SWEET11b transports both sugar and cytokinin in developing barley grains

• DOI: 10.1093/plcell/koad055
• Publication Date: 2023-03-01T18:20:06Z
• Authors: Volodymyr Radchuk; Zeinu M Belew; Andre Gündel; Simon Mayer; Alexander Hilo; Goetz Hensel; Rajiv Sharma; Kerstin Neumann; Stefan Ortleb; Steffen Wagner; Aleksandra Muszynska; Christoph Crocoll; Deyang Xu; Iris Hoffie; Jochen Kumlehn; Joerg Fuchs; Fritz F Peleke; Jedrzej J Szymanski; Hardy Rolletschek; Hussam H Nour-Eldin; Ljudmilla Borisjuk
• Keywords: Genetically modified rice; Hordeum

Abstract Even though Sugars Will Eventually be Exported Transporters (SWEETs) have been found in every sequenced plant genome, a comprehensive understanding of their functionality is lacking. In this study, we focused on the SWEET family barley (Hordeum vulgare). A radiotracer assay revealed that expressing HvSWEET11b African clawed frog (Xenopus laevis) oocytes facilitated bidirectional transfer not only just sucrose and glucose, but also cytokinin. Barley plants harboring loss-of-function mutation could set viable grains, while distribution cytokinin was altered developing grains which gene knocked down. Sucrose allocation within transgenic disrupted, consistent with changes to gradient across as visualized by magnetic resonance imaging Fourier transform infrared spectroscopy microimaging. Decreasing expression reduced overall grain size, sink strength, number endopolyploid endosperm cells, contents starch protein. The control exerted over sugars cytokinins likely predetermines synergy, resulting adjustments grain's biochemistry transcriptome.