Agrima Bhatt, Rajasthan University
Brief about Eukaryotic cell
Prokaryotic cells and eukaryotic cells share some commonalities in structures such as plasma membrane, cytoplasm, and ribosomes. However, eukaryotes precede their ancestor by having membrane-bound organelles, the membrane-bound nucleus also referred to as a “True nucleus” and rod-shaped chromosomes. The genetic material of a eukaryotic cell is bound into chromatin under a membrane layer which is made up of some repeating units known as the nucleosome.
A nucleosome consists of two things: Histone proteins and base pairs of DNA. There are a total of eight histone proteins and 146 base pairs of DNA. DNA is coiled tightly around the histone proteins and forms a nucleosome core, when researchers saw evidence of this under the electron microscope, they named it the “beads on a string” structure of chromatin. This nucleosomal core possesses a certain N-terminal tail which enables the structure for post-translational modification (PTM). Some common modifications are processes such as methylation, acetylation, phosphorylation, etc. These modifications are chiefly responsible for gene expression regulation which can translate into tumour progression or metastasis, autoimmune diseases, and other genetic disorders.
Yeast – Saccharomyces cerevisiae
Similar to eukaryotic cells, post-translational modification in budding yeast i.e., Saccharomyces cerevisiae can lead to damaging growth, sudden cell death, etc. This takes place due to changes in the histone protein due to different phenomena such as histone methylation.
Histone methylation phenomena is a type of reversible modification that can affect gene expressions but will not change any sequence of the genetic material. It is the addition of a methyl group via covalent bonds to the side chains made up of amino acids – lysine and arginine of the histone proteins. Additions of the group onto the side chains facilitate the transcription factors and regulatory proteins which further cascade into the alteration in downstream gene expression. Saccharomyces cerevisiae is an ideal eukaryotic organism to study such processes since histone methylation is quite simplified in comparison to other eukaryotic organisms.
Importance of epigenetic modifications
Decoding and investigation of epigenetic modifications in yeast are of great interest to researchers across the globe since they will help in gaining novel insights into epigenetic modifications in higher multicellular organisms.
The effect of histone methylation enzymes on the immune system is of great medical and pharmacological importance since it opens doors to wide scientific applications in the field of anticancer drug development. Budding yeast as an experimental model provides a great stage to study epigenetic gene regulations and can develop this research into novel future applications like antiparasitic drugs.
Prospects
Despite many studies and research ongoing, we have little knowledge as to how these enzymes function at specific target locations in the yeast chromatin and carry out alterations in the genome.
More investigation is required into these post-translational modifications to study how gene regulation associates with cell-signalling machinery. It will be exciting to understand more about how PTMs regulate the time and occurrence of histone methylation enzymes in yeast chromatin, as well as which intracellular and extracellular molecules activate the transmission of signals to the histone methylation network.
Also read: déjà vu : the study is now a legit science
Reference:
- Separovich, R. J., & Wilkins, M. R. (2021). Ready, SET, Go: Post-translational regulation of the histone lysine methylation network in budding yeast. Journal of Biological Chemistry, 0(0). https://doi.org/10.1016/j.jbc.2021.100939
About Author:
Agrima Bhatt is an undergraduate student studying BSc. Biotechnology in Jaipur, Rajasthan. She is a science and research enthusiast who also loves to write articles and short snippets.
Some of her published articles at BioXone are:
- https://bioxone.in/news/worldnews/molecular-mechanisms-underlying-virescent-mutation-in-cotton/
- https://bioxone.in/news/worldnews/multi-angle-projection-microscope-a-novel-imaging-technique/
- https://bioxone.in/news/worldnews/scientists-develop-novel-cholera-vaccine-from-rice-grains/
- https://bioxone.in/news/worldnews/ai-predicts-the-relation-between-viruses-and-mammals/
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