Entries by Peter Minorsky

Hydraulic Regulation of Stomata in Ferns

Stomatal responses to environmental and endogenous signals in vascular plants are critical for regulating plant gas exchange with the atmosphere. In addition, stomatal closure is vital for minimizing water loss and preventing lethal embolism during drought.  The vast majority of studies concerning stomatal physiology have focused on the angiosperms, where it is well-established that abscisic […]

Auxin Affects Capitulum Pattern Formation

The flower head (capitulum) is a morphological feature that defines the family Asteraceae (the daisy or sunflower family). A typical capitulum consists of many flowers (florets) and phyllaries (modified bracts) compressed into a single structure that mimics a single flower. Capitula commonly have two types of florets: ray and disc florets. Disc florets are usually […]

Insights into the Trans-Golgi Network and Protein Secretion

In eukaryotic cells, the movement of cargo between single membrane-bound organelles such as the endoplasmic reticulum (ER), Golgi apparatus, trans-Golgi network (TGN), endosomes, lysosomes, and vacuoles is mediated by membrane trafficking. At the donor organelle, cargo molecules are loaded into transport vesicles, which then become tethered to and fuse with the target organelle membrane to […]

Advances in Understanding Root Hair Formation

Root hairs greatly increase the surface area of roots, thereby facilitating the uptake of nutrients and water from the rhizosphere. They also serve as sites for plant interactions with soil microorganisms. Thus, elucidation of the molecular pathway for their development is important for potential modification of root hair morphology to produce crops with improved growth […]

The Terpene Synthases of Red Algae Have a Bacterial Origin

The red algae (Rhodophyta), encompassing over 8,000 species, are the richest source of marine secondary metabolites. Among red algae, many genera produce terpenes, which constitute the largest class of secondary metabolites. Despite the rich diversity of terpenes in red algae, little is known about how they are biosynthesized. This is in sharp contrast to our […]

CRISPR Mutants Shed Light on Pectin’s Role in Tomato Fruit Softening

Tomato (Solanum lycopersicum) fruits undergo pronounced softening during ripening. Softening is important for flavor development and overall palatability, but also impacts fruit storage, transportability, and shelf life. Shelf life is a particularly important quality trait of tomato fruits affected by alterations in the cuticle properties of the fruits and the remodeling of fruit cell walls. […]

Hydrogen Cyanide Regulation by S-Cyanylation

Despite its toxicity, cyanide has been proposed to act as a regulator of several biological processes such as seed dormancy and germination, resistance to fungal and viral infection. Arabidopsis null mutants of the mitochondrial enzyme β-CYANOALANINE SYNTHASE (CAS-C1) accumulate cyanide to apparently nontoxic levels, as the plants are completely viable, but show a root hairless […]

Dark-Induced Nuclear Positioning in Leaf Cells

The appropriate spatial arrangement of nuclei is essential for various cellular activities during cell division, growth, migration, and differentiation in eukaryotes. In plants, nuclear positioning is also required for proper responses to environmental stimuli, including pathogen infection, touch, temperature, and light. The nuclei of Arabidopsis (Arabidopsis thaliana) leaf cells move to the anticlinal walls of […]

New Insights into Carboxysomes

Despite its essential role in photosynthetic carbon fixation, ribulose 1,5 bisphosphate carboxylase/oxygenase (Rubisco) is a relatively inefficient enzyme, due in part to its inability to discriminate between CO2 and O2 as substrates. To suppress the oxygenase reaction and enhance the carboxylase activity of Rubisco, cyanobacteria have specialized bacterial microcompartments (BMCs) called carboxysomes that are central […]