Entries by Peter Minorsky

A Molecular Gatekeeper of Algal Biofuel Synthesis

Algae undergo a complete metabolic transformation under stress by arresting cell growth, inducing autophagy, and hyper-accumulating biofuel precursors such as triacylglycerols and starch. However, the regulatory mechanisms behind this stress-induced transformation are still unclear. Understanding the signaling mechanism behind growth, starvation, and starvation-related responses is critical to the successful development of algal biofuels.  Phosphatidylinositol 3-kinase (PI3K) signaling […]

Low Xylem Vulnerability in Oaks

Under conditions of drought stress, the continuous column of water in the plant xylem experiences increasing tension caused by declining water potential at the sites of evaporation. Eventually, air is drawn into the water transport system, forming embolisms in the xylem conduits. Although plants have developed several mechanisms to restore vessel functionality by refilling embolized vessels, those […]

New Insights into the Molecular Biology of Plant Circadian Rhythms

The circadian clock is an endogenous timekeeper that synchronizes essential biological processes with the outside world. Eukaryotic clocks rely on the ubiquitin proteasome system to target core clock factors for degradation. Altering clock protein degradation can change the period length of the clock. The ubiquitin proteasome system is an enzymatic pathway that mediates the covalent attachment of […]

Selective Chloroplast Microautophagy

When plants are exposed to excessive light, photoinhibition occurs and chloroplasts become damaged. Photodamaged chloroplasts undergo vacuolar digestion through a poorly understood autophagic process called chlorophagy.  In general, cell biologists recognize two types of autophagy: macroautophagy and microphagy.   Macroautophagy is a form of autophagy in which a membrane forms around the material to be digested before […]

ABA Biosynthesis Occurs in the Mesophyll

The plant hormone abscisic acid (ABA) plays a critical role in enhancing plant survival during water deficit. While there is no doubt that ABA is a carotenoid derivative and that carotenoid cleavage occurs in the chloroplast, uncertainty remains about which tissues are responsible for synthesizing ABA. McAdam and Brodribb (10.1104/pp.17.01829) review and critique recent molecular […]

How Does a Plant Tolerate Prolonged Darkness?

The exposure of plants to prolonged darkness leads to the exhaustion of starch reserves and carbon and energy starvation. In such cases, plants must use alternative nutrient and energy sources to survive. Autophagy is an important mechanism that breaks down proteins and lipids and thereby provides the cell with alternative carbon, nitrogen, and energy during starvation. […]

Intra-Organ Regulation of Shade Responses 

Plants beneath a canopy compete with neighboring plants for light by triggering various physiological responses, collectively known as shade avoidance syndrome. Because of the selective absorption of red (R) light by plants in the upper canopy, plants in the shade are exposed to low R to far-red (FR) light ratios. Phytochrome, which absorbs R (660 […]

A MicroRNA Regulating Lateral Root Growth in Response to Salt

Soil salinity is a major threat to crop yields around the world. Salt generally damages plants through osmotic stress in the rhizosphere, interfering with water and nutrient uptake and causing cells to be subjected to ionic toxicity Developmental plasticity in the root system is an important strategy allowing plants to cope with environmental stresses including salinity. […]

Drugs Triggering Oil Accumulation in a Diatom

Oils composed of triacylglycerols (TAGs) have a broad range of applications, ranging from foods to biofuels. Microalgae are promising feedstocks for the production of (TAGs) but obtaining high yields of TAGs is challenging. Conte et al. (10.1104/pp.17.01804) have developed a phenotypic assay for the accumulation of oil droplets in the diatom Phaeodactylum tricornutum. They have […]