RESUMO
Per genes encode components of the circadian clocks controlling metabolic and behavioural rhythms. The human Per1 cDNA, RIGUI, was previously isolated and mapped on chromosome 17p12 (Sun, Z.S., Albrecht, U., Zhuchenko, O., Bailey, J., Eichele, G., Lee, C.C., 1997. RIGUI, a putative mammalian orthologue of the Drosophila period gene. Cell 90, 1003-1011). We have now isolated the entire genomic locus containing the human Per1 gene, in a search for genes associated with CpG-rich sequences. The hPer1 gene spans 15kb of human genomic DNA and is composed of 23 exons, flanked by 5' and 3' regulatory regions. Comparison of the hPer1 genomic clone with the dbEST database revealed homologies with putative alternative transcripts. Functional mapping within the 5' CpG-rich regulatory region enabled us to locate the hPer1 promoter core in a 510bp-long sequence centred around a TATA box, which supports high levels of hPer1 transcription. A second regulatory region was formally identified in intron 1, which appears to exert a negative role in transcriptional control of hPer1. These regions may be differentially involved in tissue-specificity, and/or circadian regulation, of the human hPer1 gene transcription.
Assuntos
Genes/genética , Proteínas Nucleares/genética , Regiões Promotoras Genéticas/genética , Células 3T3 , Animais , Sequência de Bases , Proteínas de Ciclo Celular , Cloranfenicol O-Acetiltransferase/genética , Cloranfenicol O-Acetiltransferase/metabolismo , Mapeamento Cromossômico , Cromossomos Humanos Par 17/genética , Clonagem Molecular , DNA/química , DNA/genética , DNA/isolamento & purificação , Proteínas de Drosophila , Éxons , Humanos , Hibridização in Situ Fluorescente , Íntrons , Camundongos , Dados de Sequência Molecular , Proteínas Circadianas Period , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Análise de Sequência de DNA , Transcrição GênicaRESUMO
We describe the complete sequence, genomic organization, and FISH chromosome mapping of the human VAMP2. We identified a 7-kb clone, pISSHG2b3A, containing the entire structure of VAMP2. Previous studies performed by others identified a 5-kb clone, pVPC5-2, containing the incomplete VAMP2. The pVPC5-2 clone was partially sequenced and mapped to the broad region 17pter-->p12 by somatic cell hybridization. Our clone overlaps the pVPC5-2 clone and extends approximately 2 kb at the 3' end. In this study, we mapped this gene more precisely on 17p12 by FISH and we found a new polymorphic microsatellite, (GT)(7)CC(GT)(5), in exon V. This microsatellite, revealing three alleles with frequencies of 0.778, 0.139, and 0.083, might be useful for future linkage studies. Finally, we localized three previously known markers, stSG12859, TIGR-A002F11, and WIAF-1699 (alias stSG4044), in the 3' untranslated region of the gene.