Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.10.3.1 (tyrosinase)
 9,065 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Since our first report showing that the phenotype of tyrosinase-negative or type IA oculocutaneous albinism (OCA) is a consequence of a mutation in the tyrosinase gene (Tomita et al., Biochem. Biophys. Res. Commun., 164:990-996, 1989), a number of mutations were found in the tyrosinase gene of OCA patients. However, to establish the molecular basis of OCA in each patient, we must carry out several important experiments as summarized here. First, we should confirm that the cloned or amplified genomic DNA segments are not derived from the pseudogene or related gene. It should be noted that the putative tyrosinase pseudogene contains the sequence almost identical to exons 4 and 5, including their exon/intron boundaries of the authentic tyrosinase gene. Thus, the mutations, detected in exon 4 or 5 amplified from genomic DNA, must be carefully analyzed to exclude a possibility that the mutation is located in the pseudogene. Second, it is of significance to confirm the promoter activity of the patients' tyrosinase gene. Accordingly, we established the cell-free transcription system derived from melanoma cells where the cloned tyrosinase gene is faithfully transcribed. Finally, transient expression assay of mutant tyrosinase is invaluable to conclude that OCA phenotypes are associated with the mutant tyrosinase alleles. I also discuss the implications of a cluster of mutation sites in exon 1 coding for the amino-terminus of tyrosinase.
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PMID:Mutations of the tyrosinase gene in oculocutaneous albinism. 129 10

We have cloned and sequenced the putative human tyrosinase pseudogene, which shares more than 98% nucleotide homology with exon 4 and exon 5 of the human tyrosinase gene including their flanking introns. Because of such a high homology, both the tyrosinase gene and its pseudogene could be amplified from genomic DNA by polymerase chain reaction. The nucleotide sequences presented thus enable us to discriminate the tyrosinase gene from its related sequences and are invaluable for a gene diagnosis of oculocutaneous albinism.
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PMID:Nucleotide sequence of the putative human tyrosinase pseudogene. 190 58