真核起始因子1

真核起始因子1
	人類eIF1的溶液結構
識別
符號	eIF1
替換符號	SUI1（酵母中）
Entrez	10209
PDB	2if1
RefSeq	NP_005792
UniProt	P41567
其他資料
基因座	17 [1]

eIF1（eukaryotic initiation factor 1，真核起始因子1）是一種參與真核翻譯起始的重要的蛋白質。eIF1在起始密碼子AUG的識別中發揮重要的作用，它能使起始密碼子的識別具有很高的保真度。

在酵母中，eIF1是維持其生存不可或缺的蛋白質。^[1]

功能機制[編輯]

eIF1結合在40S核糖體亞基的表面，可能影響在48前起始複合物中40S亞基的表面構象及mRNA和Met-tRNA_i的結合位置。在密碼子與反密碼子沒有正確配對時，eIF1可以抑制GTP的水解，當密碼子的識別完成後，eIF1的抑制作用被減弱，並且實驗發現eIF1的抑制作用的減弱需要精確的AUG的配對，而其它例如UUG或CAA的識別並沒有類似功能。^[2]

結構[編輯]

eIF1結構屬於α+β型摺疊，包含了一個由5個β鏈組成的β摺疊片和兩個α螺旋組成的結構域，其N末端為一段較長的無結構區域。^[3]^[4]eIF1被發現能夠以不同的蛋白質表面與40S核糖體亞基以及eIF2、eIF3和eIF5結合。^[4]

參考文獻[編輯]

^ （英文）Yoon H and Donahue TF. The sui1 supressor locus in Saccharomyces cerevisiae encodes a translation factor that functions during tRNA_i^Met recognition of the start codon. Mol Cell Biol. 1992, 12: 248–260.
^ （英文）Unbehaun, A., Borukhov, S. I., Hellen, C. U. & Pestova, T. V. Release of initiation factors from 48S complexes during ribosomal subunit joining and the link between establishment of codon-anticodon base-pairing and hydrolysis of eIF2-bound GTP. Genes Dev. 2004, 18: 3078–93.
^ （英文）Fletcher CM, Pestova TV, Hellen CU, Wagner G. Structure and interactions of the translation initiation factor eIF1. EMBO J. 1999, 18: 2631–7. PMID 10228174.
^ ^4.0 ^4.1 （英文）Reibarkh M, Yamamoto Y, Singh CR, del Rio F, Fahmy A, Lee B, Luna RE, Ii M, Wagner G, Asano K. Eukaryotic initiation factor (eIF) 1 carries two distinct eIF5-binding faces important for multifactor assembly and AUG selection. J Biol Chem. 2007, 283: 1094–103. PMID 17974565.

參見[編輯]

真核起始因子
核糖體
eIF1A
能夠與eIF1結合的真核起始因子：
- eIF2
- eIF3
- eIF5

外部連結[編輯]

eIF1的相關信息（頁面存檔備份，存於互聯網檔案館）

[1] （英文）Yoon H and Donahue TF. The sui1 supressor locus in Saccharomyces cerevisiae encodes a translation factor that functions during tRNA_i^Met recognition of the start codon. Mol Cell Biol. 1992, 12: 248–260.

[2] （英文）Unbehaun, A., Borukhov, S. I., Hellen, C. U. & Pestova, T. V. Release of initiation factors from 48S complexes during ribosomal subunit joining and the link between establishment of codon-anticodon base-pairing and hydrolysis of eIF2-bound GTP. Genes Dev. 2004, 18: 3078–93.

[3] （英文）Fletcher CM, Pestova TV, Hellen CU, Wagner G. Structure and interactions of the translation initiation factor eIF1. EMBO J. 1999, 18: 2631–7. PMID 10228174.

[yeast_structure-4] 4.0 ^4.1 （英文）Reibarkh M, Yamamoto Y, Singh CR, del Rio F, Fahmy A, Lee B, Luna RE, Ii M, Wagner G, Asano K. Eukaryotic initiation factor (eIF) 1 carries two distinct eIF5-binding faces important for multifactor assembly and AUG selection. J Biol Chem. 2007, 283: 1094–103. PMID 17974565.

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