2. Cellular bases of interaction between growth and defense

One of the main consequences of pathogen infection is that it disturbs the metabolism of the host plant, including protein synthesis. The work of Xinnian Dong, professor of Biology at Duke University (USA), has shown that plants have a circadian clock that directly controls defense signaling and the expression of genes that anticipate pathogen infection at the time of day when the risk of infection is highest.

“Under immune induction, the circadian clock programs the immune response to avoid conflicting with other physiological processes like transporting water at night. Plus, precipitation changes regulate the plant’s circadian clock to influence various physiological processes like effector-triggered immunity,” she explained.

One important aspect of plants is that they seem to have DNA-repair pathways that are much more efficient than those found in mammals, as highlighted Arp Schnittger, professor at the University of Hamburg.

In this regard, retinoblastoma plays an essential role. This multi-function regulator participates in cell proliferation, development decisions, response to stress and maintaining the integrity of the genome. This is why it is currently the focus of study, as it could provide keys to identifying other ways plants regulate DNA damage.

The cell wall is another structure being analyzed, as explained Clara Sánchez-Rodríguez, assistant professor at the ETH Institute in Zürich. This is because, in addition to providing the plant with stability and protection, it is the first layer that perceives stimuli. For this reason, controlled changes to the structure are essential to the plant adapting its growth to the stresses from its environment.