Question

What are the four main types of chromatin structure modification involved in gene expression?

Answer 1

The four main types of chromatin structure modification involved in gene expression are histone acetylation, histone methylation, histone phosphorylation, and DNA methylation.

Step-by-step explanation:

The four main types of chromatin structure modification involved in gene expression are:

1. Histone Acetylation: Acetylation of histone proteins near the amino end of histones H2B and H4 tends to unwind nucleosomes and open the underlying DNA for transcription.
2. Histone Methylation: Methylation of lysines or arginines of histones H3 and H4 can open DNA for transcription, while demethylation has the opposite effect.
3. Histone Phosphorylation: Phosphorylation of histone proteins can affect the accessibility of DNA for transcription.
4. DNA Methylation: It involves adding a methyl group to the DNA molecule, which tends to close chromatin and inhibit gene transcription.

These modifications alter the chromosomal structure, either opening or closing the chromatin and impacting gene expression.