Article

The lysozyme enhancer: Cell-specific activation of the chicken lysozyme gene by a far upstream DNA element

The EMBO Journal (Impact Factor: 10.43). 05/1986; 5(4):719-24.
Source: PubMed

ABSTRACT

The chicken lysozyme gene is constitutively expressed in macrophages and controlled by steroid hormones in the oviduct. We have investigated the influence of the 5' noncoding region of this gene on its cell-specific transcriptional activation. In transient transfection experiments we have identified a far-upstream cell-specific enhancer element 6.1 kb 5' to the transcriptional start site of the lysozyme gene. Transcription from the lysozyme gene promoter is induced by this element in a position- and orientation-independent manner in lysozyme-producing myeloid cells (HBCI), but not in non-producing chicken embryo fibroblasts (CEF-38). The enhancer region correlates with a DNase-hypersensitive chromatin site which is only detectable in cells of tissues in which the lysozyme gene is transcribed. We suggest that this far-upstream element is involved in the tissue-specific control of lysozyme gene activity.

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Available from: Manfred Theisen
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    • "hages, neutrophils, and eosinophilic granular cells in skin epidermis and intestine (Fletcher & White, 1976;Sveinbjørnsson et al., 1996). In higher vertebrates, lysozyme c is present in polymorphonuclear and mononuclear phagocytes, and in Paneth cells, which are specialized intestinal epithelial cells (Keshav et al., 1991;Dohrman et al., 1994).Theisen et al. (1986) andShort et al. (1996)reported that the chicken genome, like the human, has a single lysozyme c gene, which is highly expressed in the oviduct and macrophages.Nile et al. (2004)found that three lysozyme genes were expressed in the chicken small intestine by villous enterocytes to fulfil complimentary roles in protecting the intestine, lysoz"
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    • "Lee) Tel.: +82-42-821-5779 Fax: +82-42-825-9754 E-mail: junheon@cnu.ac.kr 2010년 10월 5일 투고 2010년 10월 29일 심사완료 2010년 12월 13일 게재확정 Theisen et al., 1986 "
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    ABSTRACT: Single nucleotide polymorphisms (SNPs) in chicken lysozyme (LYZ) gene were investigated in this study. The identification of SNPs in both exon and intron in LYZ gene has led to understanding of evolution for the domestic chicken populations. A total of 24 samples from two Korean native commercial chicken populations (CCPs) were used for the initial identification of SNPs by mixing three DNA samples for sequencing experiments. By comparing with red jungle fowl (RJF), two commercial chicken populations have 18 common polymorphisms. Between two commercial chicken populations, 15 polymorphisms were identified. Of the 33 polymorphisms identified, two indels (21 and 4 bp) were found. Whereas, only one polymorphism in exon 2 at the bp position 1426 was a non-synonymous substitution (p.Ala49Val), indicating the amino acid changes. The identified non-synonymous substitution (p.Ala49Val) is located close to the catalytic sites of the enzyme, which might affect its activity. In our investigation, the polymorphisms in LYZ gene can provide broad ideas for the variation of Korean native chicken populations from the ancestor of chicken breeds as well as the some biological functions of the LYZ gene.
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    • "Other HSP70/CAT plasmids contain the promoter region of the human HSP70 gene (Kaddurah-Daouk et al. 1987). pLYSCAT constructs contain the promoter region of the chicken lysozyme gene (Theisen et al. 1986). (534) A sequence to which v-myb protein binds in vitro (Biedenkapp et al. 1988). "
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