Interdependent Nutrient Availability and Steroid Hormone Signals Facilitate Root Growth Plasticity.

Plants acquire essential elements from inherently heterogeneous soils, in which phosphate and iron availabilities vary. Consequently, plants have developed adaptive strategies to cope with low iron or phosphate levels, including alternation between root growth enhancement and attenuation. How this adaptive response is achieved remains unclear.

High Resolution Quantification of Crystalline Cellulose Accumulation in Arabidopsis Roots to Monitor Tissue-specific Cell Wall Modifications.

Plant cells are surrounded by a cell wall, the composition of which determines their final size and shape. The cell wall is composed of a complex matrix containing polysaccharides that include cellulose microfibrils that form both crystalline structures and cellulose chains of amorphous organization. The orientation of the cellulose fibers and their concentrations dictate the mechanical properties of the cell.

Translatome analyses capture of opposing tissue-specific brassinosteroid signals orchestrating root meristem differentiation.

The mechanisms ensuring balanced growth remain a critical question in developmental biology. In plants, this balance relies on spatiotemporal integration of hormonal signaling pathways, but the understanding of the precise contribution of each hormone is just beginning to take form. Brassinosteroid (BR) hormone is shown here to have opposing effects on root meristem size, depending on its site of action.

Root growth is modulated by differential hormonal sensitivity in neighboring cells.

Coherent plant growth requires spatial integration of hormonal pathways and cell wall remodeling activities. However, the mechanisms governing sensitivity to hormones and how cell wall structure integrates with hormonal effects are poorly understood. We found that coordination between two types of epidermal root cells, hair and nonhair cells, establishes root sensitivity to the plant hormones brassinosteroids (BRs).

Brassinosteroid perception in the epidermis controls root meristem size.

Multiple small molecule hormones contribute to growth promotion or restriction in plants. Brassinosteroids (BRs), acting specifically in the epidermis, can both drive and restrict shoot growth. However, our knowledge of how BRs affect meristem size is scant.

Protein flexibility acclimatizes photosynthetic energy conversion to the ambient temperature.

Adjustment of catalytic activity in response to diverse ambient temperatures is fundamental to life on Earth. A crucial example of this is photosynthesis, where solar energy is converted into electrochemical potential that drives oxygen and biomass generation at temperatures ranging from those of frigid Antarctica to those of scalding hot springs. The energy conversion proceeds by concerted mobilization of electrons and protons on photoexcitation of reaction centre protein complexes.

A novel high-affinity arginine transporter from the human parasitic protozoan Leishmania donovani.

We describe the first functional and molecular characterization of an amino acid permease (LdAAP3) from the human parasitic protozoan Leishmania donovani, the causative agent of visceral leishmaniasis in humans. This permease contains 480 amino acids with 11 predicted trans-membrane domains. Expressing LdAAP3 in Saccharomyces cerevisiae mutants revealed that LdAAP3 codes for a high-affinity arginine transporter (Km 1.

Differentiation of Leishmania donovani in host-free system: analysis of signal perception and response.

Leishmania donovani are the causative agents of kala-azar in humans. They undergo a developmental program following changes in the environment, resulting in the reversible transformation between the extracellular promastigote form in the sand fly vector and the obligatory intracellular amastigote form in phagolysosomes of macrophages. A host-free differentiation system for L.