And so this one, shown in Brown, binds until this section. And this protein acts as an adaptive protein. So this molecule itself doesn't actually activate anything, but rather what it does is it acts as an anchoring point. It allows the attachment of an important protein shown in two, that is known as the SOS protein. So in one we have the phosphorylated region of the EGF receptor. This section here acts as an anchor for and adapt the protein we call GRB Two.