Raffinose family oligosaccharides （RFOs） accumulate in seeds during maturation desiccation in many plant species. However, it remains unclear whether RFOs have a role in establishing seed vigor. GALACTINOL SYNTHASE ...Raffinose family oligosaccharides （RFOs） accumulate in seeds during maturation desiccation in many plant species. However, it remains unclear whether RFOs have a role in establishing seed vigor. GALACTINOL SYNTHASE （GOLS）, RAFFINOSE SYNTHASE （RS）, and STACHYOSE SYNTHASE （STS） are the enzymes responsible for RFO biosynthesis in plants. Interestingly, only raffinose is detected in maize seeds, and a unique maize RS gene （ZmRS） was identified. In this study, we found that two independent mutator （Mu）-interrupted zmrs lines, containing no raffinose but hyperaccumulating galactinol, have significantly reduced seed vigor, compared with null segregant controls. Unlike maize, Arabidopsis thaliana seeds contain several RFOs （raffinose, stachyose, and verbascose）. Manipulation of A. thaliana RFO content by overexpressing ZmGOLS2, ZmRS, or AtSTS demonstrated that co-overexpression of ZmGOLS2 and ZmRS, or overexpression of ZmGOLS2 alone, significantly increased the total content of RFOs and enhanced Arabidopsis seed vigor. Surprisingly, while overexpression of ZmRS increased seed raffinose content, its overexpression dramatically decreased seed vigor and reduced the seed amounts of galactinol, stachyose, and verbascose. In contrast, the atrs5 mutant seeds are similar to those of the wild type with regard to seed vigor and RFO content, except for stachyose, which accumulated in atrs5 seeds. Total RFOs, RFO/sucrose ratio, but not absolute individual RFO amounts, positively correlated with A. thaliana seed vigor, to which stachyose and verbascose contribute more than raffinose. Taken together, these re- sults provide new insights into regulatory mechanisms of seed vigor and reveal distinct requirement for RFOs in modulating seed vigor in a monocot and a dicot.展开更多
棉籽糖家族寡糖(Raffinose family oligosaccharides,RFOs)是α-蔗糖的1,6-半乳糖基延伸物,是一种植物非结构性碳水化合物,主要包括棉籽糖、水苏糖、毛蕊花糖,普遍存在于植物界中。其中,在豆科植物、地黄、水苏、草石蚕等植物中较为常见...棉籽糖家族寡糖(Raffinose family oligosaccharides,RFOs)是α-蔗糖的1,6-半乳糖基延伸物,是一种植物非结构性碳水化合物,主要包括棉籽糖、水苏糖、毛蕊花糖,普遍存在于植物界中。其中,在豆科植物、地黄、水苏、草石蚕等植物中较为常见,属于功能性低聚糖。RFOs因具备调节肠道菌群、预防炎症性肠病、保护肝脏、降血糖等活性功能,在功能性食品开发中的应用潜力巨大。本文主要综述RFOs的来源,RFOs提取、分离、纯化相关技术的研究,以及RFOs的功能性,以期为RFOs的开发和利用提供一定的理论参考,使其能够更好地应用于功能性食品当中。展开更多
文摘Raffinose family oligosaccharides （RFOs） accumulate in seeds during maturation desiccation in many plant species. However, it remains unclear whether RFOs have a role in establishing seed vigor. GALACTINOL SYNTHASE （GOLS）, RAFFINOSE SYNTHASE （RS）, and STACHYOSE SYNTHASE （STS） are the enzymes responsible for RFO biosynthesis in plants. Interestingly, only raffinose is detected in maize seeds, and a unique maize RS gene （ZmRS） was identified. In this study, we found that two independent mutator （Mu）-interrupted zmrs lines, containing no raffinose but hyperaccumulating galactinol, have significantly reduced seed vigor, compared with null segregant controls. Unlike maize, Arabidopsis thaliana seeds contain several RFOs （raffinose, stachyose, and verbascose）. Manipulation of A. thaliana RFO content by overexpressing ZmGOLS2, ZmRS, or AtSTS demonstrated that co-overexpression of ZmGOLS2 and ZmRS, or overexpression of ZmGOLS2 alone, significantly increased the total content of RFOs and enhanced Arabidopsis seed vigor. Surprisingly, while overexpression of ZmRS increased seed raffinose content, its overexpression dramatically decreased seed vigor and reduced the seed amounts of galactinol, stachyose, and verbascose. In contrast, the atrs5 mutant seeds are similar to those of the wild type with regard to seed vigor and RFO content, except for stachyose, which accumulated in atrs5 seeds. Total RFOs, RFO/sucrose ratio, but not absolute individual RFO amounts, positively correlated with A. thaliana seed vigor, to which stachyose and verbascose contribute more than raffinose. Taken together, these re- sults provide new insights into regulatory mechanisms of seed vigor and reveal distinct requirement for RFOs in modulating seed vigor in a monocot and a dicot.
文摘棉籽糖家族寡糖(Raffinose family oligosaccharides,RFOs)是α-蔗糖的1,6-半乳糖基延伸物,是一种植物非结构性碳水化合物,主要包括棉籽糖、水苏糖、毛蕊花糖,普遍存在于植物界中。其中,在豆科植物、地黄、水苏、草石蚕等植物中较为常见,属于功能性低聚糖。RFOs因具备调节肠道菌群、预防炎症性肠病、保护肝脏、降血糖等活性功能,在功能性食品开发中的应用潜力巨大。本文主要综述RFOs的来源,RFOs提取、分离、纯化相关技术的研究,以及RFOs的功能性,以期为RFOs的开发和利用提供一定的理论参考,使其能够更好地应用于功能性食品当中。
