RESUMEN
PURPOSE: A number of genes and their products are induced early or late following exposure of cells to ionizing radiation. These radiation-induced genes have various effects on irradiated cells and tissues. Suppression subtractive hybridization (SSH) based on PCR was used to identify the differentially expressed genes by radiation in cervix carcinoma cells. MATERIASL AND METHODS: Total RNA and poly (A)+ mRNA were isolated from irradiated and non-irradiated HeLa cells. Forward- and reverse-subtracted cDNA libraries were constructed using SSH. Eighty-eight clones of each were used to randomly select differentially expressed genes using reverse Northern blotting (dot blot analysis). Northern blotting was used to verify the screened genes. RESULTS: Of the 176 clones, 10 genes in the forward-subtracted library and 9 genes in the reverse-subtracted library were identified as differentially expressed radiation-induced genes by PCR-select differential screening. Three clones from the forward-subtracted library were confirmed by Northern blotting, and showed increased expression in a dose-dependent manner, including a telomerase catalytic subunit and sodium channel-like protein gene, and an ESTs (expressed sequence tags) gene. CONCLUSION: We identified differentially expressed radiation-induced genes with low-abundance genes with SSH, but further characterization of theses genes are necessary to clarify the biological functions of them.