Prickle morphogenesis in rose is coupled with secondary metabolite accumulation and governed by canonical MBW transcriptional complex.

Prickles, the vasculature less epidermal outgrowths resembling trichomes, are defense organs protecting plants against herbivory. Despite biological significance, the mechanism of prickle morphogenesis remains obscure. Here, we show that like trichomes, prickles accumulate secondary metabolites, especially lignin and flavonoids, during morphogenesis. Cognate transcriptome analysis demonstrated that upregulation of a hormone-regulated transcriptional activation-inhibition network, known to govern trichome morphogenesis, likely triggers the differentiation of epidermal cells to outgrow into prickle.