2M0M

Structural Characterization of Minor Ampullate Spidroin Domains and their Distinct Roles in Fibroin Solubility and Fiber Formation

2M0M の概要

• エントリーDOI: 10.2210/pdb2m0m/pdb
• NMR情報: BMRB: 18811
• 分子名称: Minor ampullate fibroin 1 (1 entity in total)
• 機能のキーワード: spider silk protein, misp1, ctd, dimer, protein fibril
• 由来する生物種: Nephila antipodiana
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 21011.40

構造登録者

Yang, D.,Gao, Z.,Lin, Z.,Huang, W.,Lai, C.,Fan, J. (登録日: 2012-10-30, 公開日: 2013-03-27, 最終更新日: 2024-05-01)

主引用文献

Gao, Z.,Lin, Z.,Huang, W.,Lai, C.C.,Fan, J.S.,Yang, D.
Structural characterization of minor ampullate spidroin domains and their distinct roles in fibroin solubility and fiber formation
Plos One, 8:e56142-e56142, 2013

PubMed Abstract: Spider silk is protein fibers with extraordinary mechanical properties. Up to now, it is still poorly understood how silk proteins are kept in a soluble form before spinning into fibers and how the protein molecules are aligned orderly to form fibers. Minor ampullate spidroin is one of the seven types of silk proteins, which consists of four types of domains: N-terminal domain, C-terminal domain (CTD), repetitive domain (RP) and linker domain (LK). Here we report the tertiary structure of CTD and secondary structures of RP and LK in aqueous solution, and their roles in protein stability, solubility and fiber formation. The stability and solubility of individual domains are dramatically different and can be explained by their distinct structures. For the tri-domain miniature fibroin, RP-LK-CTD(Mi), the three domains have no or weak interactions with one another at low protein concentrations (<1 mg/ml). The CTD in RP-LK-CTD(Mi) is very stable and soluble, but it cannot stabilize the entire protein against chemical and thermal denaturation while it can keep the entire tri-domain in a highly water-soluble state. In the presence of shear force, protein aggregation is greatly accelerated and the aggregation rate is determined by the stability of folded domains and solubility of the disordered domains. Only the tri-domain RP-LK-CTD(Mi) could form silk-like fibers, indicating that all three domains play distinct roles in fiber formation: LK as a nucleation site for assembly of protein molecules, RP for assistance of the assembly and CTD for regulating alignment of the assembled molecules.

PubMed: 23418525
DOI: 10.1371/journal.pone.0056142

実験手法

SOLUTION NMR