Final answer:
Neutralizing the positive charge of histones through modifications like acetylation can lead to a relaxed chromatin structure and increased DNA accessibility. In the context of X chromosome inactivation in females, such changes can cause a tightly packed nucleosome structure and heterochromatin formation, rendering the chromosome inactive.
Step-by-step explanation:
Neutralizing the histone charges from positive to neutral would lead to a change in the interaction between DNA and histones, affecting the structure of chromatin. Histones are proteins that package and order DNA into structural units called nucleosomes, and they typically possess positive charges due to the presence of lysine and arginine amino acids. When positively charged, they can effectively bind to the negatively charged phosphodiester backbone of DNA. If the charge of histones is neutralized, for example through the addition of acetyl groups during the process of acetylation, this reduces their positive charge and decreases their affinity for DNA. This can result in a more relaxed chromatin structure, thereby increasing the accessibility of the DNA for transcription. In the specific context of X chromosome inactivation in females, epigenetic changes such as methylation of histones can contribute to the formation of heterochromatin, making the chromosome transcriptionally inactive and resulting in a tightly packed nucleosome structure.