1
|
Lap B, Rai M, Tyagi W. Playing with colours: genetics and regulatory mechanisms for anthocyanin pathway in cereals. Biotechnol Genet Eng Rev 2021; 37:1-29. [PMID: 34470563 DOI: 10.1080/02648725.2021.1928991] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Cereals form the most important source of energy in our food. Currently, demand for coloured food grains is significantly increasing globally because of their antioxidant properties and enhanced nutritional value. Coloured grains of major and minor cereals are due to accumulation of secondary metabolites like carotenoids and flavonoids such as anthocyanin, proanthocyanin, phlobaphenes in pericarp, aleurone, lemma, testa or seed coat of grains. Differential accumulation of colour in grains is regulated by several regulatory proteins and enzymes involved in flavonoid and caroteniod biosynthesis. MYB and bHLH gene family members are the major regulators of these pathways. Genes for colour across various cereals have been extensively studied; however, only a few functional and allele-specific markers to be utilized directly in breeding programmes are reported so far. In this review, while briefly discussing the well studied and explored carotenoid pathway, we focus on a much more complex anthocyanin pathway that is found across cereals. The genes and their orthologs that are responsible for encoding key regulators of anthocyanin biosynthesis are discussed. This review also focuses on the genetic factors that influence colour change in different cereal crops, and the available/reported markers that can be used in breeding programs for utilizing this pathway for enhancing food and nutritional security.
Collapse
Affiliation(s)
- Bharati Lap
- School of Crop Improvement, CPGS-AS, CAU (I), Umiam, India
| | - Mayank Rai
- School of Crop Improvement, College of Post Graduate Studies in Agricultural Sciences, Central Agricultural University (Imphal) College of Post-Graduate Studies, Umiam, Meghalaya, India
| | - Wricha Tyagi
- New Zealand Institute for Plant and Food Research Ltd, Umiam, India
| |
Collapse
|
3
|
Jia Y, Selva C, Zhang Y, Li B, McFawn LA, Broughton S, Zhang X, Westcott S, Wang P, Tan C, Angessa T, Xu Y, Whitford R, Li C. Uncovering the evolutionary origin of blue anthocyanins in cereal grains. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2020; 101:1057-1074. [PMID: 31571294 DOI: 10.1111/tpj.14557] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 09/16/2019] [Accepted: 09/24/2019] [Indexed: 05/23/2023]
Abstract
Functional divergence after gene duplication plays a central role in plant evolution. Among cereals, only Hordeum vulgare (barley), Triticum aestivum (wheat) and Secale cereale (rye) accumulate delphinidin-derived (blue) anthocyanins in the aleurone layer of grains, whereas Oryza sativa (rice), Zea mays (maize) and Sorghum bicolor (sorghum) do not. The underlying genetic basis for this natural occurrence remains elusive. Here, we mapped the barley Blx1 locus involved in blue aleurone to an approximately 1.13 Mb genetic interval on chromosome 4HL, thus identifying a trigenic cluster named MbHF35 (containing HvMYB4H, HvMYC4H and HvF35H). Sequence and expression data supported the role of these genes in conferring blue-coloured (blue aleurone) grains. Synteny analyses across monocot species showed that MbHF35 has only evolved within distinct Triticeae lineages, as a result of dispersed gene duplication. Phylogeny analyses revealed a shared evolution pattern for MbHF35 in Triticeae, suggesting that these genes have co-evolved together. We also identified a Pooideae-specific flavonoid 3',5'-hydroxylase (F3'5'H) lineage, termed here Mo_F35H2, which has a higher amino acid similarity with eudicot F3'5'Hs, demonstrating a scenario of convergent evolution. Indeed, selection tests identified 13 amino acid residues in Mo_F35H2 that underwent positive selection, possibly driven by protein thermostablility selection. Furthermore, through the interrogation of barley germplasm there is evidence that HvMYB4H and HvMYC4H have undergone human selection. Collectively, our study favours blue aleurone as a recently evolved trait resulting from environmental adaptation. Our findings provide an evolutionary explanation for the absence of blue anthocyanins in other cereals and highlight the importance of gene functional divergence for plant diversity and environmental adaptation.
Collapse
Affiliation(s)
- Yong Jia
- Western Barley Genetic Alliance, Murdoch University, Murdoch, WA, 6150, Australia
- State Agricultural Biotechnology Centre (SABC), School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, 6150, Australia
| | - Caterina Selva
- School of Agriculture, Food and Wine, Adelaide University, Adelaide, SA, 5064, Australia
| | - Yujuan Zhang
- State Agricultural Biotechnology Centre (SABC), School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, 6150, Australia
| | - Bo Li
- Hubei Collaborative Innovation Centre for Grain Industry, Yangtze University, Jingzhou, Hubei, 434025, China
| | - Lee A McFawn
- Western Barley Genetic Alliance, Murdoch University, Murdoch, WA, 6150, Australia
- Department of Primary Industry and Regional Development, Government of Western Australia, South Perth, WA, 6155, Australia
| | - Sue Broughton
- Western Barley Genetic Alliance, Murdoch University, Murdoch, WA, 6150, Australia
- Department of Primary Industry and Regional Development, Government of Western Australia, South Perth, WA, 6155, Australia
| | - Xiaoqi Zhang
- Western Barley Genetic Alliance, Murdoch University, Murdoch, WA, 6150, Australia
- State Agricultural Biotechnology Centre (SABC), School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, 6150, Australia
| | - Sharon Westcott
- Western Barley Genetic Alliance, Murdoch University, Murdoch, WA, 6150, Australia
- Department of Primary Industry and Regional Development, Government of Western Australia, South Perth, WA, 6155, Australia
| | - Penghao Wang
- State Agricultural Biotechnology Centre (SABC), School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, 6150, Australia
| | - Cong Tan
- Western Barley Genetic Alliance, Murdoch University, Murdoch, WA, 6150, Australia
- State Agricultural Biotechnology Centre (SABC), School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, 6150, Australia
| | - Tefera Angessa
- Western Barley Genetic Alliance, Murdoch University, Murdoch, WA, 6150, Australia
- Department of Primary Industry and Regional Development, Government of Western Australia, South Perth, WA, 6155, Australia
| | - Yanhao Xu
- Hubei Collaborative Innovation Centre for Grain Industry, Yangtze University, Jingzhou, Hubei, 434025, China
| | - Ryan Whitford
- School of Agriculture, Food and Wine, Adelaide University, Adelaide, SA, 5064, Australia
| | - Chengdao Li
- Western Barley Genetic Alliance, Murdoch University, Murdoch, WA, 6150, Australia
- State Agricultural Biotechnology Centre (SABC), School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA, 6150, Australia
- Department of Primary Industry and Regional Development, Government of Western Australia, South Perth, WA, 6155, Australia
| |
Collapse
|