title: Structure and organization of four clustered genes that encode bombyxin, an insulin-related brain secretory peptide of the silkmoth Bombyx mori.
abstract: Four genes encoding bombyxin have been located in a 14-kilobase Bombyx genomic DNA segment. All of these genes encode preprobombyxin, the precursor molecule for bombyxin, with the domain organization of signal peptide/B chain/C peptide/A chain. Bombyxins are classified as family A or B according to their sequence homology. Two genes, each belonging to a different family, are closely apposed to form a pair with opposite orientation, presumably forming a regulatory unit for transcription. Genomic Southern blot hybridization suggested that there are many such gene pairs in the Bombyx genome. Differences between bombyxin genes and vertebrate insulin-family genes indicate that different mechanisms operate in the evolution of invertebrate and vertebrate insulin-family genes.
authors.affiliation: Biological Institute, Faculty of Science, Nagoya University, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Kawakami
authors.forename: M
authors.initials: M
authors.lastname: Iwami
authors.forename: H
authors.initials: H
authors.lastname: Nagasawa
authors.forename: A
authors.initials: A
authors.lastname: Suzuki
authors.forename: H
authors.initials: H
authors.lastname: Ishizaki
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D012831:Bombyx / Q000235:genetics*; D003001:Cloning, Molecular; D005796:Genes; D007301:Insect Hormones / Q000235:genetics*; D007328:Insulin / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family; D015345:Oligonucleotide Probes; D021382:Protein Sorting Signals / Q000235:genetics; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid
chemical_list: D007301:Insect Hormones; D007328:Insulin; D015345:Oligonucleotide Probes; D021382:Protein Sorting Signals; C009089:prothoracicotropic hormone