Bossi L, Roth J R
Cell. 1981 Aug;25(2):489-96. doi: 10.1016/0092-8674(81)90067-2.
The frameshift suppressor sufJ acts to correct a set of +1 frameshift mutations having very different sequences at their mutant sites. This suppressor acts by reading a 4 base codon located near, but not at, the site of each suppressible mutation. Suppression thus necessitates out-of-phase translation of the short stretch of mRNA between the site of action of the suppressor tRNA and the site of the frameshift mutation. We have identified the site read by sufJ by mutationally creating a series of such sites in the neighborhood of a previously nonsuppressible frameshift mutation. Each of the newly generated sites was formed by base substitution. Four independently generated sites were analyzed by DNA sequencing. At each site the quadruplet codon ACCX was generated (where X is A, U or C). Thus sufJ is able to read a 4 base codon in which any of three bases is acceptable in the fourth position. This is the first frameshift suppressor that does not read a run of three repeated bases in the first three positions of its codon.
移码抑制基因sufJ可校正一组在突变位点具有非常不同序列的+1移码突变。这种抑制基因通过读取位于每个可抑制突变位点附近而非该位点本身的四碱基密码子来发挥作用。因此，抑制需要在抑制性tRNA的作用位点与移码突变位点之间的短片段mRNA进行错相位翻译。我们通过在先前不可抑制的移码突变附近通过突变创建一系列这样的位点，确定了sufJ读取的位点。每个新生成的位点都是通过碱基替换形成的。通过DNA测序分析了四个独立生成的位点。在每个位点都产生了四联体密码子ACCX（其中X为A、U或C）。因此，sufJ能够读取一个四碱基密码子，其中第四位的三个碱基中的任何一个都是可接受的。这是第一个在其密码子的前三个位置不读取三个重复碱基序列的移码抑制基因。
