Question

. Indicate whether each of the following histone modifications is generally associated with active genes (A) or silenced genes (S). Your answer would be a four-letter string composed of letters A and S only, e.g. SSAS.

( ) H3 lysine 9 acetylation
( ) H3 serine 10 phosphorylation
( ) H3 lysine 4 trimethylation
( ) H3 lysine 9 trimethylation

Answer 1

H3 lysine 9 acetylation, H3 serine 10 phosphorylation, and H3 lysine 4 trimethylation are generally associated with active genes, while H3 lysine 9 trimethylation is generally associated with silenced genes. These histone modifications regulate gene expression by affecting the accessibility of DNA.

Step-by-step explanation:

The histone modifications mentioned in the question are generally associated with active or silenced genes. Here is the association for each modification:

1. H3 lysine 9 acetylation: Generally associated with active genes (A).
2. H3 serine 10 phosphorylation: Generally associated with active genes (A).
3. H3 lysine 4 trimethylation: Generally associated with active genes (A).
4. H3 lysine 9 trimethylation: Generally associated with silenced genes (S).

These histone modifications play a crucial role in regulating gene expression by determining the accessibility of DNA for transcription.