Histones Are Quotes & Sayings

In this model, there is a vicious cycle of events that results in the generation of a more and more repressed state. One of the predictions from this model is that repressive histone modifications attract DNA methyltransferases, which deposit DNA methylation near those histones. This methylation in turn attracts more repressive histone modifying enzymes, creating a self-perpetuating cycle that leads to an increasingly hostile region for gene expression. Experimental data suggest that in many cases this model seems to be right. Repressive histone modifications can act as the bait to attract DNA methylation to the promoter of a tumour suppressor gene. A key example of this is an epigenetic enzyme we met in the previous chapter, called EZH2. The EZH2 protein adds methyl groups to the lysine amino acid at position 27 on histone H3. This amino acid is known as H3K27. K is the single letter code for lysine (L is the code for a different amino acid called leucine). — Nessa Carey

I wish I could claim I faced my first day of apostasy with courage and certainty. Yet in truth, I had never felt more afraid. — David Ebershoff

The professor at the boxing gymnasium wore mustaches and was very precise and jerky and went all to pieces if you started after him. — Ernest Hemingway,

And of course I didn't know who would marry me now that I'd been where I had been. I didn't know at all. — Sylvia Plath

So they put the gold in bags and slung them on the ponies, who were not at all pleased about it. — Brandon Sanderson

There is increasing evidence that at least some of the targeting of epigenetic modifications can be explained by interactions with long ncRNAs. Jeannie Lee and her colleagues have recently investigated long ncRNAs that bind to a complex of proteins. The complex is called PRC2 and it generates repressive modifications on histones. PRC2 contains a number of proteins, and the one that interacts with the long ncRNAs is probably EZH2. The researchers found that the PRC2 complex bound to literally thousands of different long ncRNA molecules in embryonic stem cells from mice13. These long ncRNAs may act as bait. They can stay tethered to the specific region of the genome where they are produced, and then attract repressive enzymes to shut off gene expression. This happens because the repressive enzyme complexes contain proteins like EZH2 that are capable of binding to RNA. — Nessa Carey

The Doctor: You know how adults tell you everything's going to be fine, just to make you feel better?
Amelia: Yes.
Doctor: Well ... everything's going to be fine. — Steven Moffat