Institute of Biological Sciences and Biotechnology, Donghua University, Shanghai 201620, China.
Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
Genes (Basel). 2019 Jun 3;10(6):425. doi: 10.3390/genes10060425.
Spiders often produce multiple types of silk, each with unique properties suiting them to certain tasks and biological functions. Orb-weaver spiders can generate more than six types of silk fibroins, with pyriform silk used to form attachment discs, adhering silk to other surfaces and substances. The unique higher-order structuring of silk fibroins has been cited as the source of their remarkable biomechanical properties. Even so, only one full-length gene sequence of pyriform silk protein 1 (PySp1) from has been reported, and studies on the mechanical properties of natural pyriform silk fibers are also lacking. To better understand the PySp1 family of genes, we used long-distance PCR (LD-PCR) to determine the sequence of PySp1 in the species. This full-length PySp1 gene is 11,931 bp in length, encoding for 3976 amino acids residues in non-repetitive N- and C-terminal domains with a central largely repetitive region made up of sixteen remarkably homogeneous units. This was similar to the previously reported PySp1 sequence, with PySp1 from also having a long repetitive N-linker that bridges the N-terminal and repetitive regions. Predictions of secondary structure and hydrophobicity of PySp1 showed the pyriform silk fiber's functional properties. The amino acid compositions of PySp1 is obviously distinct from other spidroins. Our sequence makes an important contribution to understand pyriform silk protein structure and also provides a new template for recombinant pyriform silk proteins with attractive properties.
蜘蛛通常会产生多种类型的丝，每种丝都具有独特的性质，适合特定的任务和生物功能。园蛛科蜘蛛可以产生超过六种类型的丝纤维蛋白，其中梨形丝用于形成附着盘，将丝附着在其他表面和物质上。丝纤维蛋白的独特高级结构被认为是其卓越的生物力学特性的来源。即便如此，目前仅报道了 种的梨形丝蛋白 1 (PySp1) 的一个全长基因序列，并且对天然梨形丝纤维的力学性能的研究也很缺乏。为了更好地了解 PySp1 基因家族，我们使用长距离 PCR (LD-PCR) 来确定 种的 PySp1 序列。这个全长的 PySp1 基因长 11931bp，编码非重复的 N-和 C-末端域中的 3976 个氨基酸残基，具有一个由 16 个非常均匀的单元组成的中央大部分重复区域。这与先前报道的 PySp1 序列相似， 种的 PySp1 也具有长的重复 N-接头，连接 N-末端和重复区域。 PySp1 的二级结构和疏水性预测显示了梨形丝纤维的功能特性。PySp1 的氨基酸组成明显不同于其他丝蛋白。我们的序列对理解梨形丝蛋白结构做出了重要贡献，也为具有吸引力的重组梨形丝蛋白提供了新的模板。
