Thymine nucleotides are not synthesized directly by cells but indirectly from other pyrimidine deoxyribonucleotides.Which of these statements is NOT correct regarding thymine nucleotide synthesis?
A)dUMP is the immediate precursor for dTMP.
B)The action of dUTPase allows dUTP to serve as a substrate in DNA synthesis.
C)The methyl donor in the reaction of dTMP is N5,N10-methylene-THF.
D)THF is used as a cofactor.

Question

Quizplus · Accepted Answer

dUTP is not used as a substrate in DNA synthesis due to the risk of uracil incorporation into DNA. The action of dUTPase is to convert dUTP to dUMP, which is then recycled back into the synthesis pathway for dTMP.

Thymine Nucleotides Are Not Synthesized Directly by Cells but Indirectly