Genome-Wide Identification and Characterization of Sugar Transporter Genes in Silver Birch

Sugar transporters play an important role in regulating the long-distance sucrose transport from source to sink organs. The main sucrose absorber in woody plants is developing wood. Thus, sucrose transport, regulated by SUT, SWEET, and MST gene families, will determine the formation of woody biomass. Based on silver birch (Betula pendula var. pendula Roth) genomic data, we identified and analyze encoding sugar transporters in Betula pendula. We conducted BLAST-search, phylogenetic, structural analysis and analysis of cis-acting elements of sugar transporter genes and determined their chromosomal localization. We were able to identify and characterize 3 genes of the SUT family, 10 SWEET genes and 36 MST genes, which have a typical number of functional and transmembrane domains for the family. It was shown that silver birch contains a smaller number of sugar transporters genes compared to A. thaliana, which is probably because of the apoplastic type of terminal phloem loading in Arabidopsis, while in silver birch phloem loading is carried out predominantly symplastically. The results obtained may be useful for further study of the participation of sucrose transporters in various biosynthetic processes in woody plants and provide a basis for various biotechnological manipulations.