Gomez L A, Strasberg Rieber M, Rieber M
I.V.I.C., Tumor Cell Biology, Apartado 21827, Caracas 1020 A, Venezuela.
DNA Cell Biol. 1996 May;15(5):423-7. doi: 10.1089/dna.1996.15.423.
Characterization of genes expressed in normal cells and decreased in their malignant counterparts is important for detecting candidate tumor suppressor genes. We have now used comparative differential display of MRNAs from B16 melanoma and matched syngeneic normal melanocytes to detect a G0A gene expressed preferentially in resting G0 melanocytes compared to proliferating cells. Cloning and sequencing revealed no homology of G0A in the GenBank Database, suggesting that this is a new gene. Northern blot analysis with the cloned probe, confirmed about a five-fold higher expression in normal melanocytes compared to melanoma. Up-regulation of this gene was not detected by L-tyrosine induction of B16 melanoma terminal differentiation, but was seen in these cells, when exposed to the radiation sensitizer bromodeoxyuridine and subsequent UV radiation. Our differential expression data suggest that the G0A gene is important for melanocytic growth control and for the response of melanoma cells to radiation sensitizers.
鉴定在正常细胞中表达而在其恶性对应细胞中表达减少的基因对于检测候选肿瘤抑制基因很重要。我们现在利用B16黑色素瘤与其同源正常黑素细胞的mRNA比较差异显示，来检测一个与增殖细胞相比在静止的G0黑素细胞中优先表达的G0A基因。克隆和测序显示G0A在GenBank数据库中无同源性，表明这是一个新基因。用克隆探针进行的Northern印迹分析证实，与黑色素瘤相比，正常黑素细胞中的表达约高五倍。B16黑色素瘤终末分化的L-酪氨酸诱导未检测到该基因的上调，但当这些细胞暴露于辐射增敏剂溴脱氧尿苷及随后的紫外线辐射时则可见上调。我们的差异表达数据表明，G0A基因对于黑素细胞生长控制以及黑色素瘤细胞对辐射增敏剂的反应很重要。
