Plant & zo
The science of plants and more
Grip on DNA
For plants that reproduce trough flowering, a proper formation of these flowers is essential. One of the important proteins in this process is LEAFY, a gene on/off switching protein. LEAFY regulates genes needed for flower formation. LEAFY can turn on some of these by itself, but for others LEAFY needs a helping hand. One of these helpers is UFO. Long, it was unclear how UFO helps LEAFY because UFO is not a gene on/off switching protein itself. But now researchers from France have found out how UFO helps LEAFY
UFO has one clearly identifiable domain: an F-box. As a rule proteins with an F-box are part of the labelling machine that marks proteins for degradation. UFO is even part of those F-box proteins for which this function was deciphered. Not strange to think that the help that UFO gives LEAFY is in the form of labelling proteins for degradation. But this turned out not to be the case.
The researchers analysed if the F-box part of the UFO protein was needed for the help that UFO gave LEAFY. UFO and LEAFY together turn on the genes for which UFO is needed, without UFO LEAFY could not switch those genes on. But UFO without its F-box helped LEAFY just as well as. The F-box was not needed, UFO was not helping through marking genes for degradation
UFO is literary helping LEAFY to get grip on the DNA
But what was UFO doing to help LEAFY. To find out, the researchers zoomed in on the region of the gene were the binding of gene on/off switches takes places. Here they observed that UFO, but not LEAFY bound to the DNA, although LEAFY is needed to turn on the genes. The binding of UFO to the DNA was depended on the nucleotide order. Changing this caused UFO to no longer bind to the DNA. Therefore, UFO was needed for LEAFY to bind to the UFO-specific regions on the DNA
UFO is literary helping LEAFY to get grip on the DNA of the genes they turn on together. In this way UFO helps LEAFY to distinguish between the genes it can turn on. Making it possible that a single master switch like LEAFY can be responsible for the formation of something so complex like a flower.
Philippe Rieu, Laura Turchi, Emmanuel Thévenon, Eleftherios Zarkadas, Max Nanao, Hicham Chahtane, Gabrielle Tichtinsky, Jérémy Lucas, Romain Blanc-Mathieu, Chloe Zubieta, Guy Schoehn & François Parcy (2023) The F-box protein UFO controls flower development by redirecting the master transcription factor LEAFY to new cis-elements. Nature Plants. https://doi.org/10.1038/s41477-022-01336-2