Tutar Yusuf
Chemistry Department, Faculty of Science, Cumhuriyet University, Sivas 58140, Turkey.
Protein Pept Lett. 2006;13(7):699-705. doi: 10.2174/092986606777790593.
Hsp70 is a universally conserved essential protein chaperone. In addition to its roles in many cellular process, Hsp70 protects cells from stress by binding partially unfolded proteins. Therefore, Hsp70 prevents protein aggregation and prion formation. Prions are infectious agents and are responsible for several fatal neurodegenerative diseases. Eukaryotic cells have several cytosolic Hsp70 isoforms, some constitutively expressed (Hsc70s), and others expressed only when cells are exposed to stress (Hsp70s). To determine which factors conferred functional specificity, we constructed hybrid Hsc/Hsp chaperones. All hybrids supported growth except those that contained the ATPase domain derived from inducible Hsp70. Thus, regulation of peptide binding by ATP hydrolysis must differ significantly between Hsc- and Hsp70 isoforms. In this work, nucleotide and peptide binding domain communication of Hsp70 proteins during their interaction with nucleotides and peptide substrates were investigated in vitro by using hybrid constructs.
热休克蛋白70（Hsp70）是一种普遍保守的必需蛋白伴侣。除了在许多细胞过程中发挥作用外，Hsp70还通过结合部分未折叠的蛋白质来保护细胞免受应激。因此，Hsp70可防止蛋白质聚集和朊病毒形成。朊病毒是感染因子，可导致几种致命的神经退行性疾病。真核细胞有几种胞质Hsp70亚型，一些是组成性表达的（Hsc70s），另一些仅在细胞受到应激时才表达（Hsp70s）。为了确定哪些因素赋予了功能特异性，我们构建了杂交Hsc/Hsp伴侣蛋白。除了那些含有源自诱导型Hsp70的ATP酶结构域的杂交蛋白外，所有杂交蛋白都支持细胞生长。因此，Hsc70和Hsp70亚型之间通过ATP水解对肽结合的调节必定存在显著差异。在这项工作中，我们使用杂交构建体在体外研究了Hsp70蛋白在与核苷酸和肽底物相互作用过程中核苷酸和肽结合结构域之间的通讯。
