Abstract: The purpose of this study was to identify and analyze HXK gene family in grape. Based on the HXK(hexokinase) gene registration sequence of Arabidopsis thaliana and maize, four HXK genes were identified from the whole genome of Vitis vinifera, namd as VvHXK1, VvHXK2, VvHXK3 and VvHXK4. The bioinformatics analysis were performed on these four genes. The results of protein physicochemical properties showed that the number of amino acids encoded by the four genes was between 412 aa and 524 aa, of which VvHXK4 was a basic amino acid, and the other three were acidic amino acids. In addition, subcellular localization analysis indicated that all four VvHXK genes were localized in the cytoplasm. VvHXK4 was mainly localized in chloroplasts, and VvHXK2 might appear in mitochondria and nucleus. Meanwhile, the secondary structure prediction of the proteins found that the proteins encoded by the four VvHXK genes were mainly α-helix. The structural analysis of exons indicated that VvHXK1 contained 10 exons, and others contained 9 exons, showing that the VvHXK genes were relatively conserved; The initiation of cis-acting element analysis indicated that four VvHXK genes contained ABA response elements, MYB binding region and WRKY transcription factors, but no low temperature response component were found in VvHXK4. Phylogenetic tree analysis showed that the homology relationship between VvHXK1 and Arabidopsis AtHXK1 was the closest, indicating that it not only had the functions of regulating growth and development and affecting the growth of roots, but also had the effect of accelerating aging. The homology relationship between VvHXK2 and potato StHXK1 was recent, showing that it could increase the glucose phosphorylation activity in leaf extract or chloroplast. The homology relationship between VvHXK3 and potato StHXKRP1 was the closest, suggesting that VvHXK2 might be able to induce the expression of sugar in leaves. The homology relationship between VvHXK4 and spinach SoHXK1 was recent, which was important for studying the glucose metabolism of grapes. Fluorescence quantitative analysis showed that VvHXK2, VvHXK3 and VvHXK4 had the highest relative expression under the treatment of 20 g/L glucose, which was the most significant for glucose phosphorylation, and low expression under the treatment of fructose and sucrose. This is important for studying the sugar metabolism of grapes.

Key words: Grape, HXK gene family, Bioinformatics analysis, qRT-PCR, Glycometabolism

CLC Number: 

• Q78

• S663.03