摘要
粮食作物是人类主要的能量来源,大部分作物品种的种子是白色或黄色,而小麦、玉米、水稻等物种中有些品种的种子因黄酮类物质花青素的积累表现出红、蓝、黑等颜色.不同于其他作物中天然存在有色种子的品种,蓝粒小麦则是普通小麦与其他物种杂交形成的,染色体来源比较复杂.尽管近几十年间,依赖于MYB-bHLH-WDR复合体的花青素调控机制在玉米、水稻等作物中被发现,但是蓝粒小麦花青素在小麦糊粉层中积累的机制至今并不清楚.本文简要介绍了玉米、水稻、大麦中已发现的花青素合成调控基因以及其可能的调控机制;阐述了小麦蓝粒基因最新的研究成果,包括小麦蓝粒性状有3个公认的基因来源:来源于十倍体长穗偃麦草的蓝粒基因Ba1、来源于一粒小麦的蓝粒基因Ba2以及来源于百萨偃麦草的蓝粒基因BaThb,并描述它们在染色体中的已知定位.本文还对控制蓝粒性状可能的基因数量以及这些基因在染色体上的定位进行了讨论,对蓝粒性状作为分子标记在小麦细胞遗传分析、育种等领域的应用进行了总结和分析,对小麦蓝粒基因的克隆、应用以及种子花青素积累与作物演化和驯化的关系进行了展望.
As a staple food crop,common wheat is a major source of energy for human beings.It accounts for approximately 30%of the food and 20%of the calories consumed by humans worldwide.However,increased production of common wheat is needed to keep pace with the increasing human population and to balance decreases in wheat yield due to drought,global warming,and other environmental stresses.Therefore,the breeding of common wheat to improve stress tolerance,grain yields,and nutrient levels is important to ensure the safety of the global food supply.Grain color is attractive to both humans and other animals,and the coloration serves as a marker for crop breeding.Thus,grain color is an important agricultural trait in common wheat.Most common wheat species produce white or yellow grains,while a small number of varieties produce red,blue,or black grains due to the accumulation of anthocyanins in their endosperm,episperm,or aleurone layer.The same is true for other staple food crops,including maize,rice,and barley.However,unlike those crops,in which the genes that control grain color are present in the genome,all known blue-grained common wheat is formed by crossing common wheat with species that harbor the genes required for anthocyanin biosynthesis.Therefore,hybrid wheat with blue-colored grains has a complex genome and chromosomal origin.This means that the genes that control grain color are absent from or inactive in the common wheat genome,and this in turn makes it difficult to determine the origin of the blue grain trait in common wheat.Thus,although the anthocyanin biosynthesis pathway,which enables the production of colored grains,is conserved and induced by the transcriptional MYB-bHLH-WDR complex in maize and rice,the genes and molecular mechanism responsible for anthocyanin accumulation in hybrid blue-grained common wheat are unclear.Nonetheless,blue grains are a desired trait among wheat breeders because the coloration serves as a marker for breeding;moreover,grains containing a high anthocyanin content have health benefits for humans.Therefore,it is important to understand the cellular and molecular bases for blue-colored grains in common wheat.Here,we briefly review recent advances in our understanding of the genes and the transcriptional complex that control anthocyanin synthesis in maize,rice,and barley grains.We also discuss the origin of the genes that confer blue grains in hybrid common wheat,and we summarize the use of blue grain coloration as a molecular marker in cytogenetic analysis,molecular marker-assisted breeding,and hybrid breeding in common wheat.Finally,we discuss possible strategies for cloning the blue grainproducing genes in common wheat and the application of those genes to common wheat breeding.We also discuss the evolution of grain color and blue seed genes in common wheat and other food crops.
作者
裴嘉伟
马力耕
Jiawei Pei;Ligeng Ma(College of Life Sciences,Capital Normal University,Beijing 100048,China)
出处
《科学通报》
EI
CAS
CSCD
北大核心
2022年第26期3110-3118,共9页
Chinese Science Bulletin
基金
国家重点基础研究发展计划(2017YFD0101001)
北京市教委-市自然基金委联合资助项目(IDHT20170513)资助。
关键词
花青素
蓝粒小麦
蓝粒基因
分子进化
分子标记
anthocyanins
blue-grained wheat
blue gene
molecular evolution
molecular marker
