Tyrosinase promoter

Melanin biosynthesis in animals is a complex process starting with the L-tyrosine amino acid. In the first step, L-tyrosine is converted first into DOPA and then into dopaquinone, a process catalyzed by tyrosinase. In the biosynthesis of eumelanins, dopaquinone undergoes a cyclization to form dopachrome and subsequently a tau-tomerization into 5,6-dihydroxyindole-2-carboxylic acid (DHICA). DHICA is further oxidized to indole-5,6-quinone2-carboxylic acid, the precnrsor of DHICA eumelanins. Tyrosinase-related proteins TRP-2 and TRP-1, respectively, are responsible for the last two steps, and they are under the control of the tyrosinase promoter. 

Ponnazhagan and Kwon (1992) reported a putative tissue-specific ds-element (TE-1) located at-236 bp of the mouse tyrosinase promoter. They partially purified a TE-1 binding protein (approximately 49 kDa in size), but tissue specificity remains to be confirmed by a more detailed analysis. For the human tyrosinase promoter, Shibata et al. (1992) identified a 200-bp pigment cell-specific enhancer, located between -2.0 and -1.8 kb. A minimum core sequence of 39 bp was shown to be sufficient to confer the specific activity, although other regions (not identified so far) within the 200-bp fragment are required for more efficient expression in melanoma cells (Shibata et al., 1992). 

Kltippel, M Beermann.F., Ruppert, S., Schmid, E Hummler, E., and Schiitz, G. (1991). The mouse tyrosinase promoter is sufficient for expression in melanocytes and in the pigmented epithelium of the retina. Proc. Natl. Acad. Sci. USA 88 3777-3781. 

B. W. Hughes, A. H. Wells, Z. Bebok, V. K. Gadi, R. J. Garver, W. B. Parker, and E. J. Sorscher, Bystander killing of melanoma cells using the human tyrosinase promoter to express the Escherichia coli purine nucleoside phosphorylase gene, Cancer Res. 55 3339 (1995). 

Ulasov rV, Rivera AA, Nettelbeck DM, Rivera LB, Mathis JM, Sonabend AM et al. An oncolytic adenoviral vector carrying the tyrosinase promoter for glioma gene therapy. Int J OncollOOH 31 1177 1185. 

Palumbo A, d Ischia M, Prota G (1987) Tyrosinase Promoted Oxidation of 5,6-Dihydroxyindole-2-caiboxylic Add to Melanin. Isolation and Characterization of Oligomer Intermediates. Tetrahedron 43 4203... 

GanB, R., Schiitz, G., and Beermann, F. (1994a). The mouse tyrosinase gene promoter modulation by positive and negative regulatory elements. J. Biol. Chem. (in press). 

Tumor tissue has also been demonstrated to take up naked pDNA following direct intratumoral injection, but this ability may be dependent on tumor type and the pDNA construct. In an important study by Vile and Hart (1993), mice bearing subcutaneous (s.c.) B16F1 melanoma or Colo 26 colon carcinoma were injected intratumorally with naked P -gal pDNA or P -gal pDNA/calcium phosphate precipitates. The tumors were collected on days 2, 4, 6 and 10 after the pDNA intratumoral injection. A gradual increase in blue-staining cells was found in the transfected melanomas with 10-15% of the cells expressing /3-gal by day ten. In contrast, none of the colon carcinoma tumors was positive for /3-gal. One explanation for the lack of in vivo transfection of the colon carcinoma is that the /3-gal pDNA constmcts contained melanoma-specific promoters (tyrosinase and TRP promoters). This study demonstrated that using an appropriate promoter established tumors could take up and express naked pDNA. 

R. G. Vile, R. M. Diaz, N. Miller, S. Mitchell, A. Tuszyanski, and S. J. Russell, Tissue-specific gene expression from Mo-MLV retroviral vectors with hybrid LTRs containing the murine tyrosinase enhancer/promoter, Virology 214 307 (1995). 

Hyper Production System of Aspergillus Oryzae Glucoamylase in Submerged Culture under Tyrosinase-Encoding Gene (Melo) Promoter Control... 

Ishida, H., Matsumura, K., Hata, Y., Kawado, A., Siginami, K., Abe, Y., Imayasu, S., and Ichishima, E. (2001). Establishment of hyper-protein pruduction system in submerged Aspergillus oryzae culture under tyrosinase-encoding gene (melO) promoter control. Appl. Microbiol. Biotechnol., 57, 131-137. 

Our own work in the area of aerobic oxidations was inspired by the exquisite research performed on the structure and reactivity of the binuclear copper proteins (7), hemocyanin and tyrosinase, and by the seminal contribution of Riviere and Jallabert (8). These two authors have shown that the simple copper complex CuCl - Phen (Phen = 1,10-phenanthroline) promoted the aerobic oxidation of benzylic alcohols to the corresponding aromatic aldehydes and ketones (Fig. 2). 

The phenoloxidase enzymes (peroxidases, tyrosinases, and laccases) are known to occur extracellularly in soils (16,17), and have been considered to play a role in catalyzing the coupling of aromatic amines to humic substances (3). Peroxidases have been studied most extensively. They use hydrogen peroxide to promote the one electron oxidation of aromatic amines and of phenolic moieties within humic substances to form free radicals. (12,18). 

Manganese dioxides operate in a manner similar to the phenoloxidase enzymes by promoting the one electron oxidation of anilines and phenols with the concomitant reductive dissolution of the manganese dioxide (Mn IV) to soluble manganese (Mn II) (21). In their work with guaiacol and 4-chloroaniline, Simmons et al. (19) reported that peroxidase, laccase, tyrosinase, and manganese dioxide all catalyzed formation of the same five co-oligomers as initial reaction products. 

A crnde extract of sweet potato Ipomoea-batatas (L.) Lam.) was nsed as a source of phenol oxidases (polyphenoloxidase, tyrosinase, catecholoxidase, EC 1.14.18.1). The extract was directly placed in the carrier of a FIA system with UVD, to promote oxidation of phenolic compounds to o-quinones that condense to form melanin-like pigments with a strong absorption at 410 nm. The determination of phenols in industrial wastewaters showed good agreement with conventional methods (correlation coefficient 0.9954) LOD was 10 p,M, with RSD <2.7% (w = 6). Under optimal storage conditions the enzymatic activity did not vary for at least five months . 

Galibert MD, Yavuzer U, Dexter TJ, et al. Pax3 and regulation of the melanocyte-specific tyrosinase-related protein-1 promoter./ Biol Chem. 1999 274 26894-26900. 

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