Regulation of MYB Transcription Factors of Anthocyanin Synthesis in Lily Flowers

Abstract

Flower color is the decisive factor that affects the commercial value of ornamental flowers. Therefore, it is important to study the regulation of flower color formation in lily to discover the positive and negative factors that regulate this important trait. In this study, MYB transcription factors (TFs) were characterized to understand the regulatory mechanism of anthocyanin biosynthesis in lily. Two R2R3-MYB TFs, LvMYB5, and LvMYB1, were found to regulate anthocyanin biosynthesis in lily flowers. LvMYB5, which has an activation motif, belongs to the SG6 MYB protein subgroup of Arabidopsis thaliana. Transient expression of LvMYB5 indicated that LvMYB5 can promote coloration in Nicotiana benthamiana leaves, and that expression of LvMYB5 increases the expression levels of NbCHS, NbDFR, and NbANS. VIGS experiments in lily petals showed that the accumulation of anthocyanins was reduced when LvMYB5 was silenced. Luciferase assays showed that LvMYB5 can promote anthocyanin synthesis by activating the ANS gene promoter. Therefore, LvMYB5 plays an important role in flower coloration in lily. In addition, the transient expression experiment provided preliminary evidence that LvMYB1 (an R2R3-MYB TF) inhibits anthocyanin synthesis in lily flowers. The discovery of activating and inhibitory factors related to anthocyanin biosynthesis in lily provides a theoretical basis for improving flower color through genetic engineering. The results of our study provide a new direction for the further study of the mechanisms of flower color formation in lilies.

Integrative analysis of transcriptome and metabolome reveals flavonoid biosynthesis regulation in Rhododendron pulchrum petals

“…In addition, flavonoid biosynthesis is also jointly controlled by a variety of transcription factors, including MYB, bHLH, TTG1 (WD40 repeat protein), TTG2 (WRKY44), TT16/AGL32 (MADS protein) and TT1 [15]. In recent years, genes and transcription factors involved in anthocyanin biosynthesis have been identified in many plants [16][17][18][19][20].…”

AcMYB1 Interacts With AcbHLH1 to Regulate Anthocyanin Biosynthesis in Aglaonema commutatum

“…Many R2R3-MYBs involved in the regulation of anthocyanin biosynthesis have been identified at the genetic and molecular levels (Nuraini et al, 2020 ; Yin et al, 2021 ), such as PeMYB2, PeMYB11, and PeMYB12 in Phalaenopsis spp. (Hsu et al, 2015 ); MaAN2 and MaMYBA in Muscari armeniacum (Chen et al, 2017 , 2019 ); MdMYB10 and MdMYB6 in Malus × domestica (Espley et al, 2009 ; Xu et al, 2020 ); and FhPAP1 from Freesia hybrida (Li et al, 2020 ).…”

Anthocyanin Biosynthesis Induced by MYB Transcription Factors in Plants

“…LrMYB15 was involved in the positive regulation of anthocyanins in lily by stimulating transcription of anthocyanin biosynthesis genes [ 61 ]. LvMYB5-silencing in VIGS experiments significantly reduced anthocyanins accumulation in lily petals [ 62 ]. AaMYB2 positively related to anthocyanin biosynthesis in Anthurium spathes [ 63 ].…”