Research illuminates new element of plant immune defense response to biotic stress

August 26, 2020

Plants are at the mercy of many stresses, both abiotic, such as drought and heat, and biotic, such as pathogens. Researchers know that the plant immune system often responds to infection with an increased cytosolic calcium concentration, which activates immune response regulators. Previous research has studied the cytosolic calcium response in Physcomitrella patens (a moss plant often used in studies) as a result of abiotic stress but until recently scientists have not explored the relationship between cytosolic calcium response, P. patens, and biotic stress.

A collaboration between scientists with the Vidali at Worcester Polytechnic Institute and the Centro de Biotecnología y Genómica de Plantas in Madrid resulted in the first article addressing the involvement of cytosolic calcium oscillations and waves in the immune response of P. patens to a biotic stress. Specifically, the scientists administered chitin oligosaccharides to simulate a fungal infection.

"The results of the study show that, following exposure to chitin oligosaccharides, cytosolic calcium oscillations propagate across the whole plant," Vidali explained. "Interestingly, the frequency of the cytosolic calcium oscillations increases to a fixed value with the increase in the concentration of administered chitin oligosaccharides. This immediate cytosolic calcium response is an early mediator of the plant immune response to fungi."

This result suggests that chitin-triggered calcium oscillations are conserved and were likely present in the common ancestor of mosses and vascular plants. "Remarkably, the chitin oligosaccharide treatment causes the dissipation of the apical actin filaments and inhibition of cell growth," said Vidali. Additionally, their research showed that the cytosolic calcium influx affected transcription of defense-related genes, meaning that this oscillation could influence gene expression and allow the plant to mount a defense response to attacking pathogens.

Vidali and his team found that the cytosolic calcium signal originating in each individual cell becomes synchronized, resulting in the cytosolic calcium of the plant pulsating as a whole. This suggests that there may be a mechanism of cytosolic calcium-dependent communication between cells, which allows for a uniform response. This observation opens interesting new lines of investigation in cell-to-cell communication and signaling in plants.

"For us to increase plant resistance to biotic stress, it is necessary to understand the molecular mechanisms related to immune plant response. This paper gets us closer to understanding, widely distributed, and evolutionarily conserved responses to biotic stress," Vidali concludes. Read more in "Physcomitrella patens." There will be a free live presentation on this research held on September 29. -end-

American Phytopathological Society

Related Immune Response Articles from Brightsurf:

Boosting chickens' own immune response could curb disease
Broiler chicken producers the world over are all too familiar with coccidiosis, a parasite-borne intestinal disease that stalls growth and winnows flocks.

Cells sacrifice themselves to boost immune response to viruses
Whether flu or coronavirus, it can take several days for the body to ramp up an effective response to a viral infection.

Children's immune response more effective against COVID-19
Children and adults exhibit distinct immune system responses to infection by the virus that causes COVID-19, a finding that helps explain why COVID-19 outcomes tend to be much worse in adults, researchers from Yale and Albert Einstein College of Medicine report Sept.

Which immune response could cause a vaccine against COVID-19?
Immune reactions caused by vaccination can help protect the organism, or sometimes may aggravate the condition.

Obesity may alter immune system response to COVID-19
Obesity may cause a hyperactive immune system response to COVID-19 infection that makes it difficult to fight off the virus, according to a new manuscript published in the Endocrine Society's journal, Endocrinology.

Immune response to Sars-Cov-2 following organ transplantation
Even patients with suppressed immune systems can achieve a strong immune response to Sars-Cov-2.

'Relaxed' T cells critical to immune response
Rice University researchers model the role of relaxation time as T cells bind to invaders or imposters, and how their ability to differentiate between the two triggers the body's immune system.

A novel mechanism that triggers a cellular immune response
Researchers at Baylor College of Medicine present comprehensive evidence that supports a novel trigger for a cell-mediated response and propose a mechanism for its action.

Platelets exacerbate immune response
Platelets not only play a key role in blood clotting, but can also significantly intensify inflammatory processes.

How to boost immune response to vaccines in older people
Identifying interventions that improve vaccine efficacy in older persons is vital to deliver healthy ageing for an ageing population.

Read More: Immune Response News and Immune Response Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to