Department of Chemical and Biological Engineering, University of California, Berkeley, CA, USA.
School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia.
Adv Exp Med Biol. 2018;1106:11-23. doi: 10.1007/978-3-030-00737-9_2.
Molecular chaperones promote the correct folding of proteins in aggregation-prone cellular environments by stabilizing nascent polypeptide chains and providing appropriate folding conditions. Prefoldins (PFDs) are molecular chaperones found in archaea and eukaryotes, generally characterized by a unique jellyfish-like hexameric structure consisting of a rigid beta-barrel backbone with protruding flexible coiled-coils. Unlike eukaryotic PFDs that mainly interact with cytoskeletal components, archaeal PFDs can stabilize a wide range of substrates; such versatility reflects PFD's role as a key element in archaeal chaperone systems, which often lack general nascent-chain binding chaperone components such as Hsp70. While archaeal PFDs mainly exist as hexameric complexes, their structural diversity ranges from tetramers to filamentous oligomers. PFDs bind and stabilize nonnative proteins using varying numbers of coiled-coils, and subsequently transfer the substrate to a group II chaperonin (CPN) for refolding. The distinct structure and specific function of archaeal PFDs have been exploited for a broad range of applications in biotechnology; furthermore, a filament-forming variant of PFD has been used to fabricate nanoscale architectures of defined shapes, demonstrating archaeal PFDs' potential applicability in nanotechnology.
分子伴侣通过稳定新生多肽链并提供适当的折叠条件，促进在易于聚集的细胞环境中蛋白质的正确折叠。原初折叠蛋白（PFDs）是在古菌和真核生物中发现的分子伴侣，通常具有独特的水母样六聚体结构，由刚性的β-桶状骨架和突出的柔性卷曲螺旋组成。与主要与细胞骨架成分相互作用的真核 PFD 不同，古菌 PFD 可以稳定广泛的底物；这种多功能性反映了 PFD 在古菌伴侣系统中的关键作用，古菌伴侣系统通常缺乏一般的新生链结合伴侣成分，如 Hsp70。虽然古菌 PFD 主要以六聚体复合物的形式存在，但它们的结构多样性从四聚体到丝状寡聚体不等。PFD 使用不同数量的卷曲螺旋结合并稳定非天然蛋白质，然后将底物转移到第二组伴侣蛋白（CPN）进行重折叠。古菌 PFD 的独特结构和特定功能已被广泛应用于生物技术；此外，PFD 的丝状形成变体已被用于制造具有特定形状的纳米尺度结构，证明了古菌 PFD 在纳米技术中的潜在适用性。
