Amyloids are protein aggregates with a highly ordered spatial structure giving them unique physicochemical properties. Different amyloids not only participate in the development of numerous incurable diseases but control vital functions in archaea, bacteria and eukarya. Plants are a poorly studied systematic group in the field of amyloid biology. Amyloid properties have not yet been demonstrated for plant proteins under native conditions in vivo. Here we show that seeds of garden pea Pisum sativum L. contain amyloid-like aggregates of storage proteins, the most abundant one, 7S globulin Vicilin, forms bona fide amyloids in vivo and in vitro. Full-length Vicilin contains 2 evolutionary conserved β-barrel domains, Cupin-1.1 and Cupin-1.2, that self-assemble in vitro into amyloid fibrils with similar physicochemical properties. However, Cupin-1.2 fibrils unlike Cupin-1.1 can seed Vicilin fibrillation. In vivo, Vicilin forms amyloids in the cotyledon cells that bind amyloid-specific dyes and possess resistance to detergents and proteases. The Vicilin amyloid accumulation increases during seed maturation and wanes at germination. Amyloids of Vicilin resist digestion by gastrointestinal enzymes, persist in canned peas, and exhibit toxicity for yeast and mammalian cells. Our finding for the first time reveals involvement of amyloid formation in the accumulation of storage proteins in plant seeds.

淀粉样蛋白是具有高度有序的空间结构的蛋白质聚集体，赋予它们独特的物理化学特性。不同的淀粉样蛋白不仅参与许多不治之症的发展，而且还控制古细菌，细菌和真核生物的重要功能。在淀粉样生物领域，植物是一个研究不足的系统群体。在体内天然条件下尚未证明植物蛋白的淀粉样蛋白特性。在这里，我们显示豌豆Pisum sativum的种子L.含有淀粉样蛋白样的存储蛋白聚集体，最丰富的是7S球蛋白Vicilin，可在体内和体外形成真正的淀粉样蛋白。全长Vicilin包含2个进化保守的β-桶结构域Cupin-1.1和Cupin-1.2，它们在体外自组装成具有相似理化特性的淀粉样原纤维。但是，不同于Cupin-1.1的Cupin-1.2原纤维可以使Vicilin发生纤颤。在体内，Vicilin在子叶细胞中形成淀粉样蛋白，该淀粉样蛋白结合淀粉样蛋白特异性染料并具有对去污剂和蛋白酶的抗性。Vicilin淀粉样蛋白积累在种子成熟过程中增加，并在发芽时减弱。Vicilin的淀粉样蛋白可抵抗胃肠道酶的消化，在豌豆罐头中持续存在，并对酵母和哺乳动物细胞具有毒性。