Amelogenins, cell adhesion proteins, play a role in the biomineralisation of teeth; They seem to regulate formation of crystallites during the secretory stage of tooth enamel development and are thought to play a major role in the structural organisation and mineralisation of developing enamel. The extracellular matrix of the developing enamel comprises two major classes of protein: the hydrophobic amelogenins and the acidic enamelins. Circular dichroism studies of porcine amelogenin have shown that the protein consists of 3 discrete folding units: the N-terminal region appears to contain beta-strand structures, while the C-terminal region displays characteristics of a random coil conformation. Subsequent studies on the bovine protein have indicated the amelogenin structure to contain a repetitive beta-turn segment and a "beta-spiral" between Gln112 and Leu138, which sequester a (Pro, Leu, Gln) rich region. The beta-spiral offers a probable site for interactions with Ca2+ ions. Muatations in the human amelogenin gene (AMGX) cause X-linked hypoplastic amelogenesis imperfecta, a disease characterised by defective enamel. A 9bp deletion in exon 2 of AMGX results in the loss of codons for Ile5, Leu6, Phe7 and Ala8, and replacement by a new threonine codon, disrupting the 16-residue (Met1-Ala16) amelogenin signal peptide.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71998022      1 MSNPYQQRGpslYAPPGPPVMHQngppgVVPTSNPYYQPPVPPQHHH---------MQPQAPMMS-PGMHG----QQQQ- 65
Cdd:smart00818  19 IRHPYPSYG---YEPMGGWLHHQ-----IIPVSQQHPPTHTLQPHHHipvlpaqqpVVPQQPLMPvPGQHSmtptQHHQp 90

                           90       100       110
                   ....*....|....*....|....*....|..
gi 71998022     66 ---QPYYNTQSPLTGTPPSMSYGTPQIPAPPP 94
Cdd:smart00818  91 nlpQPAQQPFQPQPLQPPQPQQPMQPQPPVHP 122

Amelogenins, cell adhesion proteins, play a role in the biomineralisation of teeth; They seem to regulate formation of crystallites during the secretory stage of tooth enamel development and are thought to play a major role in the structural organisation and mineralisation of developing enamel. The extracellular matrix of the developing enamel comprises two major classes of protein: the hydrophobic amelogenins and the acidic enamelins. Circular dichroism studies of porcine amelogenin have shown that the protein consists of 3 discrete folding units: the N-terminal region appears to contain beta-strand structures, while the C-terminal region displays characteristics of a random coil conformation. Subsequent studies on the bovine protein have indicated the amelogenin structure to contain a repetitive beta-turn segment and a "beta-spiral" between Gln112 and Leu138, which sequester a (Pro, Leu, Gln) rich region. The beta-spiral offers a probable site for interactions with Ca2+ ions. Muatations in the human amelogenin gene (AMGX) cause X-linked hypoplastic amelogenesis imperfecta, a disease characterised by defective enamel. A 9bp deletion in exon 2 of AMGX results in the loss of codons for Ile5, Leu6, Phe7 and Ala8, and replacement by a new threonine codon, disrupting the 16-residue (Met1-Ala16) amelogenin signal peptide.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71998022      1 MSNPYQQRGpslYAPPGPPVMHQngppgVVPTSNPYYQPPVPPQHHH---------MQPQAPMMS-PGMHG----QQQQ- 65
Cdd:smart00818  19 IRHPYPSYG---YEPMGGWLHHQ-----IIPVSQQHPPTHTLQPHHHipvlpaqqpVVPQQPLMPvPGQHSmtptQHHQp 90

                           90       100       110
                   ....*....|....*....|....*....|..
gi 71998022     66 ---QPYYNTQSPLTGTPPSMSYGTPQIPAPPP 94
Cdd:smart00818  91 nlpQPAQQPFQPQPLQPPQPQQPMQPQPPVHP 122

Amelogenins, cell adhesion proteins, play a role in the biomineralisation of teeth; They seem to regulate formation of crystallites during the secretory stage of tooth enamel development and are thought to play a major role in the structural organisation and mineralisation of developing enamel. The extracellular matrix of the developing enamel comprises two major classes of protein: the hydrophobic amelogenins and the acidic enamelins. Circular dichroism studies of porcine amelogenin have shown that the protein consists of 3 discrete folding units: the N-terminal region appears to contain beta-strand structures, while the C-terminal region displays characteristics of a random coil conformation. Subsequent studies on the bovine protein have indicated the amelogenin structure to contain a repetitive beta-turn segment and a "beta-spiral" between Gln112 and Leu138, which sequester a (Pro, Leu, Gln) rich region. The beta-spiral offers a probable site for interactions with Ca2+ ions. Muatations in the human amelogenin gene (AMGX) cause X-linked hypoplastic amelogenesis imperfecta, a disease characterised by defective enamel. A 9bp deletion in exon 2 of AMGX results in the loss of codons for Ile5, Leu6, Phe7 and Ala8, and replacement by a new threonine codon, disrupting the 16-residue (Met1-Ala16) amelogenin signal peptide.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 71998022      1 MSNPYQQRGpslYAPPGPPVMHQngppgVVPTSNPYYQPPVPPQHHH---------MQPQAPMMS-PGMHG----QQQQ- 65
Cdd:smart00818  19 IRHPYPSYG---YEPMGGWLHHQ-----IIPVSQQHPPTHTLQPHHHipvlpaqqpVVPQQPLMPvPGQHSmtptQHHQp 90

                           90       100       110
                   ....*....|....*....|....*....|..
gi 71998022     66 ---QPYYNTQSPLTGTPPSMSYGTPQIPAPPP 94
Cdd:smart00818  91 nlpQPAQQPFQPQPLQPPQPQQPMQPQPPVHP 122