Skip to main content

DNA Methylation

We are all aware that every cell in the body has a different function. The eye cells allow us to see this wonderful planet, the stomach cells help us to digest the delicious meals, and the brain cells allow us to think through hard problems or situations. This list is super long. Have you ever wondered why our eye cells never secret hydrochloric acid just like the stomach cells? Why can’t we see with our nerve cells? Every cell is differentiated, but how? A part of the answer is DNA methylation. Now let us discuss the process of DNA methylation in detail. 

What is DNA methylation?

DNA methylation is an epigenetic1 mechanism to silence the genes from transcribing to RNA. Research on DNA methylation suggests that the cytosine bases are methylated to ensure that the genes are in the “locked” mode. The DNA methyltransferase enzyme converts the cytosine base to 5-Methylcytosine which aids to silence the gene (2). This process is essential to inactivate one X-chromosome2 in the girls. Therefore, this ensures that both the sexes have one active X chromosome. We can also safely conclude that DNA methylation is a crucial process for cell differentiation. To answer the questions mentioned in the introduction, DNA methylation plays a role in why we can’t see through our nerve cells or why our eye cells do not secrete hydrochloric acid. We should express our gratitude as we have avoided a major pathology caused by the acid secretion in the eyes! 

DNA methylation and cancer

Cancer is a genetic disorder that causes uncontrollable cell growth which has the potential to cause numerous problems. The scientists have noticed some abnormal DNA methylation patterns in cancer patients. With that being said, many researchers have concluded that there might be an inverse relationship between gene expression and DNA methylation levels in the cancer cells. Also, the common pattern observed in cancer cells is the extensive hypomethylation of the genes. It means that the traditionally silent protooncogenes3 are activated after these alterations. If these genes are not methylated, it means they have been activated. Moreover, the genes that are traditionally active to suppress any unchecked cell growth, are observed to be methylated in the cancer cells (3). It means that the suppression of the tumor suppressor genes and the activation of the protooncogenes might be a cause for the development of cancer. 

Conclusion:

DNA Methylation is an excellent epigenetic signaling tool that is very crucial for the development of a human being. This technique plays a huge role in cell differentiation and also inactivates the X chromosome in females. However, this technique can be a source for the development of cancer, and hence with research, we can better understand the role of DNA methylation in cancer. 

Notes:

  1. The inherited phenotypic changes which are not involved in the alteration in the DNA sequence 
  2. The inactivated X body is referred to as the Barr body 
  3. When this gene is mutated, then it can be converted to an oncogene, which leads to cancer 

 

Works Cited:

  1. Jin, B., Li, Y., & Robertson, K. D. (2011). DNA Methylation: Superior or Subordinate in the Epigenetic Hierarchy? Genes & Cancer, 2(6), 607–617. https://doi.org/10.1177/1947601910393957
  2. Shiel, W. C. (2017, January 25). Medical Definition of Proto-oncogene. MedicineNet; MedicineNet. https://www.medicinenet.com/script/main/art.asp?articlekey=5088
  3. The Role of Methylation in Gene Expression | Learn Science at Scitable. (2014). Nature.Com. https://www.nature.com/scitable/topicpage/the-role-of-methylation-in-gene-expression-1070/
  4. Wajed, S. A., Laird, P. W., & DeMeester, T. R. (2001). DNA Methylation: An Alternative Pathway to Cancer. Annals of Surgery, 234(1), 10–20. https://doi.org/10.1097/00000658-200107000-00003



Comments

Post a Comment

Popular posts from this blog

GPCR signaling and its importance as a pharmacological target

  Introduction There are several important concepts in biochemistry that explain how certain things work in our bodies. Of these, cellular communication is a crucial topic to discuss. Through the elegance of this complex process, our body is able to establish communication routes to produce a desired outcome. Have you ever wondered how you know you are hungry? Or how do your hands quickly move away if you accidentally touch something extremely hot? Your body has its own USPS system that serves to establish communication channels to respond to various environmental stimuli.  One such important cellular communication platform is the GPCR signaling or the G-protein coupled receptors. These receptors are highly expressed in the human genome and are responsible for signal transduction in various metabolic pathways. 1 Hence, serving as a major pharmacological target to treat numerous metabolic diseases.  In this blog, I am going to discuss the basics of GPCRs mediated signal transduct
Post a Comment
Read more

Metabolomics: an innovative link between biochemistry and nutritional sciences

  Biochemically, metabolism is defined as the overall reactions occurring in the living body. Metabolic reactions can be divided into categories, 1) anabolic, and 2) catabolic. In humans, common catabolic reactions are involved in the digestion of consumed food products.  These catabolic pathways include glycolysis, the citric acid cycle, the urea cycle, fatty oxidation, etc. These reactions are involved in the metabolism of carbs, proteins, and fats. All the aforementioned reactions produce metabolites (or intermediates) as a part of metabolizing the macronutrients. The produced metabolites could be indicative of the metabolic health of a person. Similarly, the alteration of this metabolite production can signify disease development. New research studies are involved in the analysis of such metabolites which serves as a breakthrough in the field of personalized medicine. Section 1. Metabolic pathways and metabolites In this section, I am going to discuss some metabolic reaction
Post a Comment
Read more

The Potential of CRISPR

  Abstract: The newly developed technique, CRISPR, or Clustered Regularly Interspaced Short Palindromic Repeats, is based on the bacterial “immune system”. CRISPR-Cas9 system was discovered in the 1970s in the E.Coli bacteria. This system is naturally found in the bacteria as an anti-infection mechanism. If an analogy is to be drawn, the CRISPR-Cas9 system can be compared to the antibodies in humans. When the bacteria sense a viral invasion, it targets the viral DNA and creates strands of this targeted DNA. These fragments are known as the “CRISPR fragments” and are stored as a memory when there is an invasion by the same virus. If there is an invasion by the same virus, the CRISPR fragments produce RNA which later targets the viral DNA. The Cas9 enzyme functions to destroy the viral DNA. Similarly, in the lab, a biologist can target a specific sequence of the gene and use the CRISPR “scissors” to cut the DNA at a specific site. Scientists aim to apply this technique for cancer cures
Post a Comment
Read more