[Functional anatomy of the gene: from gene to protein]

Over the last 20 years what we knew about genes and their expression has considerably evolved. The coding part of the gene is split in several exons separated by introns, and preceded by a region of variable size that allows the regulation of its expression. From a functional point of view the genes is transcribed into a messenger ribonucleic acid which undergoes a maturation process. This maturation enables to excise the introns and to add a cap and a tail consisting of a poly A. Finally the messenger is transcribed into a protein. All these steps undergo multiple and complex regulations.