MIF protein are theta-class glutathione S-transferase homologs.
MIF protein are theta-class glutathione S-transferase homologs.
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MIF 蛋白是 theta 类谷胱甘肽 S-转移酶同系物。
DOI：
10.1002/pro.5560021210
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Wackett,LP
中科院分区：
文献类型：
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作者：
Blocki,FA;Ellis,LB;Wackett,LP
MIF蛋白是一种哺乳动物多肽，分子量约为13,000。这一类包括人巨噬细胞移动抑制因子(MIF)，一种具有谷胱甘肽S转移酶(GST)活性的大鼠肝脏蛋白(TRANSMIF)和小鼠延迟早期反应基因6(DER6)蛋白。MIF蛋白以前通过证明转移酶活性和观察N-末端序列与MU类GST的同源性而与GST相连(Blocki，EA，Schlievert，PM，&Wackett，LP，1992，Nature360,269-270)。在这项研究中，MIF蛋白被证明在结构上与GSTs的theta类有关。这是通过三种方式建立起来的。首先，为每个GST基因类别开发出唯一的初级序列模式。这些模式确定这三个MIF蛋白是theta样转移酶同源物。其次，模式分析表明，在已知结构的GST中，theta类的GST成员含有丝氨酸残基，而不是与谷胱甘肽去质子化和激活有关的N末端酪氨酸(Liu，S.，等人，1992，J.Biol)。化学。267、4296-4299)。MIF蛋白在这个位置含有苏氨酸。第三，针对重组人MIF的多克隆抗体在Western blotts上与大鼠theta GST发生交叉反应，但不与αGST和Mu GST发生交叉反应。MIF蛋白具有谷胱甘肽结合能力，这可能为理解这个广泛分布的新兴基因家族的各种功能提供了一个共同的结构关键。由于theta被认为是最古老的进化GST类，MIF蛋白可能在进化早期出现了分歧，但保留了谷胱甘肽结合域。
MIF proteins are mammalian polypeptides of approximately 13,000 molecular weight. This class includes human macrophage migration inhibitory factor (MIF), a rat liver protein that has glutathione S-transferase (GST) activity (TRANSMIF), and the mouse delayed early response gene 6 (DER6) protein. MIF proteins were previously linked to GSTs by demonstrating transferase activity and observing N-terminal sequence homology with a mu-class GST (Blocki, EA., Schlievert, PM, & Wackett, LP, 1992, Nature360, 269-270). In this study, MIF proteins are shown to be structurally related to the theta class of GSTs. This is established in three ways. First, unique primary sequence patterns are developed for each of the GST gene classes. The patterns identify the three MIF proteins as theta-like transferase homologs. Second, pattern analysis indicates that GST members of the theta class contain a serine residue in place of the N-terminal tyrosine that is implicated in glutathione deprotonation and activation in GSTs of known structure (Liu, S., et al., 1992, J. Biol. Chem. 267, 4296-4299). The MIF proteins contain a threonine at this position. Third, polyclonal antibodies raised against recombinant human MIF crossreact on Western blots with rat theta GST but not with alpha and mu GSTs. That MIF proteins have glutathionebinding ability may provide a common structural key toward understanding the varied functions of this widely distributed emerging gene family. Because theta is thought to be the most ancient evolutionary GST class, MIF proteins may have diverged early in evolution but retained a glutathione-binding domain.