NF-YB1-regulated expression of sucrose transporters in aleurone facilitates sugar loading to rice endosperm

• Published in: Cell research 2016-03, Vol.26 (3), p.384-388
• Main Authors: Bai, Ai-Ning, Lu, Xiao-Duo, Li, Dong-Qi, Liu, Jin-Xin, Liu, Chun-Ming
• Format: Article
• Language: English
• Subjects: 631/449/2675; 631/45/612/822; 631/80/86; Biomedical and Life Sciences; Cell Biology; Endosperm - metabolism; Gene Expression Regulation, Plant; Letter to the Editor; Life Sciences; Membrane Transport Proteins - genetics; Membrane Transport Proteins - metabolism; Oryza - genetics; Oryza - metabolism; Plant Proteins - genetics; Plant Proteins - metabolism; Transcription Factors - metabolism; 水稻; 糊粉层; 胚乳; 葡萄糖; 蔗糖转运蛋白; 负荷; 部分水解; 韧皮部运输
• ISSN: 1001-0602; 1748-7838
• DOI: 10.1038/cr.2015.116

Cereal endosperms, which consist of an outer aleurone layer and an inner starchy endosperm, provide over 70% staple food for human [www.fao.org]. Rice endosperm development occurs in the caryopsis of a grain. During the grain filling stage, sucrose produced in photosynthetic leaves is transported to grains via the phloem [ 1, 2]. It has been proposed that sucrose, upon arrival in the caryopsis through the phloem located at the dorsal vascular bundle, is partially hydrolyzed by cell wall invertases （CINs） into glu- cose and fructose [3, 4]. Since endosperm is symplastically isolated from maternal tissues, it is assumed that these sug- ars are delivered to the endosperm actively through an ap- oplastic pathway by sugar transporters located in aleurone [5, 6]. However, the exact role of aleurone in regulating sugar transport remains unknown.