Ca2+ Mediates the Self-Assembly of the Foot Proteins of Pinctada fucata from the Nanoscale to the Microscale
Ca2+ Mediates the Self-Assembly of the Foot Proteins of Pinctada fucata from the Nanoscale to the Microscale
复制标题
Ca2介导珠母贝足蛋白从纳米尺度到微米尺度的自组装
DOI：
10.1021/acs.biomac.6b01125
复制
发表时间：
2016
影响因子：
6.2
通讯作者：
Zhang Rongqing
中科院分区：
文献类型：
--
作者：
Liu Chuang;Xie Liping;Zhang Rongqing
双壳类动物，如贻贝和珍珠牡蛎，从足部分泌蛋白质足丝，使其附着在海水下的固体表面。虽然贻贝足丝的生物分子已被广泛研究，但它们如何从可溶性蛋白质前体形成水下不溶性丝，以及它们如何从生物分子产生分级微尺度丝仍不清楚。在这里，使用珍珠牡蛎Pinctada fucataas模型，金属离子，而不是pH值被发现在足丝的固化过程中发挥关键作用。特别地，Ca 2+可以诱导足蛋白和深渊蛋白的自组装，导致聚集体形成。在10 mM的浓度下，形成直径约26 μm，长度范围为50 - 400 μm的蛋白质纤维。此外，纤维由60-90 nm的纳米球组成，使人联想到线的超微结构尺寸。Ca ~（2+）可以通过磷酸化丝氨酸和/或血管性血友病因子A型结构域与血小板反应蛋白-1等深海蛋白相互作用。这项研究提供了深入了解如何形成足丝从可溶性蛋白质分子到不溶性线程水下，并可能激发进一步的生物材料设计用于水下使用。
Bivalve animals such as mussels and pearl oysters secrete proteinaceous byssus from the foot to attach themselves to solid surfaces under seawater. Although the biomolecules of mussel byssus have been extensively studied, how they form insoluble threads underwater from soluble protein precursors and how they produce hierarchical microscale threads from biomolecules remains unclear. Here, using the pearl oysterPinctada fucataas a model, metal ions rather than pH are found to play critical roles in the solidification process of the byssus. Particularly, Ca2+can induce self-assembly of the foot proteins and the byssal proteins, resulting in aggregate formation. At a concentration of 10 mM, protein fibers with a diameter of approximately 26 μm and a length ranging from 50 to 400 μm were formed. Moreover, the fibers are composed of 60–90 nm nanospheres, reminiscent of the ultrastructure sizes of threads. It is proposed that Ca2+can interact with byssal proteins such as thrombospondin-1 containing protein through phosphorylated serine and/or von Willebrand factor type A domains. This study provides insight into how the byssus forms from the soluble protein molecules into insoluble threads underwater and may inspire further biomaterial design for underwater use.