Solari A, Gatica M
Biochem Int. 1984 Jun;8(6):831-41.
Nuclei and enucleated Xenopus laevis oocytes were used as a source of exonucleases that hydrolyze the 3'terminus sequence of tRNA. The majority of the total activity was found in the cytoplasm. Several forms of enzyme activity are obtained upon fractionation in S-200 column. Both nuclear and cytoplasmic activities display a preferential cleavage of the terminal AMP residue. Similar results are obtained in vivo by microinjection of tRNA labelled in the CCA sequence. Aminoacylation of tRNA, on the other hand, protects the terminal nucleotide against exonuclease activity.
细胞核和去核的非洲爪蟾卵母细胞被用作外切核酸酶的来源，这些外切核酸酶可水解tRNA的3'末端序列。总活性的大部分存在于细胞质中。在S-200柱上进行分级分离时可获得几种酶活性形式。细胞核和细胞质活性均表现出对末端AMP残基的优先切割。通过显微注射在CCA序列中标记的tRNA在体内也可获得类似结果。另一方面，tRNA的氨酰化作用可保护末端核苷酸免受外切核酸酶活性的影响。
