On the structure of functional sites in fibrinogen

Fibrinogen is involved in many biochemically and medically important processes. In order to obtain a deeper insight into the functional mechanisms of these processes it is necessary to analyse them on the molecular level. The complete covalent structure of human fibrinogen is known, and it is therefore now possible to establish structure-function relationships. For several functional sites the structural equivalent has been well identified, e.g. the thrombin and plasmin cleavage sites, the crosslinking site. For some other sites only the corresponding regions of the molecule are known, e.g. polymerization and calcium-binding sites. However, for many significant physiological functions of fibrinogen the structural basis has not yet been established. On the other hand, there are several regions of the molecule which by evolutionary evidence seem to be of functional importance, but for which no specific functions as yet have been assigned.