In translation – when a protein is built from amino acid blocks – most proteins emerge well dressed, with neatly folded beta sheets and gleaming alpha helices. These proteins march proudly and purposefully into the cell. From their first moment of being, they single-mindedly pursue their function.
There are some proteins though, which require extra help. Unaided, they would emerge from the translation process with floppy polypeptide limbs and embarrassing dipole moments. This of course will not do, so what are known as chaperone proteins help these disorganized youngsters get ready.
“No honey, THAT tyrosine goes there and THAT alanine goes there. And my goodness, you don’t really expect to regulate metabolism if you don’t even have a disulfide bond to hold your beta sheets up!”
With the help of these chaperones, the bewildered newly-formed proteins are spiffed up shiny and set loose upon the cell with strident purpose.
Now, sometimes, very rarely … there is a mutation in a chaperone. She stumbles to the ribosome late for work, yells at the rigid actin filament she arrived from for “swaying too much,” then drunkenly begins to prepare youthful proteins for their role in the cell.
“Loosen up those hydrogen bonds, do you really think you’ll get any kinase activity if you’re that uptight? Oooh, and the ladies LOVE a charged residue… Hmm, what else… Screw it, you’re good.”
We scientists theorize that this is how some tumors and politicians come to be.