bioinformatics, Mathematical Modeling and Synthetic Biology (Department of Electrical, Computer and Biomedical Engineering-Center of Health Technologies , University of Pavia) and the Plant Germplasm Bank (Department of Earth and Environmental Sciences, University of Pavia).

A, B. Medicago truncatula, seed germination (radicle protrusion, seedlings). C. Example of Comet Assay carried out on Medicago truncatula seedlings.

  • Role of DNA repair processes in the response to genotoxic stress.

Research objectives: molecular characterization of genes involved in the response to genotoxic damage (DNA Damage Response-DDR) to investigate abiotic stress tolerance in plants. This research activity has led to the isolation and molecular characterization of new genes involved in the DNA repair processes in plants. This study, carried out in the legume model Medicago truncatula, showed for the first time the presence of the gene family TDP1 (Tyrosyl-DNA phosphodiesterase) in plants. The expression of the TDP1α and TDP1β genes is induced by oxidative/genotoxic stress, confirming the role played by these genes in the context of the DDR response activated under stress conditions. These new functions were investigated using gene silencing approaches, RNA-Seq, and genotoxicity tests (Comet Assay-Single Cell Gel Electrophoresis, DNA diffusion). A project on the use of Arabidopsis thaliana mutants defective in DDR-related genes is currently underway, in collaboration with colleagues from the University of Paris-Saclay.

Functional characterization of the MtTDP1α gene in Medicago truncatula (Donà et al. 2013, J. Exp. Bot. 64: 1941-1951). (A). Post-Transcriptional Silencing (PTS)-induced phenotype of the MtTDP1α gene. (B). Accumulation of reactive oxygen species (ROS) in leaf tissue. CTRL, control line. 1, 2a1, 2a, silenced lines.

  • MicroRNAs: roles in stress response and involvement in DDR.

A fundamental aspect of transcription regulation processes concerns the activity of microRNAs. MiRNAs contribute to the modulation of gene expression at the post-transcriptional level by inducing translation repression or gene silencing. A line of research is active that aims to investigate the role of miRNAs in the plant response to genotoxic stresses and in the context of DNA repair mechanisms. Furthermore, we are recently investigating the possible involvement of miRNAs in the regulation of DDR-associated processes through bioinformatics and experimental approaches. These new activities have applications not only for plant reserach but also for animal and biomedical studies, associated with the possible presence of plant miRNAs (taken with the diet) in other organisms. This work is carried out in collaboration with colleagues from the Laboratory of Bioinformatics, Mathematical Modeling and Synthetic Biology (Department of Electrical, Computer and Biomedical Engineering – Health Technology Center, University of Pavia) and the Institute for Sustainable Plant Protection (CNR, Research Unit of Bari).

Involvement of plant miRNAs in DNA damage response (DDR) and in trans-kingdom transfer between phylogenetically distant species.