Department of Medicine, Division of Nephrology and Hypertension, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.
Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.
J Cell Sci. 2018 Apr 9;131(7):jcs203950. doi: 10.1242/jcs.203950.
The cellular microenvironment, characterized by an extracellular matrix (ECM), played an essential role in the transition from unicellularity to multicellularity in animals (metazoans), and in the subsequent evolution of diverse animal tissues and organs. A major ECM component are members of the collagen superfamily -comprising 28 types in vertebrates - that exist in diverse supramolecular assemblies ranging from networks to fibrils. Each assembly is characterized by a hallmark feature, a protein structure called a triple helix. A current gap in knowledge is understanding the mechanisms of how the triple helix encodes and utilizes information in building scaffolds on the outside of cells. Type IV collagen, recently revealed as the evolutionarily most ancient member of the collagen superfamily, serves as an archetype for a fresh view of fundamental structural features of a triple helix that underlie the diversity of biological activities of collagens. In this Opinion, we argue that the triple helix is a protein structure of fundamental importance in building the extracellular matrix, which enabled animal multicellularity and tissue evolution.
细胞微环境以细胞外基质 (ECM) 为特征，在动物（后生动物）从单细胞向多细胞的转变中发挥了重要作用，并在随后的各种动物组织和器官的进化中发挥了重要作用。细胞外基质的主要成分之一是胶原蛋白超家族的成员——脊椎动物中有 28 种——它们存在于从网络到原纤维的各种超分子组装体中。每种组装体都有一个标志性特征，即一种称为三螺旋的蛋白质结构。目前知识上的一个空白是理解三螺旋如何在构建细胞外支架时对信息进行编码和利用的机制。最近被揭示为胶原蛋白超家族中进化上最古老成员的 IV 型胶原蛋白，为三螺旋的基本结构特征提供了一个新的视角，这些特征是胶原蛋白多样性的生物学活性的基础。在本观点中，我们认为三螺旋是构建细胞外基质的重要蛋白质结构，它使动物多细胞性和组织进化成为可能。
