Ray B K, Lawson T G, Abramson R D, Merrick W C, Thach R E
J Biol Chem. 1986 Sep 5;261(25):11466-70.
The ability of polypeptide components of eukaryotic initiation factor (eIF) 4F to bind to the m7G cap of an mRNA, to be released from that mRNA, and then to rebind to the cap of a second mRNA has been investigated. The release and rebinding steps have been termed "recycling." It was found that eIF-4B stimulates the recycling of the 24-26 kDa (p24) component of eIF-4F, and perhaps of other components as well. By contrast, eIF-4A seemed to have little or no effect on the recycling of eIF-4F components, either in the presence or absence of eIF-4B. The recycled p24 is capable of cross-linking to oxidized cap structures. The recycled factor is also able to stimulate the cross-linking of added eIF-4A, which cross-links poorly in the absence of eIF-4F. By these criteria it seems likely that the recycled eIF-4F components are active for a second round of translational initiation.
真核生物起始因子（eIF）4F的多肽组分与mRNA的m7G帽结合、从该mRNA上释放然后再与第二个mRNA的帽重新结合的能力已得到研究。释放和重新结合步骤被称为“循环利用”。研究发现，eIF - 4B刺激eIF - 4F的24 - 26 kDa（p24）组分的循环利用，可能也刺激其他组分的循环利用。相比之下，无论有无eIF - 4B，eIF - 4A似乎对eIF - 4F组分的循环利用几乎没有影响。循环利用的p24能够与氧化的帽结构交联。循环利用的因子还能够刺激添加的eIF - 4A的交联，在没有eIF - 4F的情况下，eIF - 4A交联效果很差。根据这些标准，循环利用的eIF - 4F组分似乎有可能在第二轮翻译起始中发挥作用。
