title: Sequence similarities of protein kinase substrates and inhibitors with immunoglobulins and model immunoglobulin homologue: cell adhesion molecule from the living fossil sponge Geodia cydonium. Mapping of coherent database similarities and implications for evolution of CDR1 and hypermutation.
abstract: Sequences of immunoglobulin (Ig) domains of adhesive molecule GSAMS from the living fossil sponge Geodia cydonium were compared with the important motif of peptide protein kinase substrates and inhibitors (PKSI), detail PKSI sequences, and a common template sequence, derived from structures determined previously. We found the site-restricted sequence similarities to these peptide sequences predominantly in the GSAM Ig1 domain of GSAMS in the domain region related to corresponding Ig similarities detected earlier. Additional sequence block-related analysis revealed the presence of CDR1-like segments within PKSI-related regions and resulted in the detection of increased numbers of hypermutation motifs just in the CDR1-like segment of GSAM Ig1 (GSAM(cdrl.1)). In the following database searches with PKSI-related regions and GSAM(cdr1.1) we looked for: (i) peptide similarities present in the context of Ig domains or related structures in a large range of species from Archaea to Vertebrata, and (ii) some special nucleotide similarities.
authors.affiliation: Center of Occupational Diseases, National Institute of Public Health, 100 42 Prague, Czechia. kubjar@szu.cz
authors.forename: J
authors.initials: J
authors.lastname: Kubrycht
authors.forename: J
authors.initials: J
authors.lastname: Borecký
authors.forename: P
authors.initials: P
authors.lastname: Soucek
authors.forename: P
authors.initials: P
authors.lastname: Jezek
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D005075:Biological Evolution; D015815:Cell Adhesion Molecules / Q000737:chemistry / Q000235:genetics*; D016208:Databases, Factual; D005580:Fossils; D007136:Immunoglobulins / Q000235:genetics / Q000378:metabolism*; D011161:Porifera / Q000235:genetics*; D047428:Protein Kinase Inhibitors; D011494:Protein Kinases / Q000378:metabolism*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D027041:Somatic Hypermutation, Immunoglobulin
chemical_list: D000596:Amino Acids; D015815:Cell Adhesion Molecules; D007136:Immunoglobulins; D047428:Protein Kinase Inhibitors; D011494:Protein Kinases