Expression ofVvmybA1Gene and Anthocyanin Accumulation in Various Grape Organs

VvmybA1 is known to encode a transcriptional factor that induces the anthocyanin biosynthesis in grape skins. However, no VvmybA1 mRNA was detected in the young leaves of Cabernet Sauvignon, Dornfelder, or Muscat Hamburg or in the tendrils or stem epidermis of Muscat Bailey A, although these organs accumulated some anthocyanin. These results indicate that VvmybA1 in these cultivars was transcribed specifically in the berry skin. VvmybA1 of Bailey Alicant A, a teinturier cultivar, was transcribed in all the organs that accumulate anthocyanin, which shows that the organ specificity of its expression was probably reduced.