It is widely accepted that protein synthesis occurs in the cytoplasms of eukaryotic cells, but some investigators believe that it also occurs in the nucleus. In spite of experiments performed in several labs over many years, the issue of nuclear translation remains unresolved. Advocates assert that it would serve as an economical and convenient way to explain how cells monitor the quality of newly made mRNAs or ribosomes. Skeptics argue that regardless of its esthetic appeal, compelling evidence for nuclear translation has been absent. The key question--also central to the debate more than 30 years ago--is whether alleged nuclear translation can be proven to represent "genuine polypeptide synthesis that is a function of the nuclear compartment".