Basics of The RNA You Need to Understand

What will you learn? show

At a Glance of RNA

In this blog, We are discussing RNA. Read my Previous blogs also so that you will never miss the detail.

 

RNA and DNA are the genetic material discussed in Alfred Hershey and Martha Chase’s confirmatory experiment in the previous blog. Deoxyribose nucleic acid (DNA) is responsible for transferring genetic information from parent to child. Now the question about RNA is

  • What is first (DNA or RNA)?
  • What is the location of DNA and RNA?

These and so many other questions like this arise after the confirmation of genetic material. If DNA is responsible for all the transfer of genetic information, then.

  • What is the role of RNA?
  • What are the unique facts about RNA? And
  • Why is DNA selected over RNA?

In the upcoming series of blogs, we will deal with all these questions and some basic processes. From earlier blogs, we can conclude one molecule’s basic properties to be a genetic molecule. Those properties are as follows.

  1. The molecule should be able to self-replicate.
  2. It must be chemically and structurally stable.
  3. The molecule should be able to follow the Mendelian cross.
  4. It should provide the scope for the mutation that is required for the evolution.

The reason behind the selection of DNA over RNA is the stability of DNA molecules over RNA. And the structural specification also plays an important role in this selection. The DNA stability is well described in the Griffiths transforming principle, which we have discussed in the previous article. According to Griffiths’s experiment, the two strands of DNA separated by heating comes together to form a stable structure again because of the complementary structure of DNA.

RNA Tour

Ribonucleic Acid is a linear single-stranded molecule composed of nucleotide sequence, same as DNA. The structural difference between DNA and RNA is the presence of uracil in the structure of RNA, unlike thymine in DNA. It also can show direct duplication.

One more property should genetic molecule possess is to be stable enough not to change with different life cycle stages, age, or change in physiology in the organism. One more major difference I would like to highlight is the presence of 3’-OH and 2’OH groups of the pentose sugar.

This basic difference of thymine and uracil is providing additional stability to the DNA. Suppose we want to focus more on the stability differences. In that case, the 2’OH group present at every nucleotide in RNA structure is reactive, making RNA labile and easily degradable. Hence RNA is catalytic and reactive.

In contrast, this 2’OH group is not present in DNA. And hence DNA is chemically less reactive and more stable. This fact is enough for the selection of DNA over RNA. Both RNA and DNA can mutate; rather, RNA can mutate faster than DNA.

This image will differentiate the structures of DNA and RNA
Structure of Pentose Sugar present in DNA and RNA

RNA performs both the role of catalyst and genetic material. Proteins catalyze not all biochemical reactions in living systems, but some are catalyzed by RNA also. Being a catalyst, RNA is more reactive and therefore more unstable. In a lifetime scenario, RNA has a short lifetime while DNA has a long one. DNA is an evolved and a modified form of RNA which is more stable than DNA.

Location and Working Differences of RNA and DNA

RNA only can directly code for the synthesis of different proteins. On the other hand, DNA is the genetic and hereditary material of the cell. DNA can present in the nucleus and mitochondria due to favorable conditions in contrast to that RNA that can present in both nucleus and cytoplasm.

Though DNA is evolved form of RNA, what do you think is the reason behind this? Firstly, stability reasons we can consider in addition to that, it is found that all the machinery required for the protein synthesis is revolved around the RNA.

Being more stable, DNA is preferred for the storage of genetic information. And RNA is responsible for the transmission of that genetic information through the process called translation. It is proved that genetic information flows from DNA to RNA through various processes that we will discuss in upcoming blogs.    

This image will give you the detailed flow of genetic information from DNA to RNA
The flow of Genetic Material

The flow of genetic information initiates from DNA, and the formation of mRNA takes place through transcription. Further, the transcribed genetic information results in the formation of protein through translation. This protein then acts as a signaling molecule for the further process.

What is first?

Before discovering the RNA molecule, the protein was considered the genetic material responsible for all the genetic events. Further after the discovery of RNA and various studies, experiments prove some facts. It includes something that has the property of folding and duplicate itself. Still, that molecule is must not protein because protein itself shows a folding pattern and dissociate after finishing target work.

So, scientists have proved that either RNA or RNA-like molecules can store genetic information and transmit it. Initially, scientists could not synthesis the same molecule in the laboratory. Further, they have discovered the RNA polymerase enzymes which affect the transcription processes. This theory of RNA is termed as “RNA world.”

All the experimental studies and the proofs confirm that RNA is the first genetic material discovered. And there are now many pieces of evidence suggesting that RNA is involved in many essential processes like metabolism, translation, splicing, etc.

RNA can be present in different forms like mRNA (messenger RNA), tRNA (Transfer RNA), rRNA (Ribosomal RNA). And its structure is hairpin and loop. DNA is present in nuclear form, and mitochondrial DNA with antiparallel helix look.  

After this introductory discussion about RNA, we will discuss all the types of RNA and DNA in detail. Also, we will look at the brief introduction about all the processes followed by RNA and DNA. Till the time stay connected with us.

Chronology

Subscribe our Newsletter

* indicates required

Intuit Mailchimp