Sequence Similarity Network Reveals Common Ancestry of Multidomain Proteins
(A) A hypothetical genome with two chromosomes. (B) Both chromosomes are copied through duplication or speciation, resulting in two identical copies. (C) Following sequence divergence, similarity is only retained in coding regions. (D) Two instances of the orange domain are inserted in g2 and g3’, respectively. A yellow domain is inserted in g2’. (E) Conserved genomic context shows that genes g2 are g2’ are homologous genes, although they contain unrelated domains. Similarly, genes g2 and g3’ contain homologous domains, but are not homologous genes.