Structure, phylogeny, allelic haplotypes and expression of sucrose transporter gene families in Saccharum

摘要: Sugarcane is an economically important crop contributing to about 80 % of the world sugar production. Increasing efforts in molecular biological studies have been performed for improving yield and other relevant agronomic traits. However, due sugarcane’s complicated genomes, it still challenging study genetic basis traits, such as sucrose accumulation. Sucrose transporters (SUTs) are critical both phloem loading source tissue uptaking sink tissue, considered be control points regulating storage. no genomic sugarcane transporter (SsSUT) families has reported up date. By using comparative genomics bacterial artificial chromosomes (BACs), six SUT genes were identified characterized S. spontaenum. Phylogenetic analyses revealed that two pairs SsSUTs (SsSUT1/SsSUT3 SsSUT5/SsSUT6) could clustered together into separate monocot specific groups, while SsSUT2 SsSUT4 separated with members from dicot species. Gene structure comparison demonstrated number position exons/introns SUTs highly conserved among close orthologs; contrast, there variations paralogous Sacchuarm. Though high polyploidy level, gene allelic haplotype analysis showed examined four SsSUT exhibited conservations structures amino acid sequences haplotypes accompanied by intron sizes. expression tissues seedlings under drought stress mature plants three Saccharum species (S.officinarnum, S.spotaneum S.robustum). Both SUT1 SUT4 expressed abundantly at different conditions. SUT2 had similar level all tissues, but SUT3 was undetectable. SUT5 SUT6 lower than member, stronger leaves likely play roles loading. In seeding plant leave water stress, SUT1, SUT2, detectable. these detectable genes, down regulated, while, regulated. this study, we presented first comprehensive a whole family, Saccharum. We speculated spotaneum genome. Out members, SsSUTs, SsSUT5 SsSUT6 recent duplication rapid evolution, ancient families. Despite polypoidy genome, functional redundancy may not exist supported evidence strong purifying selection allele. low active member family because undetectable our might pseudogene harbored integrated structure. main transporter, sub-functional divergence response accumulation development