Qualitative and quantitative catalog of tyrosinase alternative transcripts in normal murine skin melanocytes as a basis for detecting melanoma-specific changes.
The decline in cell differentiation commonly associated with malignant progression may be due in part to an increase in alternative splicing of the pre-mRNAs of tissue-specific genes. As a necessary basis for investigating this possibility in a murine model of cutaneous melanoma, the complete qualitative and quantitative inventory of alternative transcripts was sought for the tyrosinase gene in normal mouse skin melanocytes, as this gene plays a key role in melanization. Of 111 alternative mRNAs predicted from known splice sites in the gene, 19 isoforms were detected, and their abundances determined, through a systematized protocol involving splice junction-specific probes, exon-specific restriction enzymes, and quantitative RT-PCR with an RNA internal standard. No unpredicted tyrosinase transcripts were discovered. Two of the transcripts, each involving an intra-exonic deletion and present at relatively low abundance in normal skin, were subsequently found to be consistently upregulated in melanomas.
Kelsall
S R
SR
Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111, USA.
Le Fur
N
N
Mintz
B
B
D017398:Alternative Splicing; D000818:Animals; D014408:Biomarkers, Tumor; D008544:Melanocytes / Q000201:enzymology* / Q000473:pathology; D008545:Melanoma / Q000201:enzymology*; D051379:Mice; D008810:Mice, Inbred C57BL; D014442:Monophenol Monooxygenase / Q000235:genetics*; D012867:Skin / Q000201:enzymology* / Q000473:pathology; D014158:Transcription, Genetic
D014408:Biomarkers, Tumor; D014442:Monophenol Monooxygenase