Sarkar Saumendra N, Pandey Mitali, Sen Ganes C
Department of Molecular Biology, The Lerner Research Institute, Cleaveland Clinic Foundation, OH, USA.
Methods Mol Med. 2005;116:81-101. doi: 10.1385/1-59259-939-7:081.
Inhibition of protein synthesis by interferon treatment is mediated by two major pathways: the 2'-5'-linked oligoadenylates [2-5 (A)] synthetase-RNase L pathway and the double-stranded ribonucleic acid-dependent protein kinase-mediated pathway. 2-5 (A) synthetases are unique interferon-inducible enzymes that, upon activation by double-stranded RNA, polymerize adenosine triphosphate (ATP) to 2-5 (A) synthases. These 2-5 (A) synthetases bind and activate the latent RNase L, causing RNA degradation. In addition to the three major size classes of enzymatically active oligoadenylate synthetase proteins, at least one inactive oligoadenylate synthetase is known in human and mouse. Structure-function studies and recent crystal structure determination have identified several distinct sites in these proteins responsible for different biochemical functions. RNase L is the only known protein that binds to 2-5 (A) synthetases with very high affinity. Gene knockout studies of RNase L have identified its role in antiviral actions of interferon and in apoptosis. Recently, it has also been implicated in prostate cancer metastasis. In this chapter we describe several methodologies for studying biochemical and physiological properties of the 2-5 (A) synthetase-RNase L pathway.
2'-5'-连接的寡腺苷酸[2-5(A)]合成酶-RNase L途径和双链核糖核酸依赖性蛋白激酶介导的途径。2-5(A)合成酶是一类独特的干扰素诱导酶，在双链RNA激活后，将三磷酸腺苷(ATP)聚合成2-5(A)。这些2-5(A)合成酶结合并激活潜在的RNase L，导致RNA降解。除了三种主要大小类别的具有酶活性的寡腺苷酸合成酶蛋白外，在人和小鼠中还已知至少一种无活性的寡腺苷酸合成酶。结构-功能研究和最近的晶体结构测定已经在这些蛋白质中确定了几个负责不同生化功能的不同位点。RNase L是唯一已知的与2-5(A)合成酶以非常高的亲和力结合的蛋白质。RNase L的基因敲除研究已经确定了其在干扰素抗病毒作用和细胞凋亡中的作用。最近，它还与前列腺癌转移有关。在本章中，我们描述了几种研究2-5(A)合成酶-RNase L途径生化和生理特性的方法。
