HAK5 is a high-affinity potassium transporter that is transcriptionally repressed in high K+ conditions. Zhao et al. identified hormone-related cis-elements in the HAK5 promoter. They screened mutants deficient in transcription factors associated with these cis-elements and found that arf2 mutants show enhanced K+ uptake and root growth on low-K medium, whereas ARF2 overexpression lines showed […]
Questions remain about the evolutionary origins and functions of stomata. They are absent from liverworts, present to a limited extent in mosses, and are found on 410 million year-old fossils of Cooksonia, a leafless plant. Chater et al. show that orthologs of two key transcription factors that control guard cell development in Arabidopsis are expressed […]
Plant cells detect gravity as a consequence of the movement of dense starch granules called statoliths when the statoctyte, the cell that encompasses, them reorients. An open question has been whether the position of the statoliths within the statocyte or the force exerted by them is the primary gravisensing signal. Chauvet et al. designed an […]
Rubisco (Ribulose-1,5-bisphosphate carboxylase / oxygenase) is the enzyme responsible for fixing almost all inorganic carbon into organic form, but it is not optimized for current conditions. As temperature and CO2 levels increase, there is an opportunity to increase photosynthetic efficiency by engineering greater Rubisco efficiency. Sharwood et al. examine the kinetic properties of Rubisco enzymes […]
Gibberellin hormones were famously identified as the product of Gibberella fujikuroi, a fungal pathogen that stimulates host cell elongation, and then subsequently recognized as a hormone produced by plants as well. Fungi and plants produce gibberellins from distinct biochemical pathways, in an example of convergent evolution. Symbiotic rhizobacteria are known to produce gibberellins too. Nett […]
Cells recognize invaders through both cell-surface receptors and intracellular receptors, the latter of which can recognize the invader directly or indirectly, for example through its effects on host proteins. Intracellular surveillance proteins in animals and plants share a core domain, the nucleotide binding domain leucine-rich repeat (NLR) domain. Jones et al. describe similarities and differences […]
Shoot branching increases the photosynthetic surface area and the points at which reproductive structures can form. In angiosperms, auxin (specifically, auxin depletion) has been shown to be involved in the initiation and outgrowth of shoot branches. For example, in apical dominance the primary shoot meristem suppresses bud outgrowth by producing auxin; when the source of […]
“The endosperm is often viewed as a complicated and rather strange tissue” begins this review by Gehring and Satyaki. They go on to describe that the endosperm is the site of expression of imprinted genes, which are genes that are expressed soley when inherited from the mother or father. The authors summarize the unique epigenetic […]
Biofortification is the nutritional enhancement (using conventional or genetic engineering approaches) of food with vitamins or micronutrients with the goal of improving the human diet. A set of new reviews in Current Opinion in Biotechnology summarizes progress towards biofortification of plants to increase their thiamin (vitamin B1), iron and iodine levels. Each article discusses the […]