A Russian researcher, together with a colleague from Singapore, summarized data on tissue regeneration in plants at the individual cell level. The scientists noted that thanks to modern technologies, observations demonstrate that recovery can occur not only due to stem cells, but also by asymmetric (regenerative) division of other types of cells located around the damaged area. Understanding processes at the cellular level is important for developing personalized strategies for damage recovery in agricultural crops.
Bioinformaticians Victoria Mironova (Novosibirsk State University, Institute of Cytology and Genetics SB RAS) and Jian Xu (National University of Singapore and Radboud University Nijmegen, the Netherlands) examined four scenarios for what happens when a cell is damaged or receives a signal that its closest neighbors have been “traumatized”. The cell can die, share, dedifferentiate, or transdifferentiate. The last two modifications are a form of regression in its development. In the first case, the cell “gets younger” returning to the stage when it can divide (not every cell has this ability). In the second case, the cell changes its specialization profile, for example, the vascular becomes epidermal. Such transformations can even reproduce a dead cell type. It turned out that all four response methods, including cell death, are necessary for successful tissue regeneration.
The key process leading to tissue repair is regenerative (asymmetric) cell division that receives a signal about the damage to their “colleagues”. After this division, daughter cells are different with some of them parent copies while others recreate cells lost as a result of damage.
Victoria Mironova, Lead Researcher in the Systemic Biology Sector of Plant Morphogenesis at the Institute of Cytology and Genetics, Senior Researcher at the NSU Computational Transcriptomics and Evolutionary Bioinformatics Laboratory, Candidate of Biological Sciences and lead author for the journal article presenting this work, talked about their research.
Single cell transcriptomics (SCT) is a new, actively developing approach that will allow us to determine the functions and type of an individual cell at any given time. This method reveals which genes in a biological subject are active in all cells. For example, a plant root or mouse embryo, the biological markers of a particular tissue are found using bioinformatic post-processing which makes it possible to typify a cell. The first research described the application of SCT technology to study regeneration issues in both animals and plants. For example, it turned out that the restoration of a completely remote root tip with a stem cell niche in it can occur in the absence of the latter due to non-stem cells in the surrounding tissues.
SCT research first appeared in publications on this topic only two years ago. This year, the first articles were published on single cell transcriptomics being used to study plant tissues at the root. This is a type of model organ with a simple structure alternating different tissues that makes it relatively easy to identify cell type markers.
This new method makes it possible to work with a previously inaccessible degree of detail. For example, we were able to establish that callus cells (tissue developing on plant wound surfaces) are heterogeneous and not all are pluripotent stem cells. This contradicted the previous assumption.
Bioinformatic post-processing of SCT data along with the use of mathematical modeling methods is of great importance and a focus of work at the NSU Computational Transcriptomics and Evolutionary Bioinformatics Laboratory and the Systemic Biology Sector of Plant Morphogenesis at the Institute of Cytology and Genetics. This research helps to suggest how regeneration will develop in time and space because SCT experiments determine the function and type of cells.
