The groups of plant flavonoid metabolites termed anthocyanins and proanthocyanins (PA) are responsible for pigmentation in seeds, flowers and fruits. Anthocyanins and PAs are produced by a pathway of enzymes which are transcriptionally regulated by transcription factors (TFs) that form the MYB-bHLH-WD40 (MBW) complex. In this study, transcriptomic analysis of purple-pigmented kiwifruit skin and flesh tissues identified MYBC1, from subgroup 5 of the R2R3 MYB family, and WRKY44 (highly similar to Arabidopsis TTG2) as candidate activators of the anthocyanin pathway. Transient over-expression of MYBC1 and WRKY44 induced anthocyanin accumulation in tobacco leaves. Dual luciferase promoter activation assays revealed that both MYBC1 and WRKY44 were able to strongly activate the promoters of the kiwifruit F3′H and F3′5′H genes. These enzymes are branch points of the pathway which specifies the type of anthocyanin accumulated. Stable over-expression of MYBC1 and WRKY44 in kiwifruit calli activated the expression of F3′5′H and PA-related biosynthetic genes as well as increasing levels of PAs. These results suggest that while previously characterised anthocyanin activator MYBs regulate the overall anthocyanin biosynthesis pathway, the PA-related TFs, MYBC1 and WRKY44, more specifically regulate key branch points. This adds a layer of regulatory control that potentially balances anthocyanin and PA levels. Anthocyanins are a group within the flavonoid family of plant secondary metabolites that determine the colour of flowers and plant organs, as well as indicator for ripeness and quality in fruit 1,2. Flavonoids derive from phenylalanine via the general phenylpropanoid pathway which leads to different pathway branches responsible for lignins, stilbenes, condensed tannins (proanthocyanin) and anthocyanins 3. Anthocyanin is produced by the biosynthetic pathway consisting of the commonly termed early biosynthetic enzymes, chalcone synthase (CHS), chalcone isomerase (CHI), flavanone 3-hydroxylase (F3H), flavonoid 3′-hydroxylase (F3′H), flavonoid 3′,5′-hydroxylase (F3′5′H) and the late biosynthetic enzymes dihydroflavonol 4-reductase (DFR), leucoanthocyanidin dioxygenase (LDOX), and flavonoid-3-glucosyltransferase (F3GT) 2. Within the flavonoid family, proanthocyanins (PAs), also known as condensed tannins, are oligomers of epicatechins and catechins that are usually accumulated in the seed coats of many plants, and are well studied in the model plants Medicago truncatala and Arabidopsis 4,5. The enzyme flavonol synthase (FLS) converts dihydroflavonol from the anthocyanin pathway into flavonols. The downstream enzymes leucoanthocyanidin reductase (LAR) and anthocyanidin reductase (ANR) are responsible for the conversion of anthocyanidin to catechin and epicatechin 6,7. Parts of the anthocyanin and PA pathways overlap, as enzymes in the respective pathways utilise and potentially compete for the same intermediate substrates. The pathway direction is determined at the F3′H and F3′5′H branch points, two enzymes which hydroxylate the ...