Alberta J A, Rundell K, Stiles C D
Program in Cell and Developmental Biology, Harvard Medical School, Boston, Massachusetts 02115.
J Biol Chem. 1994 Feb 11;269(6):4532-8.
Single or multiple copies of the pentameric motif, AUUUA, are found in the 3'-untranslated domain of most immediate early mRNAs. A broad body of data links this 5-base element to the selective degradation of these mRNAs. However, AUUUA motifs are neither always necessary nor always sufficient to tag an mRNA for rapid degradation. Here, we describe a cytoplasmic, protease-sensitive factor in Balb/c3T3 cells that interacts with the 3'-untranslated region of c-myc mRNA. The factor recognizes a 39-base uridine-rich domain adjacent to, but distinct from, the c-myc AUUUA motif. In chimeric mRNA constructs, the 39-base binding element cooperates with adjacent sequence material to destabilize beta-globin mRNA.
在大多数立即早期mRNA的3'非翻译区中发现了五聚体基序AUUUA的单拷贝或多拷贝。大量数据将这个5碱基元件与这些mRNA的选择性降解联系起来。然而，AUUUA基序对于标记mRNA进行快速降解既不总是必需的，也不总是充分的。在这里，我们描述了Balb/c3T3细胞中的一种细胞质蛋白酶敏感因子，它与c-myc mRNA的3'非翻译区相互作用。该因子识别与c-myc AUUUA基序相邻但不同的富含39个碱基的尿苷结构域。在嵌合mRNA构建体中，39碱基结合元件与相邻序列物质协同作用，使β-珠蛋白mRNA不稳定。
