Tag: Signals and Responses

Green Fluorescent Protein (GFP) is a widely-used reporter with which to analyze protein localization and expression levels. De Jonge et al. report that GFP fluorescence is greatly diminished in the presence of the hormone salicylic acid (SA), as is the fluorescence of the reporters RFP and VENUS. The…

Stomatal defense, recognition of pathogens at the stomatal pore accompanied by stomatal closure to prevent their entry, was discovered ten years ago. Melotto et al. review what we’ve learned in the past decade about this key defense strategy. They discuss pathogen recognition, in which microbe-associated…

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…

Based on various developmental, environmental, and hormonal cues, proplastids can be converted into different types of plastids within cells. In Arabidopsis, chloroplast development is repressed in roots via auxin signaling. When roots are detached from the shoot, and its supply of auxin, roots develop…

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…

Many of the genes involved in the phosphate-stress response (PSR) have been identified from plants growing on sterile medium.  Castrillo et al. examined how the root microbiota affectthe phosphate stress response, and how phosphate affects the association between roots and microbes.  Plants deficient…

Previously, the rice PLA1 gene encoding a CYTOCHROME P450 (CYP78A) was shown to increase vegetative growth. Sun et al. enhanced expressed maize PLA1 specifically in the leaf growth zone under the control of the GA2ox promoter. Transgenic plants produced larger leaves and larger seed yields than control…

Capua and Eshed explored the link between auxin and leaf initiation at the shoot apical meristem, using the tomato mutant leafless (lfs), which is an ortholog of the Arabidopsis DORNRONSCHEN (DRN) and DRN-like (DRNL) genes that encode AP2-type transcription factors. The lfs mutant and the drn/drnl double…