Abstract:

A cDNA encoding MdGAMYB was cloned from the terminal buds of‘Nagafu 2’apple. We further performed related research and analysis on its bioinformatics and expression patterns. Sequences analysis indicated that the opening reading frame of MdGAMYB was 1 656 bp and it encoded 551 amino acids. The molecular weight of MdGAMYB protein is 59.741 kD. Bioinformation showed that MdGAMYB protein had many glycosylation and phosphorylation sites. Amino acid sequence alignment showed that MdGAMYB was similar to other GAMYB proteins. They all shared a R2R3 DNA binding domain and typical conserved domains including Box1，Box2 and Box3. Phylogenetic analysis indicated that MdGAMYB protein was highly homologous to other GAMYB proteins，such as pear，plum，jujube，strawberry and grape. Real time PCR analysis showed that MdGAMYB was highly expressed in leaves，buds and flowers，exhibiting a tissue-specific expressed. Additionally，results showed that the MdGAMYB transcripts，flower induction and flowering rates were all inhibited by exogenous GA3 treatment. We found that the expression of MdGAMYB was higher in‘Yanfu 6’than‘Nagafu 2’during flower induction.

Key words: apple, MdGAMYB, gene clone, gene expression, flower induction