Moving around taught me two essential skills, only one being relevant here: how to put up wallpaper, and how critical it is to label boxes to help the moving company drop them at their intended location. Now think of a cell: the boxes are vesicles, their contents are proteins and metabolites, and the starting location […]
When I was a kid, I remember keeping a bottle of wite-out with my pens for the inevitable spelling mistake. Now, in the digital age, I either let my word processor autocorrect spelling errors or wait for the red squiggly line under suspicious words. On any given day, a single (plant) cell by far out-writes […]
Plants have veins too. As in animals, the plant vasculature facilitates the circulation of water and nutrients across tissues and organs. Unlike animals, it originates from a self-renewing population of meristematic cells forming the (pro)cambium ring within stems and tree trunks and roots. Local signals nudge freshly divided cells toward phloem xylem or procambium cell […]
Arabidopsis thaliana seedlings exposed to heat stress (>42ºC) suffer high lethality rates unless exposed to milder heat (37ºC) beforehand. This pre-exposure distinguishes basal from acquired thermotolerance and has been extensively studied over the years. However, experimental conditions used to study responses to elevated temperatures do not always adhere to a standard protocol and can vary […]
Plants have armed themselves with a battalion of photoreceptors to cope with changes in light quantity, quality and direction. Light perception is especially critical when the seedling first emerges from the darkness of the soil and engages the red/far-red light photoreceptors phytochromes (phys). An avalanche of genetic screens has fleshed out phy signaling cascade over […]
Modern-day chloroplasts are the descendants of a photosynthetic cyanobacterium that took up residence inside the cytoplasm of a eukaryotic cell. Since this initial cohabitation agreement, the cyanobacterial endosymbiont has dumped most of its genome into the host eukaryotic genome. This creates an engineering nightmare: how do proteins, translated in the cytosol by the host ribosomes […]
The discovery of Mediator began with the observation that two transcriptional activators could interfere with each other’s function in vitro, even though they did not bind to the same promoter (Kelleher, Flanagan and Kornberg, 1990). The hypothesis, since then well-validated, was that each transcription factor titrates components (i.e., Mediator) critical for the proper initiation of […]
Plants can adjust their growth and reproduction cycles according to the local climate they experience, but how will they respond when ambient temperatures rise? Most Arabidopsis accessions respond by increasing cell elongation and accelerated flowering, but some cannot cope with higher temperatures and stop growing. Such was the premise that led to the cloning of […]
Brassinosteroids (BR) are the only plant hormones with an animal counterpart: steroid hormones. Analysis of BR signaling demonstrated that steroid receptors could reside at the plasma membrane and modulate growth and gene expression, an observation that is now becoming appreciated in non-plant systems (Levin and Hammes, 2016). Our understanding of BR signaling in Arabidopsis thaliana […]