Abstract:

The transcriptomes of blueberry fruit（Vaccinium corymbosum‘Jersey’）were analyzed by sequencing transcripts combined from fruits of different development stages. Twenty-one R2R3-MYB genes were identified and further analyzed by WebLogo 3，CLC Sequence Viewer 6 and real-time PCR. In total，6.01 Gb transcriptomic data were obtained，from which 60 481 unigenes were assembled. The quality of the data was proven acceptable. Functional annotation analysis showed that 39 612 unigenes had homologs in GO and COG public database though no hits were found for the rest 20 869 unigenes. These unigenes were assigned into 55 and 25 function categories including signal transduction mechanisms，transcription and metabolism etc. by GO and COG terms，respectively. The putative protein sequences of the 21 R2R3-MYB genes contained the conserved domain of R2R3 and the conserved amino residues of2（G）and 4（W）. Phylogenetic analysis showed that the blueberry R2R3-MYB genes could be divided into 11 subclasses. Six genes in S4，S5 and S6 subclass were thought to be involved in regulating the biosynthesis of anthocyanin. RT-PCR results indicated that six genes were expressed in seven stages of fruit development though differently expressed pattern. Six genes may play an important role in pigmentation.

Key words: blueberry, transcriptome sequencing, R2R3-MYB, transcription factor, bioinformatics