In silico and expression analysis of the tonoplast monosaccharide transporter (TAT) gene family in Pyrus bretschneideri

摘要

In this study, we reported the identification, structural characteristics, phylogenetic, and expression patterns of 6 TMT genes (PbTMT1 to PbTMT6) in Pyrus bretschneideri. The 6 PbTMT genes were located on chromosomes 6, 5, 5, 10, 15, and 15, respectively. Analysis of the exons/introns revealed that all 6 genes contain the same exons and display a high degree of conservation with corresponding TMT genes in other plant species. Comparative screening of the motifs in PbTMT proteins indicated high conservation in terms of number, width, and order of motifs, which indirectly indicated that the 6 PbTMT proteins are indeed members of the TMT gene family. Phylogenetic analysis revealed that PbTMTs exhibited the greatest homology with those of Malus domestica. Analysis of expression levels of the 6 PbTMT genes revealed that transcripts of PbTMT5 were nearly undetectable in seeds but were highly expressed in stems and flowers. The other PbTMTs were differentially expressed in all tissues. PbTMT1 exhibited relatively uniform expression in various tissues, whereas PbTMT2, PbTMT3 and PbTMT6 were highly expressed in mature leaves. PbTMT4 was highly expressed in mature fruits, possibly indicating a key role in fruit sugar accumulation. These results would be useful in the selection of important candidate PbTMTs.