Plant development is modulated by the convergence of multiple environmental and endogenous signals, and the mechanisms that allow the integration of different signaling pathways is currently being unveiled. A paradigmatic case is the concurrence of brassinosteroid (BR) and gibberellin (GA) signaling in the control of cell expansion during photomorphogenesis, which is supported by physiological ...

Continued genetic screening and analysis of Arabidopsis mutants has extended our view of brassinosteroid signaling beyond hormone perception to downstream events involving a negative cytoplasmic regulator and nuclear localized positive activators of the brassinosteroid response.

Multiple mechanisms have been described for coordination of responses to the plant hormones auxin and brassinosteroids (Zhang et al., 2009). One unexplained phenomenon is the reliance of the auxin transcriptional response on a functional brassinosteroid pathway. In this study, we used luciferase reporters to interrogate the promoter of SMALL AUXIN-UP RNA15 (SAUR15), a well-characterized auxin a...

Brassinosteroids (BRs) regulate multiple aspects of plant growth and development and require an active BRASSINOSTEROID-INSENSITIVE1 (BRI1) and BRI1-ASSOCIATED RECEPTOR KINASE1 (BAK1) for hormone perception and signal transduction. Many animal receptor kinases exhibit ligand-dependent oligomerization followed by autophosphorylation and activation of the intracellular kinase domain. To determine ...

Brassinosteroids (BRs) are essential growth-promoting hormones that regulate many aspects of plant growth and development. Two leucine-rich repeat receptor-like kinases (LRR-RLKs) are involved in BR perception and signal transduction: brassinosteroid insensitive 1 (BRI1), which is the BR receptor, and its coreceptor BRI1-associated kinase 1 (BAK1). Both proteins are classified as serine/threoni...

Outside of mammals, two model systems have been the focus of intensive genetic studies aimed at defining the molecular mechanisms of steroid hormone action—the flowering plant, Arabidopsis thaliana, and the fruit fly, Drosophila melanogaster. Studies in Arabidopsis have benefited from a detailed description of the brassinosteroid (BR) biosynthetic pathway, allowing the effects of mutations to b...

Non-volatile sesquiterpenoids, a trichothecene family of phytotoxins such as deoxynivalenol (DON) and T-2 toxin, contain numerous molecular species and are synthesized by phytopathogenic Fusarium species. Although trichothecene chemotypes might play a role in the virulence of individual Fusarium strains, the phytotoxic action of individual trichothecenes has not been systematically studied. To ...

Leaf morphology, particularly in crop, is one of the most important agronomic traits because it influences the yield through the manipulation of photosynthetic capacity and transpiration. To understand the regulatory mechanism of leaf morphogenesis, an Oryza sativa dominant mutant, rolled and erect leaf 1 (rel1) has been characterized. This mutant has a predominant rolled leaf, increased leaf a...

Plant GSK3-like kinases are key regulators that modulate a broad range of physiological processes such as cell growth, stomatal and flower development, responses for abiotic and biotic stress, and carbohydrate metabolism. Arabidopsis Shaggy/GSK3-like kinases (AtSK) consist of ten members that are classified into four subfamilies (I∼IV). Only one of these Arabidopsis GSK3s, BIN2 (also named AtSK...

In plants, LRR-RLKs play central roles in regulating perception of extracellular signals and initiation of cellular responses under various environmental challenges. Arabidopsis SERK genes, including SERK1 to SERK5, constitute a LRR-RLK sub-family. SERK1, SERK2, SERK3/BAK1, and SERK4/BKK1 have been well characterized to function as crucial regulators in multiple physiological processes such as ...