CRISPR (ˈkrɪspər) (an acronym for clustered regularly interspaced short palindromic repeats) is a family of DNA sequences found in the genomes of prokaryotic organisms such as bacteria and archaea. These sequences are derived from DNA fragments of bacteriophages that had previously infected the prokaryote. They are used to detect and destroy DNA from similar bacteriophages during subsequent infections. Hence these sequences play a key role in the antiviral (i.e. anti-phage) defense system of prokaryotes and provide a form of acquired immunity. CRISPR is found in approximately 50% of sequenced bacterial genomes and nearly 90% of sequenced archaea. Cas9 (or "CRISPR-associated protein 9") is an enzyme that uses CRISPR sequences as a guide to recognize and cleave specific strands of DNA that are complementary to the CRISPR sequence. Cas9 enzymes together with CRISPR sequences form the basis of a technology known as CRISPR-Cas9 that can be used to edit genes within organisms. This editing process has a wide variety of applications including basic biological research, development of biotechnological products, and treatment of diseases. The development of the CRISPR-Cas9 genome editing technique was recognized by the Nobel Prize in Chemistry in 2020 which was awarded to Emmanuelle Charpentier and Jennifer Doudna. The discovery of clustered DNA repeats took place independently in three parts of the world. The first description of what would later be called CRISPR is from Osaka University researcher Yoshizumi Ishino and his colleagues in 1987. They accidentally cloned part of a CRISPR sequence together with the "iap" gene (isozyme conversion of alkaline phosphatase) from the genome of Escherichia coli which was their target. The organization of the repeats was unusual. Repeated sequences are typically arranged consecutively, without interspersing different sequences. They did not know the function of the interrupted clustered repeats. In 1993, researchers of Mycobacterium tuberculosis in the Netherlands published two articles about a cluster of interrupted direct repeats (DR) in that bacterium.

About this result
This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.
Related courses (18)
BIOENG-320: Synthetic biology
This advanced Bachelor/Master level course will cover fundamentals and approaches at the interface of biology, chemistry, engineering and computer science for diverse fields of synthetic biology. This
ENG-436: Food biotechnology
The course will deliver basic knowledge on the principles of food fermentation and enzyme technology. The course will also present benefits that food biotechnology can bring in terms of Nutrition & He
BIO-341: Dynamical systems in biology
Life is non-linear. This course introduces dynamical systems as a technique for modelling simple biological processes. The emphasis is on the qualitative and numerical analysis of non-linear dynamical
Show more
Related publications (32)

Development of multiplexed single-molecule imaging techniques to study chromatin invasion dynamics of chromatin effector proteins

Kristina Makasheva

DNA-binding proteins physically interact with the DNA and directly affect genomic functions. The eukaryotic genome is compacted into chromatin, limiting the DNA access to nuclear factors. In this Ph.D. thesis, I explored the dynamic mechanisms, that allow ...
EPFL2023

Secondary structure of the human mitochondrial genome affects formation of deletions

Jacques Fellay, Konstantin Popadin

BackgroundAging in postmitotic tissues is associated with clonal expansion of somatic mitochondrial deletions, the origin of which is not well understood. Such deletions are often flanked by direct nucleotide repeats, but this alone does not fully explain ...
BMC2023

Archaeal type IV pili stabilize Haloferax volcanii biofilms in flow

Alexandre Louis André Persat, Lorenzo Anton-Louis Talà, Pascal Damian Odermatt

Multicellular communities of contiguous cells attached to solid surfaces called biofilms represent a common microbial strategy to improve resilience in adverse environments.1-3 While bacterial biofilms have been under intense investigation, whether archaea ...
Cambridge2023
Show more
Related concepts (22)
Virus
A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsky's 1892 article describing a non-bacterial pathogen infecting tobacco plants and the discovery of the tobacco mosaic virus by Martinus Beijerinck in 1898, more than 11,000 of the millions of virus species have been described in detail.
Gene knockdown
Gene knockdown is an experimental technique by which the expression of one or more of an organism's genes is reduced. The reduction can occur either through genetic modification or by treatment with a reagent such as a short DNA or RNA oligonucleotide that has a sequence complementary to either gene or an mRNA transcript. If a DNA of an organism is genetically modified, the resulting organism is called a "knockdown organism.
Gene knockout
Gene knockouts (also known as gene deletion or gene inactivation) are a widely used genetic engineering technique that involves the targeted removal or inactivation of a specific gene within an organism's genome. This can be done through a variety of methods, including homologous recombination, CRISPR-Cas9, and TALENs. One of the main advantages of gene knockouts is that they allow researchers to study the function of a specific gene in vivo, and to understand the role of the gene in normal development and physiology as well as in the pathology of diseases.
Show more

Graph Chatbot

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.