THE UBIQUITOUS OCTAMER-BINDING PROTEIN OCT-1 CONTAINS A POU DOMAIN WITH A HOMEO BOX SUBDOMAIN
THE UBIQUITOUS OCTAMER-BINDING PROTEIN OCT-1 CONTAINS A POU DOMAIN WITH A HOMEO BOX SUBDOMAIN
复制标题
DOI：
10.1101/gad.2.12a.1582
复制
发表时间：
1988-12-01
影响因子：
10.5
通讯作者：
HERR, W
中科院分区：
文献类型：
--
作者：
STURM, RA;DAS, G;HERR, W
八聚体基序ATGCAAAT被两种哺乳动物转录因子识别：一种是普遍表达的Oct-1，另一种是在淋巴样细胞中表达的Oct-2。我们通过筛选.lambda，报道了编码oct-1的人oct-1基因的cDNA克隆。gt11重组噬菌体原位八聚体特异性DNA结合。.lambda之一。重组Gt11表达一个。β。-半乳糖苷酶-八聚体结合融合蛋白，具有与人HeLa细胞Oct-1蛋白难以区分的dna结合特异性。作为一种普遍表达的蛋白，Oct-1 mRNA在所有五种人类和两种小鼠细胞系中均有表达。兔多克隆抗血清抗。-半乳糖苷酶融合蛋白表明Oct-1和Oct-2蛋白的dna结合域具有抗原性。对全长743个氨基酸的oct-1开放阅读框的缺失分析表明，其dna结合活性位于160个氨基酸的中心高电荷结构域内。Oct-1和Oct-2序列的比较表明，这两个蛋白之间的结构域几乎相同。高度相似的结构域也存在于垂体特异性转录因子Pit-1和秀丽隐杆线虫unc-86细胞系基因产物中（见Herr et al. 1988）。在这个共享的POU （Pit-1， Oct-1和Oct-2， unc-86）域（发音为“pow”）中有两个子域：与POU相关的homeo盒和特定于POU的盒。Oct-1蛋白是一种独特的蛋白，因为它的表达无处不在。
The octamer motif ATGCAAAT is recognized indistinguishably by two mammalian transcription factors: one that is expressed ubiquitously and referred to here as Oct-1, and another, Oct-2, that is expressed in lymphoid cells. We report the cDNA cloning of the human oct-1 gene, which encodes Oct-1, by screening .lambda. gt11 recombinant phage in situ for octamer motif-specific DNA binding. One .lambda. gt11 recombinant expressed a .beta.-galactosidase-octamer-binding fusion protein with a DNA-binding specificity indistinguishable from human HeLa cell Oct-1 protein. As expected for a ubiquitously expressed protein, Oct-1 mRNA is expressed in all five human and two mouse cell lines tested. Polyclonal rabbit antiserum raised against the .beta.-galactosidase fusion protein shows that the DNA-binding domains of Oct-1 and Oct-2 proteins are related antigenically. Deletion analysis of the 743-amino-acid-long oct-1 open reading frame shows that the DNA-binding activity lies within a central highly charged domain of 160 amino acids. Comparison of the Oct-1 and Oct-2 sequences reveals that this domain is nearly identical between the two proteins. Highly similar domains are also present in the pituitary-specific transcription factor Pit-1 and the Caenorhabditis elegans unc-86 cell lineage gene product (see Herr et al. 1988). Within this shared POU (Pit-1, Oct-1 and Oct-2, unc-86) domain (pronounced ''pow'') lie two subdomains: a POU-related homeo box and a POU-specific box. The Oct-1 protein is unique among the POU-related proteins and other homeo box proteins because it is expressed ubiquitously.