Batista J A, Teixeira S M, Donelson J E, Kirchhoff L V, de Sá C M
Departamento de Biologia Celular, Universidade de Brasilia, Brazil.
Mol Biochem Parasitol. 1994 Oct;67(2):301-12. doi: 10.1016/0166-6851(94)00133-2.
We have characterized the biochemical properties of a 66-kDa poly(A)-binding protein (PABP1) in the protozoan Trypanosoma cruzi and isolated two classes of cDNAs encoding the protein. In concordance, Southern blots showed the presence of 2 gene copies. The two cDNA classes differ in the length of adenosine-rich segments in the 5' untranslated region and in point changes scattered throughout the sequence, but their 1650-bp open reading frames encode identical proteins. A single mRNA of 5.5 kb was detected, indicating that the noncoding regions are unusually long. Both the mRNA and the protein are constitutively expressed in all stages of T. cruzi life cycle. The biochemical properties and sequence comparisons show that the T. cruzi PABP1 is similar to the PABP1 of other eukaryotic organisms. These results indicate that PABP1 has been conserved throughout eukaryotic evolution.
我们已经对原生动物克氏锥虫中一种66 kDa的聚腺苷酸结合蛋白（PABP1）的生化特性进行了表征，并分离出了两类编码该蛋白的cDNA。与此一致的是，Southern杂交显示存在2个基因拷贝。这两类cDNA在5'非翻译区富含腺苷的片段长度以及整个序列中散布的点突变方面存在差异，但它们1650 bp的开放阅读框编码相同的蛋白质。检测到一条5.5 kb的单一mRNA，表明非编码区异常长。mRNA和蛋白质在克氏锥虫生命周期的所有阶段均组成性表达。生化特性和序列比较表明，克氏锥虫PABP1与其他真核生物的PABP1相似。这些结果表明，PABP1在整个真核生物进化过程中一直保守。
