The need for purity

摘要

When the sequencing of the human genome was completed in 2001, researchers worldwide finally had the information that they needed to take on the more difficult task of identifying and characterizing all proteins within an organism — otherwise known as the proteome. In contrast to the relatively static nature of the genome, proteins live in a dynamic and cramped world, which differs from cell to cell and from second to second, and changes constantly through its interactions with the genome, other proteins and the environment. This situation became more complex with the finding that far fewer genes create the protein panoply than was previously predicted. As mechanisms such as alternative splicing and post-translational modification create diversity, proteins cannot be characterized and listed using gene-expression analysis alone.