Editorial 1 : The bacteria that write new genes to cope with infections
Context
Amid the unprecedented challenges presented by the COVID-19 pandemic, a once obscure enzyme found itself in the spotlight: reverse transcriptase.
About
- As laboratories worldwide rushed to develop reliable diagnostic tests, techniques using the enzyme became the gold standard to detect the SARS-2 virus, and a cornerstone of molecular diagnostics.
- This remarkable enzyme not only facilitated rapid and accurate testing; along with another powerful approach — genome-sequencing — it also helped track the virus’s spread, paving the way for surveillance, better public healthcare, and vaccine development.
- In the vesicular stomatitis virus, a protein called RNA polymerase was involved in reverse-translating RNA to DNA.
A molecular biology revolution
- The discovery was transformative. The prevailing belief at the time was that in all living beings, hereditary information flowed only from DNA to RNA and from RNA to protein (a.k.a. the ‘Central Dogma’).
- The discoveries of Drs. Temin and Baltimore et al. showed information could flow the other way, too, with RNA giving ‘rise’ to DNA.
- The discovery’s impact was also immediate. The ability of cells to create DNA copies from RNA revolutionised research methods in molecular biology, where researchers could reverse-transcribe messenger RNAs to pieces of DNA, clone that DNA into bacterial vectors, and study the function of the corresponding genes.
- In diagnostics, clinicians used reverse transcriptase to convert RNA to DNA and thus estimate the amount of viral material in a given sample.
- This technique quickly found wide application and use in the study of RNA viruses, including hepatitis B and the human immunodeficiency virus (HIV).
- Indeed, the discovery of reverse transcriptase had a significant effect on the management and treatment of HIV infections, including Acquired Immunodeficiency Syndrome (AIDS), in the 1980s.
- A generation of antiviral agents that specifically targeted the reverse transcriptase enzyme helped convert an otherwise deadly disease to one that could be managed, translating to improving the long-term outcomes and survival of people living with AIDS.
- Subsequent studies of the reverse transcriptase enzyme since the 1970s led to mechanistic insights into how viruses use this enzyme to replicate, as well.
Retroelements in the human genome
- Reverse transcriptases also had a significant role in shaping the human genome.
- The human genome is interspersed in many places with sequences, called elements, that appear to have originated from retroviruses. Thus, researchers call them retroelements.
- Evolutionary biologists believe these retroelements to have been transferred horizontally during the course of millions of years of evolution.
- Horizontal gene transfer refers to genes ‘jumping’ between organisms rather than from parent to offspring.
- And until recently, researchers also considered them to be “junk” elements: they were repeated through the genome and they seemingly did not confer any function to the human organism.
- However, recent evidence has suggested that these retroelements could really have had a profound impact on human biology and evolution, and that they play important roles in a variety of physiological processes.
- In a recent paper in the journal Nature Communications, researchers extensively studied the expression of genes in different parts of the human brain from post-mortem brain samples.
- They reported that the expression of more than a thousand human endogenous retroviruses — a major class of retroelements in the human genome — could be associated with a risk of neuropsychiatric diseases in humans.
- Retroelements in the human genome and bacterial reverse transcriptases have a common evolutionary history as well as share functional mechanisms.
- Bacterial reverse transcriptases — believed to be the precursors of their eukaryotic counterparts — exhibit analogous mechanisms.
- The discovery of reverse transcriptase activity across the different domains of life underscores the enzyme’s fundamental role in both prokaryotic and eukaryotic systems as well as a remarkable evolutionary continuity and functional versatility.
How do Klebsiella create genes?
- Researchers widely believed that bacterial reverse transcriptases were the precursors of their eukaryotic counterparts.
- In bacteria, as in the case of humans, retroelements are categorised as belonging to three broad groups: the Group II introns, the retrons, and the diversity generating retroelements.
- Klebsiella pneumoniae when infected by bacteriophages — viruses that infect bacteria — they use a non-coding RNA with specific motifs (or structures) that could bind to reverse transcriptase and instruct cells to create DNA. This DNA copy has multiple copies of a gene that can create a specific protein.
- The researchers dubbed this protein ‘Neo’ for “never-ending open-reading frame”.
- It could place the bacterial cell in a state of suspended animation, blocking its replication, and thus stalling the replication of the invading bacteriophage as well. Thus, the infection is stopped in its tracks.
Way forward
- Recent discoveries — including the role of reverse transcriptase in bacterial defence against bacteriophages — hint at the potential of innovative applications in biotechnology and medicine, especially in the context of emerging antimicrobial resistance, the ability of disease-causing microbes to resist the effects of substances designed to incapacitate or kill them.
- Further exploring reverse transcriptases could also reveal novel mechanisms of genetic evolution and viral resistance, potentially leading to new therapeutic strategies and biotechnological tools.
Editorial 2 : People at the centre
Context
The BJP needs to be more constructive, inclusive in approach to nation building. People are, and should be, at the centre of a democracy.
Nation building
- Nation building is a multifaceted process that requires the active involvement and collaboration of all segments of society.
- As a new government takes office, it is imperative to adopt constructive and inclusive approaches to ensure the holistic development and prosperity of the nation.
- The majority government’s policies and rhetoric have sometimes exacerbated social divisions along religious and caste lines as per critics.
- There have been periods of economic slowdown during the tenure of the BJP government, which have led to concerns about job creation, investment, and overall economic growth.
- The government’s handling of farmers’ protests, particularly in relation to agricultural reforms, has been a subject of controversy. Critics argue that the reforms have favored corporate interests over the welfare of farmers, leading to widespread protests and calls for repeal of the laws.
- Environmental issues and climate change have also been areas of concern, with critics pointing to policies that prioritize economic development over environmental conservation. This has led to debates over issues such as deforestation, air pollution, and climate adaptation.
Suggestions
- Creating policies and initiatives that promote cultural exchange, understanding, and harmony among different communities.
- Ensuring representation of various ethnic, religious, and linguistic groups in decision-making bodies and government institutions.
- Investing in education infrastructure and resources to provide quality education for all, irrespective of socio-economic background
- Promoting inclusive curricula that reflect the diversity of the nation and incorporate values of tolerance, empathy, and respect for others.
- Implementing policies that address income inequality and provide opportunities for economic empowerment for marginalized communities.
- Supporting small and medium-sized enterprises (SMEs) owned by minorities, women, and disadvantaged groups through financial assistance, training, and mentorship programs.
- Strengthening legal frameworks to protect the rights of all citizens, including minorities, women, LGBTQ+ individuals, and persons with disabilities.
- Combating discrimination and prejudice through awareness campaigns, anti-discrimination laws, and punitive measures against perpetrators of hate crimes.
- Fostering partnerships with civil society organizations, grassroots movements, and community leaders to facilitate participatory decision-making and implementation of policies.
- Developing infrastructure projects that benefit all regions and communities, bridging urban-rural divides and reducing disparities in access to basic services such as healthcare, transportation, and sanitation.
Conclusion
India has once again proved to itself and the world that it is a vibrant, functioning democracy. The new government has a responsibility to live up to the expectations of the people, and they are much more than a voter base.
