Genetics and Biochemistry of Zero-Tannin Lentils

Abstract

The zero-tannin trait in lentil is controlled by a single recessive gene (tan) that results in a phenotype characterized by green stems, white flowers, and thin, transparent, or translucent seed coats. Genes that result in zero-tannin characteristics are useful for studies of seed coat pigmentation and biochemical characters because they have altered pigmentation. In this study, one of the major groups of plant pigments, phenolic compounds, was compared among zero-tannin and normal phenotypes and genotypes of lentil. Biochemical data were obtained by liquid chromatography-mass spectrometry (LC-MS). Genomic sequencing was used to identify a candidate gene for the tan locus. Phenolic compound profiling revealed that myricetin, dihydromyricetin, flavan-3-ols, and proanthocyanidins are only detected in normal lentil phenotypes and not in zero-tannin types. The molecular analysis showed that the tan gene encodes a bHLH transcription factor, homologous to the A gene in pea. The results of this study suggest that tan as a bHLH transcription factor interacts with the regulatory genes in the biochemical pathway of phenolic compounds starting from flavonoid-3’,5’-hydroxylase (F3’5’H) and dihydroflavonol reductase (DFR).

Development and validation of a robust KASP marker for zt2 locus in faba bean (Vicia faba)

“…Among the potential candidate genes, WD40 repeat proteins are known to be part of a complex system of transcription factors which are involved in the regulation of genes involved in the synthesis of anthocyanins in different plant species including legumes (e.g. Hellens et al, ; Khazaei et al, ; Li et al, ; Mirali et al, ). Webb et al () showed that the ZT1 gene in faba bean is an ortholog of the M. truncatula WD‐40 transcription factors Transparent Testa Glabra 1 (TTG1).…”

Polyphenolic Profile of Seed Components of White and Purple Flower Pea Lines

“…The phenolic compounds and the six isotopically labeled internal standards used in this study are listed in Table 2, along with their supplier information. Different classes of the phenolic compounds including subclasses of phenolic acids, stilbenes, anthocyanidins, flavan-3-ols, proanthocyanidins, flavanones, flavones, dihydroflavonols, and flavonols analyzed in this study were previously quantified in lentils (Mirali et al, 2016(Mirali et al, , 2017. Catechin-13 C 3 , 4-hydroxybenzoic acid-13 C 7 , ferulic acid-d 3 , resveratrol (4-hydroxyphenyl-13 C 6 ), vanillin ring-13 C 6 , and quercetin-d 3 were used as internal standards.…”

“…(Weidenbörner et al, 1990). Mirali et al (2016Mirali et al ( , 2017 reported the presence of flavan-3-ols and proanthocyanidins in brown, green, and gray lentil (Lens culinaris Medik.) seed coats, and their absence in zero-tannin types.…”

A bHLH transcription factor (VfTT8) underlieszt2, the locus determining zero tannin content in faba bean (Vicia faba L.)

“…In pea, the absence of pigmentation in the flower is the result of mutations in loci A and A2 encoding a bHLH transcription factor and a WD40 protein, respectively 21 . In lentils the zero-tannin trait is controlled by a single recessive gene (tan) that encodes a bHLH transcription factor, homologous to the A gene in pea 22 . In faba bean, the zero-tannin (zt) trait is a simple character, governed independently by two complementary recessive genes zt1 and zt2 2,23 .…”

“…A pooled sample comprising all samples considered in the experiment was included for each gene as inter-run calibrator to detect and correct inter-run variation. No-template controls were also included.Specific primer pairs were designed using the following criteria: Tm of 60 ± 1˚C and PCR amplicon lengths of 80-120 bp, yielding primer sequences with lengths of[19][20][21][22][23][24][25][26] nucleotides and GC contents of 40-80%. Designed primers were synthesized by Integrated DNA Technologies (Leuven, Belgium).…”