Characteristic sequences in the promoter region of the chicken tyrosinase-encoding gene.
We have isolated and sequenced a genomic DNA sequence encoding chicken tyrosinase (TYR) that includes 2125 nt of 5' flanking sequence, the first exon and a part of the first intron. The 5' flanking sequence was able to drive transcription of a reporter gene in immortalised quail neural crest cells. The sequence, which is the most extensive to be reported for a lower vertebrate TYR gene to date, was further analyzed using primer extension and computer-aided homology searches. Transcription initiation appears to occur at heterogeneous start points and in the absence of a TATA box, but may be mediated via a potential initiator (Inr) element and Sp1-binding motif. We have identified two evolutionarily conserved regions within the 5' flanking sequence that may be functionally significant, as they contain regulatory elements previously reported to play a role in melanocyte-specific expression of TYR in mammals. This study contributes towards an understanding of the requirements for melanocyte-specific TYR expression in lower vertebrates.
Ferguson
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Department of Anatomy and Cell Biology, University of Cape Town Medical School, Observatory, South Africa.
Kidson
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D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002645:Chickens; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D008969:Molecular Sequence Data; D014442:Monophenol Monooxygenase / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics*
D004247:DNA; D014442:Monophenol Monooxygenase