o(6)-methyldeoxyguanosine triphosphate

o(6)-Methyldeoxyguanosine triphosphate (o(6)-Me-dGTP) is a modified nucleotide that plays a crucial role in DNA replication and repair. It is formed when the guanine base in deoxyguanosine triphosphate (dGTP) is methylated at the O6 position. This modification is often introduced by alkylating agents, such as those found in tobacco smoke and certain industrial chemicals. o(6)-Me-dGTP is important for research because it can lead to mutations in DNA, as it mispairs with thymine during DNA replication, resulting in transitions from G:C to A:T base pairs. This can contribute to the development of cancer. o(6)-Me-dGTP is also a substrate for DNA repair enzymes, such as O(6)-methylguanine-DNA methyltransferase (MGMT). MGMT removes the methyl group from o(6)-Me-dGTP, preventing mutations. Understanding the role of o(6)-Me-dGTP in DNA replication, repair, and mutagenesis is crucial for developing new therapeutic strategies for cancer prevention and treatment.'