Transcription Factor-Mediated Control of Anthocyanin Biosynthesis in Vegetative Tissues

Abstract

Plants accumulate secondary metabolites to adapt to environmental conditions. These compounds, here exemplified by the purple-colored anthocyanins, are accumulated upon high temperatures, UV-light, drought, and nutrient deficiencies, and may contribute to tolerance to these stresses. Producing compounds is often part of a more broad response of the plant to changes in the environment. Here we investigate how a transcription-factor-mediated program for controlling anthocyanin biosynthesis also has effects on formation of specialized cell structures and changes in the plant root architecture. A systems biology approach was developed in tomato (Solanum lycopersicum) for coordinated induction of biosynthesis of anthocyanins, in a tissue-and development-independent manner. A transcription factor couple from Antirrhinum that is known to control anthocyanin biosynthesis was introduced in tomato under control of a dexamethasone-inducible promoter. By application of dexamethasone, anthocyanin formation was induced within 24 h in vegetative tissues and in undifferentiated cells. Profiles of metabolites and gene expression were analyzed in several tomato tissues. Changes in concentration of anthocyanins and other phenolic compounds were observed in all tested tissues, accompanied by induction of the biosynthetic pathways leading from Glc to anthocyanins. A number of pathways that are not known to be involved in anthocyanin biosynthesis were observed to be regulated. Anthocyanin-producing plants displayed profound physiological and architectural changes, depending on the tissue, including root branching, root epithelial cell morphology, seed germination, and leaf conductance. The inducible anthocyanin-production system reveals a range of phenomena that accompanies anthocyanin biosynthesis in tomato, including adaptions of the plants architecture and physiology.

Metabolic and molecular analysis of nonuniform anthocyanin pigmentation in tomato fruit under high light

“…3a). As reported before, the increase of gene transcripts is often congruously paralleled by respective protein changes 16 , which then lead to large amounts of metabolite production. Anthocyanin biosynthetic genes, including PAL , C4H , 4CL , CHS1 , CHS2 , CHI , F3H , F3′H , F3′5′H , DFR , ANS and UFGT , showed high transcript abundance in wild-type and Pro35S:BrTT8 seedlings under high-light conditions and very weak signals for F3′H , F3′5′H , DFR and UFGT under low-light conditions.…”

“…The biosynthesis of phenylalanine-derived compounds, especially flavonoids, is mainly regulated by MYB proteins, which constitute the largest class of modulators for secondary metabolism 15,16 . A total of 339 and 230 MYB proteins were characterized in Arabidopsis thaliana and rice, respectively 17 .…”

Construction of a high-density interspecific (Lens culinaris x L. odemensis) genetic map based on functional markers for mapping morphological and agronomical traits, and QTLs affecting resistance to Ascochyta in lentil

“…We have found both traits, Scp and flower color ( FC ), in close linkage positioned in LG6 with overlapping support intervals for genomic location in the Lc x Lo -map. The Scp locus was mapped to a 3.3 Mb region of LcChr6 comprising 46 annotated genes including a candidate gene (Lc25388) encoding an MYB transcription factor MIXTA-like related with anthocyanin synthesis regulation and cell fate [80]. Most of the genes included in the FC support interval (25 out of 37) were annotated in a 7.7 Mb region that includes the whole 3.3 Mb region for Scp ; nevertheless, another 10 genes which were included in the support interval are annotated outside of the 7.7 Mb region of the draft lentil genome, including gene Lc26377 corresponding to the flower color QTL peak marker.…”

A Maternally Deposited Endosperm Cuticle Contributes to the Physiological Defects of transparent testa Seeds

“…The table indicates the backgrounds of the mutant and transgenic lines used in the study. of cuticles, influencing their synthesis and function (Dominguez et al, 2009;España et al, 2014;Outchkourov et al, 2018). The unambiguous identification of flavonoids as components of tomato cuticles was facilitated by the fact that the tomato cuticle can be isolated physically.…”