Context:
Recent research has discovered a novel protein, referred to as “Neo,” which plays a critical role in bacterial defence mechanisms against viral infections, particularly bacteriophages.
Relevance:
GS III: Science and Technology
Dimensions of the Article:
- About Neo
- Reverse Transcriptase
About Neo
Discovery and Background
- Research Team: Led by Stephen Tang and Samuel Sternberg, reported in a 2023 preprint paper on bioRxiv, while studying Klebsiella pneumoniae.
- Bacterial Defense Mechanism: Bacteria defend against viral infections (bacteriophages) using diverse immune systems that sense and target foreign nucleic acids. One such system is the Defense-associated Reverse Transcriptase (DRT) system.
DRT-2 System Mechanism
- Gene Synthesis: In the DRT-2 system, bacteria undergo de novo gene synthesis via rolling-circle reverse transcription (RT) of non-coding RNA (ncRNA).
- Synthesis Process:
- Uninfected Bacterial Cells: ncRNA and RT enzyme lead to the synthesis of a repetitive single-stranded cDNA.
- Phage Presence: Triggers the second-strand cDNA synthesis, producing long double-stranded DNA.
- Function of cDNA: Generates messenger RNAs that encode a stop codon-less, never-ending open-reading frame (neo). The translation of the neo protein causes potent growth arrest (cell dormancy) in bacteria, protecting the population from phage spread.
Significance in Biotechnology and Medicine
- Potential Tool: Represents a potential biotechnological tool for controlling viral infections.
- Evolutionary Insights: Retroelements in the human genome and bacterial reverse transcriptases share a common evolutionary history and functional mechanisms.
- Precursors: Bacterial reverse transcriptases are believed to be precursors of their eukaryotic counterparts, exhibiting analogous mechanisms.
Reverse Transcriptase
- Function: Enables cells to create DNA copies from RNA, a process called reverse transcription, performed by the enzyme reverse transcriptase.
- Discovery: Discovered by Howard Temin and David Baltimore in 1970, revolutionizing molecular biology research methods.
Applications:
- Gene Cloning: Used in molecular biology to clone genes.
- PCR: Performs Polymerase Chain Reaction (PCR).
- Genome Analysis: Analyzes genomes.
- Diagnostics: Detects and quantifies viral loads, such as in SARS-2, aiding in tracking virus spread, surveillance, public healthcare, and vaccine development.
-Source: The Hindu
