Glenn et al. introduce a new method for the labeling and purification of newly-synthesized proteins from intact tissues. The method, named BONCAT (Bioorthogonal Non-Canonical Amino Acid Tagging) involves the incorporation of the non-canonical methionine surrogate azidohomoalanine (Aha) into newly synthesized proteins. Aha has a reactive azide side chain that can be conjugated for instance to […]
Continuing the theme of peptide signaling, Stegmann et al. showed that a subset of the RALF (RAPID ALKALINIZATION FACTOR) family of plant peptides can negatively regulate plant immune responses. When plants are treated with flg22, a peptide epitope of bacterial flagellin, they produce reactive oxygen species (ROS) as part of their defense response. The flg22 […]
The Casparian strip is a permeability barrier that seals the spaces between root endodermis cells and so prevents bulk-flow uptake of solutes. Previously, a leucine-rich repeat receptor kinase called SCHENGEN3 or GASSHO1 (GSO1/SGN3) was identified as necessary for normal Casparian strip formation. Now, two papers in Science show that the interaction between diffusible peptides and […]
Powdery mildew disease is a broad term that encompasses more than 650 species of powdery mildew fungi that affect about 10,000 plant species, with serious economic consequences. In the 1930s/40s, broad-spectrum resistance to powdery mildew was found in barley with a loss-of-function of the Mildew resistance locus o (Mlo) gene. Subsequently, resistance conferred by induced […]
The interaction between angiosperms and their pollinators provides an excellent system to study co-evolution, and underpins the evolution of the biosynthesis of numerous interesting and useful specialized metabolites, from pigments to fragrances. Borghi et al. review the metabolic pathways that produce these signals and rewards for pollinators. Classes of compounds discussed in terms of synthesis […]
IN BRIEF: Nancy R. Hofmann [email protected] Plant development and responses to the environment hinge on the ability to target proteins to different areas of the plasma membrane within a cell. Indeed, the establishment of polar distributions of proteins such as PIN auxin transporters is among the key responsibilities of the endomembrane trafficking system (reviewed in […]
Magnaporthe oryzae is the fungus that causes rice blast disease, which is a serious threat to food security. Ortiz et al. explore the interaction between AVR-Pia, a fungal effector protein, and RGA5, a rice NLR (nucleotide-binding domain and leucine-rich repeat protein) immune receptor protein. RGA5 has a C-terminal domain, RATX1, that acts as an integrated […]
Several studies have implicated microRNAs in plant defenses against pathogens. Wu et al. previously showed that virus resistance is facilitated by the interaction of viral-inducible AGO18 (which is cleavage-inactive) and rice miR528. In this work, they identified the role of miR528 in viral resistance. Rice susceptibility to rice-stripe virus is positively correlated with miR528 expression […]
Students learn that membrane proteins are inserted into the endoplasmic-reticulum (ER) membrane co-translationally, but this mechanism does not hold for so-called tail-anchored (TA) proteins which carry a single C-terminal membrane spanning domain and insert into the ER membrane post-translationally. The mechanism of TA protein insertion was recently described in yeast as the GET (Guided Entry […]