title: Structure and expression of the Aplysia californica calmodulin gene.
abstract: We have isolated and characterized the calmodulin (CaM) gene of the marine mollusc Aplysia californica. Its primary structure, deduced from the nucleotide sequence of the gene, is highly conserved, containing only three amino acid substitutions compared to the CaM of higher vertebrates. The structural gene consists of four exons that encode the protein, 3' non-translated mRNA and at least one additional exon encoding 5' non-translated mRNA and the initiator methionine. A comparison of the exon/intron structure of CaM genes from several organisms shows conservation of intron position, suggesting that introns have been both inserted and deleted during evolution. Northern analysis of RNA prepared from several Aplysia tissues reveals the presence of several CaM mRNA transcripts with the greatest expression observed in neural and muscle tissue. One of these transcripts is abundant only in mRNA prepared from nervous tissue.
authors: Howard Hughes Medical Institute, Center for Neurobiology and Behavior, Columbia University, New York, NY 10032.
authors: M E
authors: ME
authors: Swanson
authors: S F
authors: SF
authors: Sturner
authors: J H
authors: JH
authors: Schwartz
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001048:Aplysia / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D015152:Blotting, Northern; D002147:Calmodulin / Q000096:biosynthesis / Q000235:genetics*; D003001:Cloning, Molecular; D015342:DNA Probes; D005091:Exons / Q000235:genetics; D005724:Ganglia / Q000378:metabolism; D008969:Molecular Sequence Data; D009417:Nerve Tissue / Q000378:metabolism; D009928:Organ Specificity; D010446:Peptide Fragments / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D002147:Calmodulin; D015342:DNA Probes; D010446:Peptide Fragments; D012333:RNA, Messenger