Abstract:

In order to study the function of 3-O-glucosyltransferase gene(3GT) in blueberry and to explore the roles of 3-O-glucosyltransferase in anthocyanin synthesis, a single copy of 3GT was cloned from the cDNA of blueberry fruit by RT-PCR, which was 1 371 bp and encoded 456 amino acids. 3GT was located at the end of chromosome Ⅳ in blueberry and contains 3 exons and 2 introns. The molecular formula of the protein was C₂₂₇₉H₃₅₂₁N₅₉₅O₆₅₀S₁₅, and the theoretical isoelectric point (pI) was 6.14. Information analysis predicted that 3GT was one hydrophilic protein and unstable protein with 37 phosphorylation sites, without signal peptide,or transmembrane domain. The secondary structure of protein consists of α-helix (Hh), extended chain (Ee), β-angle (Tt) and random curl (Cc), among which α-helix accounted for 40%.As one number of GTB-type glycosyltransferase family, the 44th position in the PSPG domain of 3GT was histidine, and the glycosylase donor might be UDP-galactosewas. 3GT was closely related to Kiwifruit, with the homology of amino acids reached 67%. Auto-Dock showed that 3GT had four interaction forces with zymolyte of cyanidin. There were multiple cis-regulatory elements that might relate to light response,stress resistance response and specific hormone response in the promoter of 3GT. The blueberry 3GT gene was cloned.The bioinformatics analysis and function prediction were carried out through online website and prediction software to study the characteristics and function of 3GT.

Key words: Blueberry, 3GT, Gene characterization analysis, Anthocyanin biosynthesis