Clathrin-associated adaptor proteins - putting it all together

Adaptors are multifunctional linker proteins that, as a coated vesicle assembles, tether the clathrin lattice to the underlying membrane bud site. Each adaptor is composed of four distinct protein submits, but how these assemble into the functional complex is not clear. Here, some features of the protein sequences are discussed in an attempt to develop a speculative, low-resolution structural model of possible subunit interactions.