Filipowicz W, Sierra J M, Ochoa S
Proc Natl Acad Sci U S A. 1975 Oct;72(10):3947-51. doi: 10.1073/pnas.72.10.3947.
The activity of IF-MP, a polypeptide chain initiation factor that forms a ternary complex with eukaryotic initiator Met-tRNA and GTP and promotes binding of the initiator to 40S ribosomes, is very low in undeveloped Artemia salina embryos but increases over 20-fold following resumption of development upon hydration of the cysts. The factor is present in both the ribosomal salt wash and high-speed-supernatant. Its specific activity is 50 times higher in the wash but its total activity is only about twice as high in the wash as in the supernatant. As is true of IF-MP from other eukaryotic sources, the A. salina factor is specific for eukaryotic Met-tRNAi and sensitive to SH-reagents, and its activity is GTP dependent.
IF-MP是一种多肽链起始因子,它与真核起始甲硫氨酰-tRNA和GTP形成三元复合物,并促进起始物与40S核糖体的结合。在未发育的卤虫胚胎中,IF-MP的活性非常低,但在囊肿水化后恢复发育时,其活性增加了20倍以上。该因子存在于核糖体盐洗物和高速上清液中。其比活性在洗物中高50倍,但其总活性在洗物中仅比在上清液中高约两倍。与来自其他真核生物来源的IF-MP一样,卤虫因子对真核甲硫氨酰-tRNAi具有特异性,对SH试剂敏感,并且其活性依赖于GTP。