Entries by Peter Minorsky

Dynamics of Xylem Water Release

The water transport system of woody plants can experience periods of excessive xylem tension. It is generally assumed that during these times, water stored in capacitive tissue moves into the transpiration stream and buffers the liquid tensions that develop inside the vessel lumen, thereby protecting vessel functionality by reducing the risk of gas emboli formation. […]

Plasmodesmatal Structure and Function

Three types of phloem loading have been defined in plants: 1.) “active apoplasmic” loading, in which sugar transporters are responsible for the active uptake of sugars into the sieve element companion cell complex (SECCC) which is believed to be symplasmically isolated; 2.) “passive symplasmic” loading, in which numerous plasmodesmata (PD) along the phloem-loading pathway enable […]

Identification of Leaf ER Bodies in Arabidopsis

Endoplasmic reticulum bodies (ER bodies) are endoplasmic reticulum-derived organelles specific to the order Brassicales that are thought to play a role in plant defense against biotic factors. ER bodies are generally classified into two types: 1.) constitutive ER bodies that are found in the epidermal cells of seedlings and 2.) wound-inducible ER bodies that are […]

Phosphate Starvation Alters Root Calcium Signatures

Plant roots foraging in the soil have to sense, transduce, and respond to fluctuations in water and nutrients plus a multitude of stresses to which they may be subjected. Biotic and abiotic stresses (including mechanical, salt, osmotic, and oxidative stress) trigger rapid and transient modulations in cytosolic and organellar free Ca2+ in plant cells. Recently, […]

Ethylene and ABA Regulate Ascorbic Acid and Reactive Oxygen Species

The phytohormones ethylene and abscisic acid (ABA) often interact in controlling plant growth and development processes as well as plant responses to stress. The detailed mechanisms underlying the interaction of these two phytohormones, which may act synergistically or antagonistically with each other, is not well understood, especially in regard to the regulation of reactive oxygen […]

The Role of Trigger Factor in Chloroplasts

Chloroplasts contain a small genome that encodes only a minor fraction of approximately 60 to 100 proteins of the entire 3,000 proteins localized in the chloroplast. Chloroplast-encoded proteins, however, are major subunits of important protein complexes involved in gene expression and photosynthesis. The gene expression and biogenesis of plastid proteins is achieved by many components […]

Extracellular ATP-Induced Transcriptome

Transmembrane receptors monitor changes in extracellular ATP concentration in order to detect either the uncontrolled ATP release caused by the necrosis of nearby cells or to instigate active ATP release following pathogen detection. Extracellular ATP can be perceived, therefore, as a sign of damaged self, or a damage-associated molecular pattern (DAMP). In plants, extracellular ATP […]