Cell Biology of Plant Development

Summary

Crop yield is a trait that depends on multiple environmental factors, including the availability of water and nutrients, temperature, quality and quantity of light, etc. In addition, parameters that define the architecture of plants and the size of their organs determine, along with these environmental factors, crop yields.

The development of plant organs is based on a common general scheme. After the different cell types are established, a stage of cell proliferation occurs. The cells then begin cell expansion and differentiation to reach their final size, shape, and function. Thus, the number, size, and final shape of plant organs depends on the location, duration, magnitude, and direction of these processes.

Our group aims to analyze the development and growth of plant organs at the cellular level to identify mechanisms that regulate cell proliferation, expansion, and cell differentiation. To this end, we make extensive use of microscopy, genomics, genetics, and molecular biology techniques to determine the cellular parameters that define the growth of plant organs and to analyze expression patterns and subcellular localization of the proteins that regulate these processes. We also analyze the interaction of these mechanisms with the environment and the possibility of transferring this knowledge to species of agronomic interest.

Research Lines

Mechanisms that modulate the growth of plant organs by controlling cell proliferation

There are important similarities in the mechanism of growth of all plant organs. Once the different cell types are established by the stem cells, cells go through a stage of active cell proliferation in which new cells are produced by mitosis. These cells then go through a phase of expansion and differentiation until they reach the mature functional state. The final size of each organ depends on the number of cells produced by the meristems and the size the cells acquire after the expansion period.

The new cells are produced by mitosis in the meristematic zones of developing organs. Therefore, controlling progression through the Mitotic Cell Cycle (MCC) phases is critical in determining the magnitude of plant organ growth. The genetic mechanisms that control the parameters that define the magnitude of cell production regulate the size and persistence over time of the proliferation zone, and others, the rate of the cell cycle at which cells in this zone divide. In this line of research, we aim to identify and characterize regulatory modules that control the cell cycle in plants at the transcriptional and post-transcriptional level and promote their development and growth, with the ultimate goal of generating tools that allow increasing crop yields to improve food and biofuel production and the adaptation of plants to the environment.

Endoreplication and cell expansion in plants: mechanisms, regulation and function

At the cellular level, the development and growth of all plant organs is based on a common general scheme. After the different cell types are established by formative divisions of stem cells, a stage of cell proliferation occurs in which cells perform the Mitotic Cell Cycle (MCC) to amplify in number. These new cells, initially small and with limited differentiation, begin a period of cell expansion. In this second stage, plant cells usually perform a variety of the cell cycle called Endoreplication (ER), which consists of DNA replication without subsequent mitosis and cytokinesis, generating cells with higher somatic polyploidy, i.e, chromatin content.

As a working hypothesis, we propose that there are multiple mechanisms at the transcriptional and post-transcriptional level in plants that control the transition from the MCC to ER. This occurs both during normal development as well as part of the developmental plasticity mechanisms that plants deploy in response to the environment. Of these mechanisms, some have only been partially characterized and some have yet to be identified. We also propose that the functions of somatic polyploidy generated by ER go beyond promoting cell expansion and that there are still functions that are not fully established and characterized yet.

In this line of research, we aim to study the mechanisms that control ER in plants. In addition, we propose to analyze how the somatic polyploidy generated by this process contributes to the development of different plant organs and the interaction of plants with the environment. We propose to study regulatory networks of transcription factors (TF) that control the transition from MCC to RD and to determine the function of somatic polyploidy in plants by analyzing in detail at the cellular, biochemical, and physiological level plants with modifications in these regulatory pathways.

X: @ramrodri

Selected Publications

SCARECROW-LIKE28 modulates organ growth in Arabidopsis by controlling mitotic cell cycle exit, endoreplication, and cell expansion dynamics. New Phytologist. 237(5):1652-1666. Goldy C, Barrera V, Taylor I, Buchensky C, Vena R, Benfey PN, De Veylder L, Rodriguez RE (2023). DOI: 10.1111/nph.18650

The Arabidopsis GRAS-type SCL28 transcription factor controls the mitotic cell cycle and division plane orientation. PNAS. 9;118(6): e2005256118. Goldy C, Pedroza-Garcia JA, Breakfield N, Cools T, Vena R, Benfey PN, De Veylder L, Palatnik J, Rodriguez RE (2021). DOI: 10.1073/pnas.2005256118

Robust increase of leaf size by Arabidopsis thaliana GRF3-like transcription factors under different growth conditions. Scientific Reports. 8(1):13447. Beltramino M, Ercoli MF, Debernardi JM, Goldy C, Rojas AML, Nota F, Alvarez ME, Vercruyssen L, Inzé D, Palatnik JF, Rodriguez RE. (2018). DOI: 10.1038/s41598-018-29859-9

GIF Transcriptional Coregulators Control Root Meristem Homeostasis. Plant Cell. 30(2):347-359. Ercoli MF, Ferela A, Debernardi JD, Perrone AP, Rodriguez RE, Palatnik JF (2018). DOI: 10.1105/tpc.17.00856

Control of cell proliferation and elongation by miR396. Plant Signal Behav. 11(6): e1184809.Ercoli MF, Rojas AM, Debernardi JM, Palatnik JF, Rodriguez RE (2016). DOI: 10.1080/15592324.2016.1184809

MicroRNA miR396 Regulates the switch between stem cells and transit-amplifying cells in Arabidopsis roots. Plant Cell. 27(12):3354-66. Rodriguez RE*, Ercoli MF, Debernardi JM, Breakfield NW, Mecchia MA, Sabatini M, Cools T, De Veylder L, Benfey PN, Palatnik JF* (2015). DOI: 10.1105/tpc.15.00452

Functional Specialization of the Plant miR396 Regulatory Network through Distinct MicroRNA-Target Interactions. PLoS Genetics. 8(1): 1-14. Debernardi JM*, Rodriguez RE*, Mecchia MA, Palatnik JF. (2012). DOI: 10.1371/journal.pgen.1002419

Control of cell proliferation in Arabidopsis thaliana by microRNA miR396. Development. 137(1): 103-112. Rodriguez RE, Mecchia MA, Debernardi JM, Schommer C, Weigel D, Palatnik JF. (2010).  DOI: 10.1242/dev.043067

For a complete list, check my Google Scholar: https://scholar.google.com/citations?hl=es&user=BkG8J4YAAAAJ