Heat stress in plants: sensing, signalling and ferroptosis.

In the current context of global warming, high temperature events are becoming more frequent and intense in many places around the world. In this context, understanding how plants sense and respond to heat is essential to develop new tools to prevent plant damage and address global food security, as high temperature events are threatening agricultural sustainability. This review summarizes and integrates our current understanding underlying the cellular, physiological, biochemical and molecular regulatory pathways triggered in plants under moderately high and extremely high temperature conditions.

Chitosan microparticles mitigate nitrogen deficiency in tomato plants.

Nitrogen (N) deficiency is one of the most prevalent nutrient deficiencies in plants, and has a significant impact on crop yields. In this work we aimed to develop and evaluate innovative strategies to mitigate N deficiency. We studied the effect of supplementing tomato plants grown under suboptimal N nutrition with chitosan microparticles (CS-MPs) during short- and long-term periods.

Overexpression of Arabidopsis aspartic protease APA1 gene confers drought tolerance.

Drought is an environmental stress that severely affects plant growth and crop production. Different studies have focused on drought responses but the molecular bases that regulate these mechanisms are still unclear. We report the participation of Aspartic Protease (APA1) in drought tolerance.

Chitosan microparticles improve tomato seedling biomass and modulate hormonal, redox and defense pathways.

Agrobiotechnology challenges involve the generation of new sustainable bioactives with emerging properties as plant biostimulants with reduced environment impact. We analyzed the potential use of recently developed chitosan microparticles (CS-MP) as growth promoters of tomato which constitutes one of the most consumed vegetable crops worldwide. Treatments of tomato seeds with CS-MP improved germination and vigor index.

Regulation of SCF E3 ligase assembly by S-nitrosylation of Arabidopsis SKP1-like1 impacts on auxin signaling.

The F-box proteins (FBPs) TIR1/AFBs are the substrate recognition subunits of SKP1-cullin-F-box (SCF) ubiquitin ligase complexes and together with Aux/IAAs form the auxin co-receptor. Although tremendous knowledge on auxin perception and signaling has been gained in the last years, SCF complex assembly and stabilization are emerging as new layers of regulation. Here, we investigated how nitric oxide (NO), through S-nitrosylation of ASK1 is involved in SCF assembly.

The DC1-domain protein VACUOLELESS GAMETOPHYTES is essential for development of female and male gametophytes in Arabidopsis.

In this work we identified VACUOLELESS GAMETOPHYTES (VLG) as a DC1 domain-containing protein present in the endomembrane system and essential for development of both female and male gametophytes. VLG was originally annotated as a gene coding for a protein of unknown function containing DC1 domains. DC1 domains are cysteine- and histidine-rich zinc finger domains found exclusively in the plant kingdom that have been named on the basis of similarity with the C1 domain present in protein kinase C (PKC).

Heat stress induces ferroptosis-like cell death in plants.

In plants, regulated cell death (RCD) plays critical roles during development and is essential for plant-specific responses to abiotic and biotic stresses. Ferroptosis is an iron-dependent, oxidative, nonapoptotic form of cell death recently described in animal cells. In animal cells, this process can be triggered by depletion of glutathione (GSH) and accumulation of lipid reactive oxygen species (ROS).

oiwa, a female gametophytic mutant impaired in a mitochondrial manganese-superoxide dismutase, reveals crucial roles for reactive oxygen species during embryo sac development and fertilization in Arabidopsis.

Reactive oxygen species (ROS) can function as signaling molecules, regulating key aspects of plant development, or as toxic compounds leading to oxidative damage. In this article, we show that the regulation of ROS production during megagametogenesis is largely dependent on MSD1, a mitochondrial Mn-superoxide dismutase. Wild-type mature embryo sacs show ROS exclusively in the central cell, which appears to be the main source of ROS before pollination.