Abstract: ANK（ankyrin repeat）containing proteins comprise a large protein family，which play important roles in plant growth， development，and signal transduction，no ANK genes have been reported in apple. In this study，MdANK gene family，gene classification，chromosome location，sequence alignment，conserved structure domains and expression profiles of MdANKs were predicted and analyzed with bioinformatics methods，alignment of amino acid sequences and phylogenetic analysis. The results showed that MdANK family contained 351 genes，which was further divided into 16 types and the largest group is the ANK-M type contains 143 proteins. Phylogenic analysis revealed that MdANK genes in apple could be divided into 15 subfamilies（from A to O）according to the phylogenetic analysis tree by MEGA 5. A total of 112 MdANK genes were mapped to 17 chromosomes，whereas 22 MdANK genes were not mapped to any particular chromosome. For example，Chr 2 encompasses the largest number of 36 MdANK genes，while the lowest number（Chr 6，7 and 8）contained 6 MdANK genes. MdANK proteins contained from 72 to 2 429 amino acids and the isoelectric point is from 4.30 to 11.13. Expression analysis showed that the expression levels of most MdANK genes were altered during the ripening process and rootstock-scion interactions process. Our data will provide very useful information for cloning and functional analysis of members of this gene family in apple.

Key words: apple, ANK, gene family, bioinformatics