Peltz S W, Hammell A B, Cui Y, Yasenchak J, Puljanowski L, Dinman J D
The Cancer Institute of New Jersey, Piscataway, New Jersey 08854, USA.
Mol Cell Biol. 1999 Jan;19(1):384-91. doi: 10.1128/MCB.19.1.384.
Programmed -1 ribosomal frameshifting is utilized by a number of RNA viruses as a means of ensuring the correct ratio of viral structural to enzymatic proteins available for viral particle assembly. Altering frameshifting efficiencies upsets this ratio, interfering with virus propagation. We have previously demonstrated that compounds that alter the kinetics of the peptidyl-transfer reaction affect programmed -1 ribosomal frameshift efficiencies and interfere with viral propagation in yeast. Here, the use of a genetic approach lends further support to the hypothesis that alterations affecting the ribosome's peptidyltransferase activity lead to changes in frameshifting efficiency and virus loss. Mutations in the RPL3 gene, which encodes a ribosomal protein located at the peptidyltransferase center, promote approximately three- to fourfold increases in programmed -1 ribosomal frameshift efficiencies and loss of the M1 killer virus of yeast. The mak8-1 allele of RPL3 contains two adjacent missense mutations which are predicted to structurally alter the Mak8-1p. Furthermore, a second allele that encodes the N-terminal 100 amino acids of L3 (called L3Delta) exerts a trans-dominant effect on programmed -1 ribosomal frameshifting and killer virus maintenance. Taken together, these results support the hypothesis that alterations in the peptidyltransferase center affect programmed -1 ribosomal frameshifting.
程序性 -1 核糖体移码被多种RNA病毒用作一种手段，以确保用于病毒粒子组装的病毒结构蛋白与酶蛋白的比例正确。改变移码效率会打乱这种比例，干扰病毒繁殖。我们之前已经证明，改变肽基转移反应动力学的化合物会影响程序性 -1 核糖体移码效率，并干扰酵母中的病毒繁殖。在这里，使用遗传方法进一步支持了这样的假设，即影响核糖体肽基转移酶活性的改变会导致移码效率的变化和病毒损失。RPL3基因中的突变，该基因编码位于肽基转移酶中心的一种核糖体蛋白，会使程序性 -1 核糖体移码效率提高约三到四倍，并导致酵母的M1杀伤病毒丧失。RPL3的mak8-1等位基因包含两个相邻的错义突变，预计会在结构上改变Mak8-1p。此外，编码L3的N端100个氨基酸的第二个等位基因（称为L3Delta）对程序性 -1 核糖体移码和杀伤病毒维持具有反式显性作用。综上所述，这些结果支持了肽基转移酶中心的改变会影响程序性 -1 核糖体移码的假设。
