What the histone code and how it is read?
The pattern of histone modifications, called the histone code, influences transitions between chromatin states and the regulation of transcriptional activity. Four recent papers describe how plant homeodomain (PHD) finger proteins read part of this code.
What is the gene code for histone?
The canonical histone genes (H2A, H2B, H3, and H4) are encoded in the genome by a gene cluster that is expressed exclusively during S-phase, the phase of DNA replication, to allow newly expressed histones to be incorporated into the newly replicated DNA.
What are histone code readers?
Plant homeodomain (PHD) finger proteins are involved in various developmental processes and stress responses. They recognize and bind to epigenetically modified histone H3 tail and function as histone code readers. Overexpression of each gene confers stress tolerance in soybean plants.
What writes the histone code?
It has been known for over 45 years now that histones can be post-translationally modified by specific enzymes that write a histone code by adding or removing a number of different chemical modifications, including acetyl, phosphoryl and methyl groups (Figure 2).
What are types of histones?
Their function is to package DNA into structural units called nucleosomes. Histones are the main proteins in chromatin. Chromatin is a combination of DNA and protein which makes up the contents of a cell nucleus. Because DNA wraps around histones, they also play a role in gene regulation.
What does H3K27 methylation do?
Histone proteins constitute the core component of the nucleosome, the basic unit of chromatin. Methylation of histone H3 on lysine 27 (H3K27) is frequently found in the heterochromatin and conceives a repressive marker that is linked with gene silencing.
What are histones Class 11?
Histones are alkaline (basic pH) proteins. They are found inside the nucleus of eukaryotic cells. Their purpose is to package DNA into structural units called nucleosomes. They are the main proteins in chromatin (a combination of DNA and protein), which makes up the contents of a cell nucleus.