From UPSC perspective, the following things are important :
Prelims level : DNA/RNA
Mains level : Not Much
The famous British scientist and virologist Rosalind Franklin is remembered across the world on her birth centenary who worked to construct the double-helix structure of DNA.
Try this PYQ from CSP 2019:
DNA/RNA has been an all-time favourite of UPSC!
Q.‘RNA interference (RNAi)’ technology has gained popularity in the last few years. Why?
- It is used in developing gene-silencing therapies.
- It can be used in developing therapies for the treatment of cancer.
- It can be used to develop hormone replacement therapies.
- It can be used to produce crop plants that are resistant to viral pathogens.
Select the correct answer using the code given below:
(a) 1, 2 and 4
(b) 2 and 3
(c) 1 and 3
(d) 1 and 4 only
Rosalind Franklin (1920-1958)
- She was an English chemist and X-ray crystallographer whose work was central to the understanding of the molecular structures of DNA (deoxyribonucleic acid), RNA (ribonucleic acid), viruses, coal, and graphite.
- Although her works on coal and viruses were appreciated in her lifetime, her contributions to the discovery of the structure of DNA were largely recognised posthumously.
- In 1952, Raymond Gosling, a graduate student at King’s College London, took a historic X-ray photograph under Franklin’s supervision.
- Photo 51, as it is called, demonstrates the now-familiar, double-helix structure of DNA.
Why is she remembered now?
- The world is currently gripped in a pandemic, and her pioneering research in virology provided a crucial early step in the search for cures, vaccinations and tests.
- During the Second World War, Franklin carried out research into coal and graphite that proved important for gas-masks, the PPE of that time.
- It is because of Franklin, her collaborators and successors, that today’s researchers are able to use tools such as DNA sequencing and X-ray crystallography to investigate viruses such as COVID-10.
- Deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA) are perhaps the most important molecules in cell biology, responsible for the storage and reading of genetic information that underpins all life.
- They are both linear polymers, consisting of sugars, phosphates and bases, but there are some key differences which separate the two.
- These distinctions enable the two molecules to work together and fulfil their essential roles.
- DNA encodes all genetic information and is the blueprint from which all biological life is created. And that’s only in the short-term.
- In the long-term, DNA is a storage device, a biological flash drive that allows the blueprint of life to be passed between generations.
- RNA functions as the reader that decodes this flash drive. This reading process is multi-step and there are specialized RNAs for each of these steps.
Three types of RNA
- Messenger RNA (mRNA) copies portions of genetic code; a process called transcription and transports these copies to ribosomes, which are the cellular factories that facilitate the production of proteins from this code.
- Transfer RNA (tRNA) is responsible for bringing amino acids, basic protein building blocks, to these protein factories, in response to the coded instructions introduced by the mRNA. This protein-building process is called translation.
- Finally, Ribosomal RNA (rRNA) is a component of the ribosome factory itself without which protein production would not occur.