Isolation And Expression Analysis Of MYB Transcription Factors Relate To Anthocyanins Accumulation In Kiwifruit

As the beautiful colour and unique flavor, sweet and refreshing taste, especially nutrient-rich, thered-fleshed kiwifruit becomes very popular.‘Hongyang’(Actinidia chinesis cv ‘Hongyang’) which isthe most representative red-fleshed kiwifruit cultivar has a red color fruit core to attract people. In orderto find out the mechanism on anthocyanins accumulation difference between red-fleshed kiwifruit‘Hongyang’ and green-fleshed kiwifruit ‘White’（Actinidia eriantha Benth）, we analyzed the content ofanthocyanins and the expression patterns of MYB transcription factor gene during fruit development.The main results are listed as follows:The anthocyanins content in ‘Hongyang’ and ‘White’ kiwifruit during fruit development weretexted by high performance liquid chromatography (HPLC). The results showed that the anthocyaninscontent of ‘Hongyang’ kiwifruit was increasing as fruit development, while anthocyanins remained arelatively low levels in ‘White’ kiwifruits. In the same fruit development period, anthocyaninsproduction of ‘Hongyang’ was significantly higher than that of ‘White’, especially nearly44timeshigher during the mature stage.HYAcMYB and WtAeMYB gene were isolated from ‘Hongyang’ and ‘White’ kiwifruit by reversetranscription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE).Sequences analysis indicated that HYAcMYB sequence was67bp longer than WtAeMYB in the3’UTR.The expression pattern of HYAcMYB and WtAeMYB during fruit development period were analyzed byreal-time PCR. The results showed that the expression pattern of HYAcMYB was consistent to theanthocyanins content in ‘Hongyang’ kiwifruits. The AcMYB expression level of ‘Hongyang’ wassignificantly higher than ‘White’ in the same fruit development period. Especially, the expression levelof HYAcMYB reached9times higher than that of WtAeMYB in kiwifruits65days after full bloom. All ofthese indicated that AcMYB may involve an important role in the anthocyanins production, and futherstudies are needed to elucidate the detail function and the relationship with other structural genesinvolved anthocyanin biosynthesis.