Question

In some viruses, the flow of information is in the reverse direction, that is, from RNA to DNA. Can you suggest a simple name to the process?

Answer 1

Hint: The transfer of genetic information in an organism takes place from DNA to RNA. This process is called transcription. But, viruses opted for other ways for the transfer of information which is in the reverse direction of the conventional way of transcription.

Step by step answer:
The schematic representation of the flow of genetic information from DNA to RNA and finally to proteins is known as ‘central dogma’. The information that is stored in DNA is transferred to RNA by a process called transcription. Proteins receive the encoded information from RNA by the process called translation.
It was believed that the flow of genetic information takes place in a one-way direction, but it was found that complementary DNA or cDNA, a type of DNA molecule, can be formed from RNA template. This cDNA molecule is specific to every RNA molecule. This process of formation of DNA from a RNA template is known as reverse transcription. The enzyme which facilitates the process of reverse transcription is called reverse transcriptase. The process occurs in the cytoplasm of the cell.

Note: The process of reverse transcription is exploited in studying gene expression and function. This is done through the technique of DNA microarray. Scientists use DNA microarrays to measure the levels of expression levels of large counts of genes at the same time. In the initial process of DNA microarray, the mRNA or messenger RNA of the organisms is isolated. Then using the process of reverse transcription, they are converted into fluorescent-labeled cDNA. This is done using fluorescent markers. The mRNA is denatured and the remaining cDNA strand is allowed to bind with complementary strands to form a double-stranded structure. These strands are further analyzed by the DNA chip to obtain results.