2019/07/18

Histone database and human traits and characteristics

Histone database and human traits and characteristics

Epigenetic markers of histones are still a relatively recent discovery in science, but studies of their relevance to individual characteristics are beginning to be found. Histones are DNA packing proteins, a type of protein cylinders around which DNA is wrapped.

https://www.abcam.com/epigenetics/histone-modifications-a-guide?fbclid=IwAR0DbxbQfpx6skl-8pCalyNI6dYBdGDbv4_88Yp3j3lVfOvlVetanQxzzKI

Excerpt: "Histones pack and order DNA into structures known as nucleosomes so that it fits within a cell’s nucleus. Each nucleosome contains two subunits, both made of histones H2A, H2B, H3 and H4 – known as core histones – with the linker histone H1 acting as a stabilizer."
 

Histone subunits have a histone tail that can attach a broad combination of different types of epigenetic markers such as methylation, acetylation, phosphorylation, ubiquitination, sumoylation, etc.
 
Histone markers control many cellular events, particularly protein synthesis and production of different RNA molecules. Their main function is to control the transcription of DNA either by closing the chromatin tight so that the DNA sequences do not end up into transcription or by opening, thereby allowing the cell to read the DNA for transcription. The histone markers also control alternative splicing procedure, thus allowing the cell to produce up to tens of thousands of different proteins using the same DNA sequence as a template file. In addition to transcriptional regulation, the histone database controls post-translation. Serious science is constantly finding new, complex regulatory functions for histone markers.

Keywords: histone transcription regulation, alternative splicing histone, histone post-translational regulation

There are writers, readers, and erasers for the epigenetic markers of histones. Thus, the entire histone database is a fully dynamic information library, allowing organisms to adapt efficiently under changing conditions. Reversible histone modifications are just regulation of existing biological information. That's why epigenetic regulation has nothing to do with evolution. Turn the lights on and off, turn the lights on again, did evolution happen?

Serious science has found several regulatory functions for histone markers that control and regulate a number of individual characteristics. For example, cranial and skeletal morphology is regulated by deacetylation of certain histone markers. Similarly, human height. In the bee colony, deacetylation of histone markers controls whether the larvae develops into a workers or a queen. Histone markers affect sex determination. In men, the X chromosome must be suppressed to prevent feminine traits from becoming dominant. Epigenetic markers of histones are responsible for this task. Mouse hair coloration is a trait controlled by histone markers. Accurate transcription timing and regulation in embryo development is a process driven by histone markers, etc. Science is constantly finding new roles for histone markers. It already seems obvious that histone markers form a complex biological database that plays a decisive role in an organism's characteristics and health.

Because the characteristics of an individual are inherited, a serious scientist have to make a question: What mechanisms affect the inheritance of the epigenetic markers of histones? There's a lot of research about this. Writing, reading and erasing of histone markers is mediated by non-coding RNA molecules such as miRNAs, lncRNAs, piRNAs, siRNAs, rRNAs and tRNAs. So is it possible that similar mechanisms control the inheritance of histone markers during reproduction and embryo development? Yes. For example, human sperm contains tens of thousands of different non-coding RNA molecules that deliver epigenetic information to embryonic cells. 

Keywords: embryonic cell development histone non coding rna

Thus, evolution does not occur in epigenetic switching. Change in organisms is not based on random mutations and selection but accurately controlled readers, writers and erasers driven by signals from environment. Serious science has also found that when the nucleosome and DNA wrapped around histone open for transcription, the DNA is prone to genetic errors=mutations. Not all errors are repaired by the cell, so genetic degradation is a biological fact.