An overlap between a network cluster that was obtained by the Potts algorithm  and the best matching GO groups from the molecular function GOA. The cluster contains eight proteins: five heterodimerizing proteins from the ionotropic glutamate receptor family, syndecan binding protein SDCBP, gamma subunit 2 of voltage-dependent calcium channel (CACNG2), and protein kinase C alpha binding protein (PRKCABP). The molecular function GOA shows the smallest correlation with network clustering among all GOAs (see Results section for details). Nevertheless, the correlation is still significant and provides additional confirmation to the observation that paralogous proteins tend to interact with each other more often than non-paralogous proteins . The picture shows the example of the paralog heterodimerization that form a cluster in the physical interaction network. A – The portion of GO classification overlapping with network cluster. The GO classification tree depiction is the same as in Figure 5A. B – The network cluster overlapping with GO classification from Figure A. Highlighted proteins belong to the best overlapping GO group from molecular function classification – alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionate selective glutamate receptor activity (GO: 0004971). The proteins selected by the blue line belong to the second best overlapping GO group from molecular function classification – potassium channel activity (GO:0005267). Gray links indicate DirectRegulation relation, violet links indicate Binding relation.