Tag: Transport and Transporters

Gas exchange and transpiration are regulated by the stomatal aperture, which is itself regulated by the changes in volume of the guard cells that overlay the stomatal pore. When triggered to open, solutes such as K+ and Cl– enter the guard cell through ion transporters, followed osmotically by water;…

In C3 plants at ambient CO2 levels, Rubisco’s oxygenation reaction occurs about once for every three carboxylation reactions. One of the oxygenation products, 2-phosphoglycolate, is rapidly dephosphorylated to glycolate which is toxic and inhibitory to photosynthesis. Glycolate has to be removed from…

Ammonium is one of the major forms in which nitrogen is assimilated. Besides being a nutrient, it also acts as signal that affects gene expression and root system architecture. Some ammonium-induced genes are also induced by low pH (ammonium acidifies the apoplast), whereas others are specifically induced…

To balance nutrient uptake (usually from heterogeneous sources) with nutrient demand, plants use a root-shoot-root signaling pathway. Previously, a root-to-shoot mobile peptide C-TERMINALLY ENCODED PEPTIDE (CEP) was shown to translocate from N-starved roots to the shoot, where it interacts with a leucine-rich…

IN BRIEF by Gregory Bertoni [email protected] Proper localization of proteins in the plasma membrane is critical for proper functioning of plant cells, but the underlying mechanisms are poorly understood (Łangowski et al, 2016). This is especially true for transporter proteins that move necessary…

Casparian strips, named after the German botanist Robert Caspary who discovered them, are a cellular feature found in the roots of all higher plants. They are ring-like lignin polymers deposited in the middle of anticlinal cell walls (parallel to the root radius) between endodermal cells. Along with…

In photosynthesis, light energy generates proton motive force (pmf) across the thylakoid membrane. The establishment and maintenance of pmf involves numerous membrane transporters as well as other ions.  Szabò and Septea review how various ions (including K+, Na+, Fe2+, Cu+, Mn2+, Ca2+, Cl–) contribute…

Which arose first during evolution- a metabolite molecule or a transporter that could move it across a membrane?  Jørgensen et al. studied transporters for glucosinolate defense molecules in Brassicales species.  Glucosinolates are derived from the broad class of cyanogenic glucosides, and glucosinolates…