The Formation of Anthocyanic Vacuolar Inclusions in Arabidopsis thaliana and Implications for the Sequestration of Anthocyanin Pigments

• Published in: Molecular plant Vol. 3; no. 1; pp. 78 - 90
• Main Authors: Pourcel, Lucille, Irani, Niloufer G., Lu, Yuhua, Riedl, Ken, Schwartz, Steve, Grotewold, Erich
• Format: Journal Article
• Language: Chinese; English
• Published: England Elsevier Inc 01.01.2010; Oxford University Press
• Subjects: Anthocyanin; Anthocyanins - metabolism; Arabidopsis - drug effects; Arabidopsis - genetics; Arabidopsis - metabolism; autophagy; Autophagy - drug effects; AVI文件; Chromatography, High Pressure Liquid; cyanidin 3-glucoside; Glucosides - metabolism; Microscopy; Plants, Genetically Modified - drug effects; Plants, Genetically Modified - genetics; Plants, Genetically Modified - metabolism; Tandem Mass Spectrometry; vacuolar inclusion; Vacuoles - metabolism; vanadate; Vanadates - pharmacology; 叶表皮细胞; 拟南芥; 泡包; 自噬作用; 色素积累; 花色苷; 花青素; Anthocyanin; vacuolar inclusion; autophagy; cyanidin 3-glucoside; vanadate
• ISSN: 1674-2052; 1752-9867
• DOI: 10.1093/mp/ssp071

Anthocyanins are flavonoid pigments that accumulate in the large central vacuole of most plants. Inside the vacuole, anthocyanins can be found uniformly distributed or as part of sub-vacuolar pigment bodies, the Anthocyanic Vacuolar Inclusions (AVIs). Using Arabidopsis seedlings grown under anthocyanin-inductive conditions as a model to understand how AVIs are formed, we show here that the accumulation of AVIs strongly correlates with the formation of cyanidin 3-glucoside (C3G) and derivatives. Arabidopsis mutants that fail to glycosylate anthocyanidins at the 5-O position (5gt mutant) accumulate AVIs in almost every epidermal cell of the cotyledons, as compared to wild-type seedlings, where only a small fraction of the cells show AVIs. A similar phenomenon is observed when seedlings are treated with vanadate. Highlighting a role for autophagy in the formation of the AVIs, we show that various mutants that interfere with the autophagic process (atg mutants) display lower numbers of AVIs, in addition to a reduced accumulation of anthocyanins. Interestingly, vanadate increases the numbers of AVIs in the atg mutants, suggesting that several pathways might participate in AVI formation. Taken together, our results suggest novel mechanisms for the formation of sub-vacuolar compartments capable of accumulating anthocyanin pigments.