This expectation pervades evolutionary thinking, and shows up again and again to be wrong. This week, instead of the usual junk-DNA-turned-marvel, it is junk protein. Here is what the evolutionist had to say:
Here we have a molecule that serves an important role in how cells function and survive, but it contains these puzzling 'junk' sequences that don't seem to have any apparent purpose. Our work suggests that this disorder is really a way of creating flexibility, allowing the protein to function as a molecular switch, a process that is thought to go wrong in certain diseases.
Evolution has provided researchers with convenient modular structures, areas that are repeated over and over again to make up proteins, and so we tend to dismiss the interspersed disordered sequences that don't seem to have any definable structure. Here we show that the weak molecular interactions in a disorganized protein equence are essential in giving this protein its unique attributes.
Well it is good to see that evolution has been helping researchers by providing convenient modular structures. At least evolution does something right.