Nucleolar function on formation, stability and translation of messenger RNA

Rex蛋白定位于htlv - 1感染细胞的核仁中，htlv - 1是一种引起成人t细胞白血病的人类逆转录病毒。我们研究了Rex蛋白在细胞核中的作用及其对信使rna的形成、稳定性、转运和翻译的影响。没有核核靶向信号（NOS）的Rex蛋白无法形成HTLV-I的未剪接gag-pro-pol信使RNA，这表明NOS是将某些类型的信使RNA从细胞核转运到细胞质所必需的。此外，另一种引起艾滋病的人类逆转录病毒HIV-1在Tat和Rev两个调控基因产物中也含有NOS。我们发现Tat和Rev蛋白的NOS对其功能至关重要。

The Rex protein is localized in the nucleoli of cells infected by HTLV-I, a human retrovirus causing adult T-cell leukemia. We studied roles of Rex protein in the nucleus and its effect on the formation, stability, transport and translation of messenger RNAS. The Rex protein without the nucleolar targeting signal (NOS) failed to form the unspliced gag-pro-pol messenger RNA of HTLV-I, indicating that the NOS is required for transporting certain type of messenger RNAs from nucleus to cytoplasm. Furthermore, another human retrovirus causing AIDS, HIV-1 contains the NOS in two regulatory gene products, Tat and Rev. We have found that the NOS of Tat and Rev proteins is essential for their functions.