Oxygen supply dictates growth and metabolism in young leaves
Plant Science Research WeeklyWhen thinking of hypoxia or low oxygen in plants, the image that often comes to mind is one of flooding stress. However, it’s not just plants exposed to excess of water that face hypoxia. Even in growing plants, hypoxia sensing and the existence of hypoxic niches play a vital role in their development.…
Review: How plant roots respond to waterlogging
Plant Science Research WeeklyAs the hottest year on record, 2023 has truly been a global annus horribilis during which humans, other animals, and domesticated and wild plants have faced unprecedented environmental challenges. In the past month alone, torrential rainfalls have wreaked havoc in Asia, the Middle East, and many parts…
Plant stem cells under low oxygen: metabolic rewiring by phytoglobin underlies stem cell functionality
Plant Science Research WeeklyWhen flooding occurs, soils become saturated and oxygen solubility and diffusion decreases. This situation creates a hypoxic environment in the roots that stresses the plant, causing significantly decreased growth. However, the quiescent center (QC) stem cells, located in the root apical meristem, are…
TOR couples energy to oxygen sensing to modulate hypoxic gene expression
Plant Science Research WeeklyFloods limit plant oxygen availability, impacting their growth and productivity. In hypoxia, the ERF-VII group of transcription factors are stabilized and activate Hypoxia-Responsive Genes (HRG) that prepare the plant to face the stress. In this situation, plant metabolism switches from oxidative phosphorylation…
The vacuolar H+/Ca transporter CAX1 participates in submergence and anoxia stress responses (Plant Physiol)
Plant Science Research WeeklyCalcium (Ca) signaling is one of the primary plant responses to confront abiotic stresses. To coordinate Ca levels in the different compartments of the cell, several transporters are needed including the H+/Ca exchangers (CAXs) in the tonoplast (vacuolar membrane). While the role of calcium signaling…
Allelic shift in cis-elements of the transcription factor gene RAP2.12 underlies adaptation associated with humidity in Arabidopsis thaliana (Science Adv)
Plant Science Research WeeklyTo better understand plant responses to different environments, Lou et al. compared Arabidopsis thaliana accessions derived from Sichuan (high precipitation/regular flooding) and Tibet (arid) to isolate genetic adaptations towards flooding stress. The two accessions showed divergent phenotypes: the Sichuan…
Anaerobiosis modulation of two phytoglobins in barley (Hordeum vulgare L.), and their regulation by gibberellin and abscisic acid in aleurone cells (Plant Physiol. Biochem)
Plant Science Research Weekly
Barley seeds are anoxic, and during germination pathways are induced to allow energy to be obtained without oxygen. Phytoglobins (Pgb) are hypoxia-induced proteins that are involved in energy metabolism during germination through the Pgb-NO cycle, an alternative pathway to fermentation. In the…
Mitochondrial retrograde signaling through UCP1-mediated inhibition of the plant oxygen-sensing pathway (Curr Biol)
Plant Science Research WeeklyPlants have a plethora of oxygen requiring enzymes that are essential for survival. Mitochondria require oxygen to create ATP, yet during hypoxia they can alter gene expression in the nucleus through retrograde signaling, which may promote stress tolerance. Barreto et al. recently delineated a novel…
Ethylene augments root hypoxia tolerance through amelioration of reactive oxygen species and growth cessation (bioRxiv)
Plant Science Research WeeklyFlooding presents a dual threat to plants; not only is mitochondrial respiration supressed during the resulting hypoxic conditions, but once the floodwaters recede, the return to ambient oxygen levels triggers a cascade of harmful reaction oxygen species (ROS). One of the most well-studied responses…
Phosphatidic acid modulates MPK3- and MPK6- mediated hypoxia signaling in Arabidopsis (Plant Cell)
Plant Science Research WeeklyPlants experience changes in gene expression and cellular metabolism to improve their survival to abiotic stresses, such as hypoxia. It has been observed that environmental signals induce phospholipase D (PLD) which generates phosphatidic acid (PA) by cleaving membrane phospholipids. Indeed, submergence…