Figure 4.

An example of a class diagram showing the interactions between the components of the TGF-beta receptor complex (GO:0007181) (grayed). Cellular components containing these gene products are also shown. Due to space constraints functions are named using their corresponding GO ids. The class diagram was also constructed with a descriptive function name [see 8]. The GOid reference list is: GO:0042803, protein homodimerization activity; GO:0005160, TGF beta receptor binding; GO:0046982, protein heterodimerization activity, GO:0050431, TGF beta binding, GO:0005524, ATP binding; GO:0016740, transferase activity, GO:0046332, Smad binding; GO:0042301, phosphate binding; GO:0003677, DNA binding.