Mystery unveiled for an exploration into the mysteries of cell growth

Plants resistant to a key inhibitor, with a strong influence on the process of cell growth, have been discovered by a team from BIAM. This is an asset for a better understanding of plant growth regulation, with potential implications in both the food security sector and the treatment of inflammatory diseases and cancers.

The study of kinases, which are present in organisms as diverse as humans and plants, provides a universal approach to better understand diseases related to cell proliferation dysregulation. Kinases are crucial players in cellular activity, involved into signaling cascades. To better comprehend the role of kinases in this complex functioning, scientists investigate the inherent reactions of kinases and the associated cellular consequences when exposed to inhibitors (pharmacological molecules that selectively neutralize the action of their target). Benoît Menand and Marie-Hélène Montané, researchers at BIAM, are particularly studying the TOR kinase (Target of Rapamycin), which could be defined as the true conductor of cell proliferation and cellular differentiation.

To demonstrate this, scientists had to investigate the action of the inhibitor AZD-8055 at the whole plant level.

 To do so, they selected plants resistant to this inhibitor in order to measure growth markers associated with this resistance, such as root development, photosynthesis activity, and the phosphorylation (see Box) of target proteins. The result of these measurements was unequivocal, confirming the regulatory role of the TOR kinase on these processes. “It is important to keep in mind that TOR, like many kinases, is present in both plant and animal cells, where it performs a similar function. The pharmacogenetic approach we have developed in plants is likely valid for animal cells or algae. This discovery is therefore crucial for various research sectors,” emphasize the scientists unanimously.

Indeed, understanding these fundamental mechanisms promotes research into strategies for adapting plant growth to diseases and environmental stress. However, the outcome and impact of these studies, employing a pharmacogenetic approach, do not stop there: unveiling the mysteries of TOR kinase activity regulation could also help advance research on treatments for various forms of cancer or inflammatory diseases. Yet another significant example of the importance of supporting fundamental research.

La phosphorylation is a process carried out by kinases, which transfer a phosphate group from a molecule to a targeted protein, thereby modifying its structure and activating or repressing its function within the cell.

Phosphorylation can trigger a cascade of cellular reactions, activating or repressing specific proteins to regulate biological processes such as cell growth, metabolism, intercellular communication, and even the response to hormones or growth factors.