玉米花青素生物合成代谢调控

doi:10.13560/j.cnki.biotech.bull.1985.2024-0075

摘要/Abstract

摘要：

花青素（anthocyanidin）以糖苷形式与葡萄糖或纤维二糖分子结合存在，是一类水溶性天然色素，广泛存在于自然界中的果蔬和花卉中。花青素具有抗氧化、抗炎、抗肿瘤以及抑制病毒生长等生理活性，因此在食品和医药领域具有广阔的应用前景。随着对植物花青素合成途径的深入研究，花青素生物合成途径逐渐清晰，但是花青素调控基因以及机制仍有很大的探索空间。紫玉米是一种富含花青素的作物，其花青素生物合成途径的研究具有重要的实际意义。近年来，研究人员在富含花青素玉米研究中取得了较大进展，但在花青素玉米的精准育种方面有待进一步研究。本文从玉米的花青素生物合成途径、关键酶基因和调控基因等方面进行综述，系统分析了玉米花青素合成途径中各个结构基因以及MYB、bHLH、WD40等调控基因对花青素合成的影响；阐述了MBW三元复合物对花青素的调控；讨论了富含花青素玉米育种中尚未解决的问题及未来研究方向，以期为今后开展花青素玉米遗传改良以及选育高花青素玉米品种提供参考。

关键词: 花青素, 玉米, 生物合成, 代谢调控

Abstract:

Anthocyanidins exist in the form of glycosides bound to glucose or fibre disaccharide molecules, and are a class of water-soluble natural pigments that are widely found in fruits, vegetables and flowers in nature. Anthocyanins have physiological activities such as antioxidant, anti-inflammatory, anti-tumour, and virus growth inhibition, thus they have broad application prospects in the food and pharmaceutical fields. Purple corn is an anthocyanin-rich crop, and the study of its anthocyanin biosynthesis pathway is of high practical significance. With the in-depth study of anthocyanin synthesis pathway in plants, the anthocyanin biosynthesis pathway has been gradually clarified, but the anthocyanin regulatory genes and the mechanism still have a lot of room for exploration. In recent years, researchers have made great progress in the study of anthocyanin-rich maize, but the precision breeding of anthocyanin-rich maize needs further research. In this paper, we reviewed the anthocyanin biosynthesis pathway, key enzyme genes and regulatory genes of maize, systematically analysed the effects of structural genes in the anthocyanin synthesis pathway of maize as well as regulatory genes, such as MYB, bHLH, WD40, etc., and elaborated on the regulation of anthocyanins by the MBW ternary complex. We also discussed the unresolved issues in breeding anthocyanin-rich maize and the future research direction, with a view to providing reference for future research on the genetic improvement of anthocyanins in maize and the selection of maize varieties with high anthocyanin content.

Key words: anthocyanidin, maize, biosynthesis, metabolic regulation

胡锦锦, 李素贞, 马旭辉, 柳小庆, 谢珊珊, 江海洋, 陈茹梅. 玉米花青素生物合成代谢调控[J]. 生物技术通报, 2024, 40(6): 34-44.

HU Jin-jin, LI Su-zhen, MA Xu-hui, LIU Xiao-qing, XIE Shan-shan, JIANG Hai-yang, CHEN Ru-mei. Regulation of Maize Anthocyanin Biosynthesis Metabolism[J]. Biotechnology Bulletin, 2024, 40(6): 34-44.

图/表 5

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基因名Gene name	染色体位置Chromosome position	名称Name	ID	参考文献Reference
c2（ZmCHS)	4	查尔酮合酶Chalcone synthase	Zm00001d052673	[15⇓-17]
chi1（ZmCHI)	1	查尔酮异构酶Chalcone isomerase	Zm00001d034635	[18]
fht1（ZmF3H)	2	黄烷酮3-羟化酶Flavanon -3-hydroxylase	Zm00001d001960	[19]
pr1（ZmF3'H)	5	黄烷酮3'-羟化酶Flavonoid 3'-hydroxylase	Zm00001d017077	[20⇓-22]
A1（ZmDFR)	3	二氢黄酮醇还原酶Dihydroflavonol 4-reductase	Zm00001d044122	[23-24]
A2（ZmANS)	5	花青素合酶Anthocyanidin aynthase	Zm00001d014914	[25-26]
bz1（ZmUFGT)	9	类黄酮3-O葡萄糖基转移酶Flavonoid 3-Oglucosyltransferase	Zm00001d045055	[27-28]

基因名Gene name	染色体位置Chromosome position	名称Name	ID	参考文献Reference
c2（ZmCHS)	4	查尔酮合酶Chalcone synthase	Zm00001d052673	[15⇓-17]
chi1（ZmCHI)	1	查尔酮异构酶Chalcone isomerase	Zm00001d034635	[18]
fht1（ZmF3H)	2	黄烷酮3-羟化酶Flavanon -3-hydroxylase	Zm00001d001960	[19]
pr1（ZmF3'H)	5	黄烷酮3'-羟化酶Flavonoid 3'-hydroxylase	Zm00001d017077	[20⇓-22]
A1（ZmDFR)	3	二氢黄酮醇还原酶Dihydroflavonol 4-reductase	Zm00001d044122	[23-24]
A2（ZmANS)	5	花青素合酶Anthocyanidin aynthase	Zm00001d014914	[25-26]
bz1（ZmUFGT)	9	类黄酮3-O葡萄糖基转移酶Flavonoid 3-Oglucosyltransferase	Zm00001d045055	[27-28]

转录因子 Transcription factor	基因名 Gene name	位置 Chromosome position	调控着色部位 Regulatory staining site	ID	参考文献 Reference
MYB	Colored aleurone1 (C1)	9	种子糊粉层	Zm00001d044975 Zm00001d008695	[39-40]
	Purple plant (pl)	6	花和营养组织	Zm00001d037118	[39]
	Pericarp color 1 (p1)	1	种皮、玉米棒和花丝	Zm00001d028850	[41-42]
	Pericarp color 2 (p2)	1	花药、花丝	Zm00001d028842	[42]
bHLH	Seed colorcomponent at R1 (r1)	10	种子糊粉层	Zm00001d026147	[40,43]
bHLH	Colored plant1 (B1)	2	叶、叶鞘、雄穗、花药	Zm00001d000236	[44]
WD40	Pale aleurone color1（pac1）	5	整株植株	Zm00001eb250750	[45]

转录因子 Transcription factor	基因名 Gene name	位置 Chromosome position	调控着色部位 Regulatory staining site	ID	参考文献 Reference
MYB	Colored aleurone1 (C1)	9	种子糊粉层	Zm00001d044975 Zm00001d008695	[39-40]
	Purple plant (pl)	6	花和营养组织	Zm00001d037118	[39]
	Pericarp color 1 (p1)	1	种皮、玉米棒和花丝	Zm00001d028850	[41-42]
	Pericarp color 2 (p2)	1	花药、花丝	Zm00001d028842	[42]
bHLH	Seed colorcomponent at R1 (r1)	10	种子糊粉层	Zm00001d026147	[40,43]
bHLH	Colored plant1 (B1)	2	叶、叶鞘、雄穗、花药	Zm00001d000236	[44]
WD40	Pale aleurone color1（pac1）	5	整株植株	Zm00001eb250750	[45]