聚（A）·聚（U）对小鼠单核细胞/巨噬细胞系J774A1的激活作用：I. 聚（A）·聚（U）的结合及寡聚2'，5'-腺苷酸合成酶的诱导

Activation of the murine monocyte/macrophage cell line, J774A1 by poly(A).poly(U): I. Binding of poly(A).poly(U) and induction of oligo-2',5'-adenylate synthetase.

作者信息

Marin J G, Rodrigue F, Mencia-Huerta J M, Chabrier P E, Braquet P

机构信息

Institut Henri Beaufour 1, Les Ulis, France.

出版信息

Biochim Biophys Acta. 1993 Jul 28;1178(1):103-10. doi: 10.1016/0167-4889(93)90115-6.

DOI:10.1016/0167-4889(93)90115-6

PMID:8329455

Abstract

Binding and internalization of the synthetic double-stranded complex poly(A).poly(U) were studied on a murine monocyte/macrophage cell line J774A1. Poly(A).poly(U) increased in a dose-dependent fashion the oligo-2',5'-adenylate synthetase demonstrating that those cells were responsive to this agonist. Binding of [32P]poly(A).[32P]poly(U) to the cells reached an apparent kinetic equilibrium within 4 h and was saturable (apparent Kd = 9.99 +/- 0.09.10(-2) g/l and Bmax 13.3 +/- 5.3.10(-3) g/l per 10(6) cells) and temperature-dependent. The binding of poly(A).poly(U) was competitively inhibited by various polynucleotides but not by other structurally unrelated compounds. Analysis of cell-associated [32P]poly(A).[32P]poly(U) demonstrated a minimal degradation of this polyribonucleotide over a 4-h incubation period. Autoradiography of cells incubated with [3H]poly(A).[3H]poly(U) revealed that poly(A).poly(U) was internalized and migrated to cell nuclei. These results suggest that poly(A).poly(U) is internalized in J774A1 cells via an endocytotic process.

摘要

在小鼠单核细胞/巨噬细胞系J774A1上研究了合成双链复合物聚（A）·聚（U）的结合和内化。聚（A）·聚（U）以剂量依赖性方式增加寡聚2'，5'-腺苷酸合成酶，表明这些细胞对该激动剂有反应。[32P]聚（A）·[32P]聚（U）与细胞的结合在4小时内达到明显的动力学平衡，且具有饱和性（每10^6个细胞的表观解离常数Kd = 9.99±0.09×10^(-2) g/l，最大结合量Bmax = 13.3±5.3×10^(-3) g/l），并且依赖于温度。聚（A）·聚（U）的结合受到各种多核苷酸的竞争性抑制，但不受其他结构不相关化合物的抑制。对细胞相关的[32P]聚（A）·[32P]聚（U）的分析表明，在4小时的孵育期内这种多聚核糖核苷酸的降解最小。用[3H]聚（A）·[3H]聚（U）孵育细胞的放射自显影显示聚（A）·聚（U）被内化并迁移到细胞核。这些结果表明聚（A）·聚（U）在J774A1细胞中通过内吞过程被内化。