Cloning and Identification of Two Unique Genes Involved in UV Induced Apoptosis on Human Keratinocyte (HaCaT) Cell Line

Differential gene regulation during UVB induced apoptosis of human keratinocyte cell line (HaCaT) has been investigated. Rapid amplification of polymorphic DNA (RAPD)-PCR was done to identify novel/unique genes in the purified apoptotic and non-apoptotic populations. Two genes were identified and cloned in pGemT vector. One of these genes (apgene-1) was upregulated in UV induced apoptotic cells and in the non apoptotic cells exposed to UV. The other gene (apgene-2) was not detected in apoptotic cells but expressed in non-apoptotic/non necrotic cells that had been exposed to UV. The presence of apgene-1 mRNA was not detected in camptothecin induced apoptotic as well as non apoptotic cells. Apgene-2 was not detected in camptothecin induced apoptotic cells but expressed in non-apoptotic/non necrotic cells. This data indicates differential regulation of these two genes during UV and chemical induced apoptosis in human keratinocytes. Additionally, since apgene-2 was upregulated in the non necrotic/non apoptotic population could be involved in protection.