Drosophila AP3, a presumptive DNA repair protein, is homologous to human ribosomal associated protein P0.
Drosophila AP3, a presumptive DNA repair protein, is homologous to human ribosomal associated protein P0.
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果蝇 AP3 是一种假定的 DNA 修复蛋白，与人核糖体相关蛋白 P0 同源。
作者：
D. Grabowski;W. A. Deutsch;Dennis Derda;M. Kelley
使用先前使用针对人脱嘌呤/脱嘧啶（AP）内切核酸酶的抗体分离的果蝇基因（AP 3）（1，8）来筛选HeLa cDNA文库中的其人同源物。一个人类基因被分离出来，它编码的蛋白质在氨基酸水平上与果蝇AP 3基因有66%的相同性和79%的相似性，并且与人类蛋白质PO相同（2）。PO基因是用系统性红斑狼疮抗体克隆的，编码一种假定的核糖体相关蛋白（2）。果蝇和人蛋白的长度相同，均为317个氨基酸，并且具有在酵母（AO;3）、大鼠（4）、小鼠（5）和人（2）的PO蛋白中观察到的特征性酸性羧基尾（图1）。果蝇蛋白也含有一个23个氨基酸的区域，类似于E.大肠杆菌L1 O蛋白与28 S rRNA分子的结合有关（3）（图2）。AP 3与人PO（66%-无缺口）、大鼠PO（66%-无缺口）和小鼠PO（66%-无缺口）在氨基酸水平上具有最大的同源性，但与酵母AO同源性较低（52%-两个缺口）。果蝇蛋白质约为34，000道尔顿，具有大量丙氨酸（317个氨基酸中的37个或12%），其位于蛋白质的羧基末端，类似于PO蛋白质（2，3，4，5）。虽然真核生物
A Drosophila gene (AP3), previously isolated using antibody to a human apurinic/apyrimidinic (AP) endonuclease (1, 8) was used to screen a HeLa cDNA library for its human homolog. One human gene was isolated that encodes a protein that is 66% identical and 79% similar at the amino acid level to the Drosophila AP3 gene, and is identical to the human protein PO (2). The PO gene was cloned using antibodies to systemic lupus erythematosus, and encodes a presumptive ribosomal associated protein (2). Both the Drosophila and human proteins are the same length, 317 amino acids, and have the characteristic acidic carboxy tail seen in PO proteins from yeast (AO;3), rat (4) mouse (5) and human (2) (Figure 1). The Drosophila protein also contains a 23 amino acid region similar to a region in the E. coli L1O protein that has been implicated in the binding of 28S rRNA molecules (3) (Figure 2). AP3 shares the greatest homology at the amino acid level to human PO (66%-no gaps), rat PO (66%-no gaps) and mouse PO (66%-no gaps), but is less homologous to the yeast AO (52%-two gaps). The Drosophila protein is approximately 34,000 Daltons and has a large number of alanines (37 or 12% of the 317 amino acids) which are located in the carboxy terminus of the protein, similar to PO proteins (2, 3, 4, 5). Although the eukaryotic