Plants’ reaction to stress

A study conducted at the University of Seville and led by researcher Emilio Gutiérrez, from the Department of Plant Biochemistry and Molecular Biology, has provided new data to understand how plants manage stressful situations. These living organisms’ ability to adapt to different adverse conditions determines, to a large extent, their survival. Therefore, understanding how they are able to respond to and cope with stressful conditions is crucial to design biotechnological approaches to minimise economic losses in agriculture caused by an ever-changing climate. 

At the cellular level, one of the first events to occur after the perception of the stress signal is the formation of cytoplasmic complexes composed of RNA and proteins known as stress granules. The formation of these complexes occurs as a defence mechanism to promote cell survival. Although the function of stress granules is well studied in mammals, their role in plants is still unknown. In a paper published in 2015 in the journal The Plant Cell, it was found that the TSN protein acts as a connector between stress granule assembly and plant resistance. However, the molecular mechanism through which the TSN protein performs this function is unknown. 

Recently, US researcher Emilio Gutiérrez discovered that TSN acts as a scaffolding protein by recruiting, through a highly disordered region, numerous protein components, including proteins previously localised in stress granules in other study models. Furthermore, the study showed that TSN’s scaffolding role is crucial to the architecture and function of stress granules. Among the plant-specific components identified was SnRK1 kinase, a central sensor in the cellular response to environmental and nutritional stresses. The study demonstrated that both the localisation of SnRK1 in stress granules and its interaction with TSN are crucial to its activation. The activation of SnRK1 could trigger the molecular response mechanisms to the imposed stress situation, thus allowing cell survival and thus survival of the organism itself. The paper shows for the first time how stress granule formation interferes with SnRK1-induced signalling, one of the most studied cellular pathways in eukaryotes.

The study was carried out with funding from the European Research Council (Marie Curie programme Individual fellowships), from the Ministry of Science and Innovation (Juan de la Cierva programme Incorporation) and the University of Seville’s own research plan, and represents the beginning of a new line of research led by Professor Emilio Gutiérrez Beltrán, which has recently been funded by the Ministry of Science and Innovation.

The printed version of this article was issued on 1st September 2021, although an online version was available since 21st July.