Effects of heme addition on formation of stable human globin chains and hemoglobin subunit assembly in a cell-free system.
Effects of heme addition on formation of stable human globin chains and hemoglobin subunit assembly in a cell-free system.
复制标题
添加血红素对无细胞系统中稳定的人珠蛋白链形成和血红蛋白亚基组装的影响。
DOI：
10.1016/s0003-9861(03)00089-4
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发表时间：
2003
影响因子：
3.9
通讯作者：
Surrey,Saul
中科院分区：
文献类型：
--
作者：
Adachi,Kazuhiko;Zhao,Yi;Surrey,Saul
我们先前使用偶联的转录/翻译无细胞系统进行的形成血红蛋白异源二聚体和四聚体的组装研究表明，α-珠蛋白链在翻译期间和/或翻译后不久与新生的非α链结合，以促进血红蛋白形成[阿达奇等人，2002（277）13415]。在这份报告中，CN-氯化血红素亚基组装的影响进行了研究，使用这种无细胞系统。在合成过程中加入CN-氯化血红素和过量未标记的含血红素配偶体链，导致形成放射性标记的含血红素αhβ h异源二聚体。相反，在不添加CN-氯化血红素的情况下，未标记的含血红素α或β链可与新合成的放射性标记的β和α珠蛋白链组装，分别形成含血红素αhβ和半α（αhβ0）或半β（α0βh）异源二聚体。这些结果表明在含血红素的αhβ链形成之前存在半血红蛋白作为中间体，并且表明血红素从α和/或β链转移到半血红蛋白异源二聚体中以形成含血红素的异源二聚体。
Our previous assembly studies to form hemoglobin hetero-dimers and -tetramers using a coupled transcription/translation cell-free system suggested that α-globin chains bind to nascent non-α chains during and/or soon after translation to promote hemoglobin formation [Adachi et al., J. Biol Chem. 2002 (277) 13415]. In this report effects of CN–hemin on subunit assembly were studied using this cell-free system. Addition of CN–hemin and excess unlabeled heme-containing partner chains during synthesis leads to formation of radiolabeled heme-containing αhβhhetero-dimers. In contrast, in the absence of added CN–hemin, unlabeled heme-containing α or β chains can assemble with newly synthesized radiolabeled β- and α-globin chains to form heme-containing αhβhand semi-α (αhβ0) or semi-β (α0βh) hetero-dimers, respectively. These results suggest the existence of semi-hemoglobins as intermediates prior to formation of heme-containing αhβhand indicate transfer of heme from α and/or β chains into semi-hemoglobin hetero-dimers to form heme-containing hetero-dimers.