Kanaar R, Roche S E, Beall E L, Green M R, Rio D C
Department of Molecular and Cell Biology, University of California, Berkeley 94720.
Science. 1993 Oct 22;262(5133):569-73. doi: 10.1126/science.7692602.
The large subunit of the human pre-messenger RNA splicing factor U2 small nuclear ribonucleoprotein auxiliary factor (hU2AF65) is required for spliceosome assembly in vitro. A complementary DNA clone encoding the large subunit of Drosophila U2AF (dU2AF50) has been isolated. The dU2AF50 protein is closely related to its mammalian counterpart and contains three carboxyl-terminal ribonucleoprotein consensus sequence RNA binding domains and an amino-terminal arginine- and serine-rich (R/S) domain. Recombinant dU2AF50 protein complements mammalian splicing extracts depleted of U2AF activity. Germline transformation of Drosophila with the dU2AF50 complementary DNA rescues a lethal mutation, establishing that the dU2AF50 gene is essential for viability. R/S domains have been found in numerous metazoan splicing factors, but their function is unknown. The mutation in Drosophila U2AF will allow in vivo analysis of a conserved R/S domain-containing general splicing factor.
人前体信使核糖核酸剪接因子U2小核核糖核蛋白辅助因子（hU2AF65）的大亚基是体外剪接体组装所必需的。已分离出编码果蝇U2AF大亚基（dU2AF50）的互补DNA克隆。dU2AF50蛋白与其哺乳动物对应物密切相关，包含三个羧基末端核糖核蛋白共有序列RNA结合结构域和一个氨基末端富含精氨酸和丝氨酸的（R/S）结构域。重组dU2AF50蛋白可补充缺乏U2AF活性的哺乳动物剪接提取物。用dU2AF50互补DNA对果蝇进行种系转化可挽救致死突变，证明dU2AF50基因对生存力至关重要。R/S结构域已在许多后生动物剪接因子中发现，但其功能尚不清楚。果蝇U2AF中的突变将允许对含保守R/S结构域的一般剪接因子进行体内分析。
