Final answer:
Histone-binding enzymes are directed by chemical modifications on histones to orchestrate the condensation state of chromatin, subsequently affecting gene expression.
Step-by-step explanation:
The tissue-specific histone binding enzymes that catalyze each chemical modification are attracted to the sites where chemical tags, such as phosphate, methyl, or acetyl groups, indicate whether a chromosomal region should be open for transcription or closed. These chemical modifications do not change the DNA sequence but influence the charge of histone proteins, thereby affecting the tightness of DNA binding and the accessibility of genes for transcription. During processes like histone acetylation and methylation, enzymes such as histone acetyltransferases (HAT enzymes) and methyl transferases are recruited to modify histones, enabling chromatin remodeling and influencing gene expression.