How does chromatin affect gene expression?
Chromatin structure plays a key role in regulating gene expression by allowing DNA accessibility to transcriptional machinery and transcription factors .
How do chromatin modifications control gene expression?
Modifications in the globular domains of histones can directly affect transcription and nucleosome stability. … Overall, recent work has shown that histone core modifications can not only directly regulate transcription, but also influence processes such as DNA repair, replication, stemness, and changes in cell state.
What are the chemical modifications of the chromatin that can affect gene expression?
Rather, epigenetic modifications, or “tags,” such as DNA methylation and histone modification, alter DNA accessibility and chromatin structure, thereby regulating patterns of gene expression.
How are chromatin modifications passed down?
However, during DNA replication, the parental histone proteins are all removed from the DNA during the process of chromatin disassembly, and the chromatin is reassembled onto the two daughter DNA duplexes following DNA replication.
Does chromatin regulate gene expression?
In eukaryotes, the tight or loose packaging of the genes in chromatin (DNA plus specific proteins) can control whether the genes can be expressed to form their encoded product. DNA itself can be methylation and that also regulates gene expression, generally to turn off the gene. …
How methylation affects gene expression?
DNA methylation regulates gene expression by recruiting proteins involved in gene repression or by inhibiting the binding of transcription factor(s) to DNA. … As a consequence, differentiated cells develop a stable and unique DNA methylation pattern that regulates tissue-specific gene transcription.
Which of these is a type of post transcriptional regulation of gene expression?
In Summary: Post-TransCRIPTIONAL Control of Gene Expression
This involves the removal of introns that do not code for protein. … RNA stability is controlled by RNA-binding proteins (RPBs) and microRNAs (miRNAs). These RPBs and miRNAs bind to the 5′ UTR or the 3′ UTR of the RNA to increase or decrease RNA stability.
How do insulators affect gene expression?
1A). The second way in which insulators protect genes is by acting as “barriers” (Sun and Elgin 1999) that prevent the advance of nearby condensed chromatin that might otherwise silence expression. Some insulators are able to act both as enhancer blockers and barriers (Table1).
How does chronic stress change your DNA?
Telomeres are a protective casing at the end of a strand of DNA. Each time a cell divides, it loses a bit of its telomeres. An enzyme called telomerase can replenish it, but chronic stress and cortisol exposure decrease your supply. When the telomere is too diminished, the cell often dies or becomes pro-inflammatory.