In some organisms, cytosine is methylated at carbon 5 of the pyrimidine ring after it is incorporated into DNA. If a 5-methyl cytosine molecule is then hydrolyzed, as described in Problem 28, what base will be generated?

Key Concepts

DNA Methylation

DNA methylation is a biochemical process involving the addition of a methyl group to the DNA molecule, typically at the 5-carbon position of cytosine residues. This modification can influence gene expression and is crucial for processes such as genomic imprinting and X-chromosome inactivation. Methylation patterns can be heritable and play a significant role in cellular differentiation and development.

Hydrolysis of Nucleotides

Hydrolysis of nucleotides refers to the chemical reaction where water is used to break down nucleotides into their constituent parts. In the context of DNA, hydrolysis can lead to the release of nitrogenous bases, sugars, and phosphate groups. When 5-methyl cytosine undergoes hydrolysis, it specifically results in the release of the base cytosine, which is essential for understanding the consequences of methylation.

Pyrimidine Bases

Pyrimidine bases are one of the two classes of nitrogenous bases found in nucleic acids, the other being purines. The pyrimidine family includes cytosine, thymine, and uracil. Understanding the structure and function of these bases is vital for comprehending DNA and RNA synthesis, as well as the implications of modifications like methylation on genetic information and expression.