It was recently discovered that the F-box protein from the complex SCFTIR1 is a receptor for them. PIN proteins regulate their efflux, and they cause miscarriages and leukemia, as evinced by 2,4-D and 2,4,5-T, two of them in 
It was recently discovered that the F-box protein from the complex SCFTIR1 is a receptor for them. PIN proteins regulate their efflux, and they cause miscarriages and leukemia, as evinced by 2,4-D and 2,4,5-T, two of them in Agent Orange. Also responsible for parthenocarpy, they activate expansins in one of their main functions. In low concentrations, they can delay flower senescence. Featuring prominently in the acid growth hypothesis, and competing with cytokinins in apical dominance, for 10 points, name this class of plant growth hormones.
It was recently discovered that the F-box protein from the complex SCFTIR1 is a receptor for them.