Integrated transcriptional and metabolomics signature pattern of pigmented wheat to insight the seed pigmentation and other associated features

Abstract

Anthocyanin biosynthesis in plants is complex, especially in a polyploid monocot wheat plant. Using whole-genome sequencing, transcriptomics, and LC-MS/MS, we investigated anthocyanin pigmentation patterns in (black, blue, and purple) colored wheat seeds. According to differential gene expression profiling, 2AS-MYC, 7DL-MYB, and WD40 regulatory genes control purple pericarp coloration, 4DL-MYC, 2AS-MYC, 7DL-MYB, WD40 control blue aleurone coloration, and 4DL-MYC, 7DL-MYB, WD40 controls black aleurone color. We hypothesized that at least one MYC and MYB isoform is sufficient to regulate the anthocyanin synthesis in pericarp or aleurone. Transcriptomics and metabolomics revealed that the purple pericarp trait is associated with acylated anthocyanins compared to blue aleurone. Based upon the reduced expressions of the genes belonging to the 4D, SSR molecular marker mapping, variant calling using genome sequencing, and IGV browser gene structure visualization, it was inferred that the advanced black and blue wheat lines were substitution lines (4E{4D}), with very small recombinations. Pericarp anthocyanin pigmentation is controlled by a mutation in chromosome 2AS of purple wheat, and environmental variations influence pigmented pericarp trait. The expression patterns of anthocyanin structural and other genes varied in different colored wheat, corroborating differences in agronomical metrics. Ovate seed shape trait in black and blue wheat dragged with 4E chromosome.

Keywords: Anthocyanin; Colored wheat; Seed; Stress; Transcription factor; Transcriptomics; Wheat.