CRISPR: A Crispy Gift from Microorganism to Mankind
Every living species has its battle to fight for their existence. While we are fighting against infectious bacteria, these microorganisms are on constant attack from their own enemy, virus. In this microscopic warfare, both bacteria and viruses are well-equipped with sophisticated tools against each other. One such tool is CRISPR that bacteria use against the virus. CRISPR is a molecular scissor that can selectively attack the DNA of a virus and cut it into pieces. This damage in the DNA does not allow the virus to grow inside bacteria and kill. Over the years, scientists have harnessed and nurtured this bacterial defense CRISPR and developed promising gene-editing technologies to address numerous genetic diseases. We will discuss the fascinating story of CRISPR that ensured the 2020 Nobel Prize in Chemistry to Prof. Jennifer Doudna and Prof. Emmanuelle Charpentier for their groundbreaking discovery.
Martin Jinek, Krzysztof Chylinski, Ines Fonfara, Michael Hauer, Jennifer A. Doudna, Emmanuelle Charpentier. A Programmable Dual-RNA–Guided DNA Endonuclease in Adaptive Bacterial Immunity. Science, 2012, 337, 816-821.
Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) systems provide bacteria and archaea with adaptive immunity against viruses and plasmids by using CRISPR RNAs (crRNAs) to guide the silencing of invading nucleic acids. We show here that in a subset of these systems, the mature crRNA that is base-paired to trans-activating crRNA (tracrRNA) forms a two-RNA structure that directs the CRISPR-associated protein Cas9 to introduce double-stranded (ds) breaks in target DNA. At sites complementary to the crRNA-guide sequence, the Cas9 HNH nuclease domain cleaves the complementary strand, whereas the Cas9 RuvC-like domain cleaves the noncomplementary strand. The dual-tracrRNA:crRNA, when engineered as a single RNA chimera, also directs sequence-specific Cas9 dsDNA cleavage. Our study reveals a family of endonucleases that use dual-RNAs for site-specific DNA cleavage and highlights the potential to exploit the system for RNA-programmable genome editing.
Our Research Group has received funding from DBT-SERB through Ramalingaswami Fellowship
“My stability is my science”
The ceremony will be at 4:00pm PST on Tuesday, December 8th. The award ceremony is being recorded and will be shared on the 10th along with the rest of the Laureate's award presentations.