Evaluation systems for individual sensitivity against ultraviolet light using one hair alone

点击翻译按钮获取中文摘要

This project has been intended to devise system that can monitor individual UV sensitivity by measuring transcriptional expression of tyrosinase or repair genes, which is known to defend from the deleterious effects of UV radiation.1) The 5' upstream regulatory region of the mouse tyrosinase gene contains a long (GA)n sequence, that may be capable adopting a triple-helical conformation (triplex). The results suggest that the 3'non-coding RNA fragments of mouse tyrosinase transcripts suppress its own expression at the transcriptional level. This might occur by preventing cell type-specific protein factor(s) from binding to the regulatory cis-elements in the 5' upstream region of the gene, possibly through a triplex formation.2) Tyrosinase is the key enzyme for synthesizing melanin pigments, which primarily determine mammalian skin coloration. We provide evidence that 5'flanking sequences from nonmammalian genes are functional in vivo by producing transgenic mice. 3) Microphthalmia-assoc … More iated transcription factor (MITF) plays a critical role in the development of both neural-crest-derived melanocytes and optic cup-derived retinal pigmented epithelium (RPE). We found that melanocyte development depends critically on a single Mitf isoform, Mitf-M. 4) We have established an in situ hybridization technique to investigate mRNA levels of pro-opiomelanocortin, tyrosinase, tyrosinase-related protein-1, dopachrome tautomerase, P-protein, Pmel-17/gp100, and microphthalmia-associated transcription factor. Results suggest that the mechanism of the tanning response of human skin may involve the transcriptional regulation of certain pigmentary genes. 5) Using an antibody to detect UV damage and anti-UvrA antibody, we measured the repair ability of recA strain of E. coli. Our results indicate that constitutive level of UvrA protein in the recA cells results in constitutive levels of active UvrABC nuclease which is not enough to operate full nucleotide excision repair (NER), thus leading to extreme UV sensitivity. Less