title: Structure, evolution, and regulation of a fast skeletal muscle troponin I gene.
abstract: The complete structure of a quail fast skeletal muscle troponin I gene was determined by nucleotide sequence comparison of troponin I genomic and cDNA sequences. This 4.5-kilobase troponin I gene has eight exons. The actin-binding domain of troponin I is encoded by a single exon, whereas the troponin C-binding domain is split into at least two exons. The exon organization of the fast troponin I gene suggests that gene conversion directs the nonrandom conservation of the carboxyl-terminal halves of troponin I isoforms and that the amino-terminal extension of the cardiac isoform originated by splice-junction sliding. Comparison of the structure of the troponin I gene with the structures of other contractile protein genes reveals homologous sequences in their 5' flanking regions and similar large introns that separate protein-coding exons from 5' nontranslated exons. These common structural features may function to coordinate the activation of contractile-protein genes during myogenesis.
mesh_terms: D000199:Actins / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D005075:Biological Evolution; D003001:Cloning, Molecular; D003370:Coturnix; D005786:Gene Expression Regulation; D005796:Genes; D024510:Muscle Development; D011061:Poly A / Q000235:genetics; D011401:Promoter Regions, Genetic; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic; D014336:Troponin / Q000235:genetics*; D019210:Troponin I
chemical_list: D000199:Actins; D014336:Troponin; D019210:Troponin I; D011061:Poly A