Fabre E, Boelens W C, Wimmer C, Mattaj I W, Hurt E C
European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany.
Cell. 1994 Jul 29;78(2):275-89. doi: 10.1016/0092-8674(94)90297-6.
An essential yeast protein, Nup145p, is identified via its genetic interaction with the nucleoporin Nsp1p. Nup145p contains GLFG repeats and localizes to nuclear pores. Depletion of Nup145p in vivo leads rapidly to nuclear retention of polyadenylated RNAs and more slowly to cytoplasmic accumulation of a nuclear reporter protein. A stretch of 140 amino acids within Nup145p is conserved in two other yeast nucleoporins, Nup116p and Nup100p, and in an uncharacterized C. elegans protein. Genetic experiments in yeast reveal that the three copies of the motif carry out an essential, redundant function. Fragments of Nup145p and Nup116p including this motif bind specifically to homopolymeric RNAs in vitro. Nup145p, Nup116p, and Nup100p thus represent a novel class of nucleoporins involved in nucleocytoplasmic transport.
一种重要的酵母蛋白Nup145p，是通过其与核孔蛋白Nsp1p的遗传相互作用而被鉴定出来的。Nup145p含有GLFG重复序列，并定位于核孔。体内Nup145p的缺失会迅速导致多聚腺苷酸化RNA在细胞核内滞留，而使一种核报告蛋白在细胞质中积累的速度则较慢。Nup145p内一段140个氨基酸的序列在另外两种酵母核孔蛋白Nup116p和Nup100p以及一种未鉴定的秀丽隐杆线虫蛋白中是保守的。酵母中的遗传实验表明，该基序的三个拷贝执行一种必需的冗余功能。包含该基序的Nup145p和Nup116p片段在体外能特异性结合同聚RNA。因此，Nup145p、Nup116p和Nup100p代表了一类参与核质运输的新型核孔蛋白。
