Variations on complexity.

TL;DR: The discovery of alternative splicing and RNA editing did away with the linear ‘gene‐to‐protein’ concept and now the authors know that a single gene can give rise to a variety of alternative products.

Abstract: Back in the early days of molecular biology, life was a simple equation: a segment of DNA was transcribed into messenger RNA that was, in turn, translated into protein. The combination and quantities of all the proteins expressed in a cell thus defined its characteristics. To understand life, we believed, we would need only to identify every protein and its function. With time, research demonstrated that this was far too simplistic a view of the complex processes of the cell. First, it became clear that genes sometimes have many promoters and therefore different controls on their expression. Similarly, the discovery of alternative splicing and RNA editing did away with the linear ‘gene‐to‐protein’ concept: now we know that a single gene can give rise to a variety of alternative products. However, the biggest complications come from post‐translational protein modifications. Reversible …