Translation: in retrospect and prospect.

This review is occasioned by the fact that the problem of translation, which has simmered on the biological sidelines for the last 40 years, is about to erupt center stage--thanks to the recent spectacular advances in ribosome structure. This most complex, beautiful, and fascinating of cellular mechanisms, the translation apparatus, is also the most important. Translation not only defines gene expression, but it is the sine qua non without which modern (protein-based) cells would not have come into existence. Yet from the start, the problem of translation has been misunderstood--a reflection of the molecular perspective that dominated Biology of the last century. In that the our conception of translation will play a significant role in creating the structure that is 21st century Biology, it is critical that our current (and fundamentally flawed) view of translation be understood for what it is and be reformulated to become an all-embracing perspective about which 21st century Biology can develop. Therefore, the present review is both a retrospective and a plea to biologists to establish a new evolutionary, RNA-World-centered concept of translation. What is needed is an evolutionarily oriented perspective that, first and foremost, focuses on the nature (and origin) of a primitive translation apparatus, the apparatus that transformed an ancient evolutionary era of nucleic acid life, the RNA World, into the world of modern cells.