Nobel Lecture: Emmanuelle Charpentier, Nobel Prize in Chemistry 2020 | Summary and Q&A

Summary

In this lecture, the speaker discusses the CRISPR-Cas9 technology, which is a method for genome editing. They explain the transformative nature of this technology, its applications, and its origins in the study of bacteria and viruses. The speaker emphasizes the importance of continuing research in microbiology and thanks the scientists who have contributed to the development of CRISPR-Cas9.

Questions & Answers

Q: What is the CRISPR-Cas9 technology and what does it do?

The CRISPR-Cas9 technology is a method for genome editing that allows scientists to modify genes and their expression. It consists of a protein component called Cas9, represented as scissors, which can recognize a specific sequence on DNA and cleave it. The Cas9 protein is programmed by an RNA component to bring it to the desired site of interest.

Q: Why is the CRISPR-Cas9 technology considered transformative?

The field of genetics has seen various developments over the years, but the CRISPR-Cas9 technology brings a level of programmability, simplicity, and versatility that is unmatched. It allows scientists to study cells and organisms that were previously difficult to study and to perform precise genetics in an unprecedented manner. This technology has become widely adopted by the scientific community since its discovery in 2012.

Q: How did the speaker become interested in the study of bacteria and their interactions with the human host?

The speaker's research focus on bacteria and their interaction with the human host stems from their interest in understanding how Streptococcus pyogenes causes diseases in humans. Throughout their career, they have been intrigued by how bacteria adapt to their environment, cause diseases, and how the human host defends itself against bacterial infections. They have also developed genetic tools to study these mechanisms and have worked on transgenic mice to further understand the interaction between bacteria and the human host.

Q: What led the speaker to explore the CRISPR-Cas9 system?

While conducting research on small regulatory RNAs, the speaker came across an RNA called tracer RNA, which was well-expressed in bacterial cells. They found that this RNA could base pair with the repeats of CRISPR RNAs, indicating a potential regulatory role. Upon investigating further, they discovered that the tracer RNA was encoded near a gene associated with the CRISPR system, thus sparking their interest in studying CRISPR.

Q: Why are bacteria and archaea equipped with immune systems like CRISPR?

Bacteria and archaea can be infected by viruses and have evolved diverse immune systems to defend against the invasion of genetic elements, such as phages, plasmids, and transposons. These immune systems are crucial for the survival and fitness of microorganisms in their environment. The CRISPR-Cas systems are adaptive immune systems that allow bacteria and archaea to recognize and memorize viral infections, leading to immunity upon reinfection.

Q: How does the CRISPR-Cas9 system work?

The CRISPR-Cas9 system involves a two-step process of recognition and immunity. After a virus infects a bacterial cell, the CRISPR system recognizes the invading viral DNA and inserts a sequence into the CRISPR array, effectively memorizing the virus. Upon reinfection, the CRISPR RNAs guide the Cas9 protein to the invading viral DNA, which is then cleaved and rendered unable to replicate, providing immunity against the virus.

Q: How is the CRISPR-Cas9 system programmable?

The programmability of the CRISPR-Cas9 system comes from simplifying the RNA complex that guides the Cas9 protein. Previously, two RNA molecules were used, but researchers fused them into a single RNA molecule, known as the guide RNA. This simplification allows for more straightforward design choices and makes the technology more versatile and programmable.

Q: What applications does the CRISPR-Cas9 technology have?

The CRISPR-Cas9 technology has numerous applications in both fundamental research and clinical purposes. It allows scientists to better understand the mechanisms of life, study a wide range of cells and organisms, and perform precise genetics in an unprecedented manner. The technology has been applied in various fields, including medicine (treating genetic disorders and cancers), plant biology (crop improvement), and generating disease models.

Q: How has the CRISPR-Cas9 technology impacted the field of genetics?

The CRISPR-Cas9 technology has revolutionized the field of genetics by providing scientists with a powerful tool for studying cells and organisms of interest. It has simplified and accelerated the process of precise genetics, enabling researchers to perform multiple modifications and manipulations on the genome. The technology has been rapidly adopted by scientists and has been applied successfully in various organisms, including humans.

Q: What is the future of CRISPR research?

CRISPR research is ongoing, and new CRISPR systems are continually being identified as more bacterial and archaeal genomes are sequenced. The CRISPR toolbox is expanding, and scientists are developing novel applications and technologies based on CRISPR. The technology's impact is even more significant considering advancements in sequencing technologies, gene delivery, and cell culture methods. It is an exciting time for studying the evolution and diversity of the world through CRISPR research.

Takeaways

The CRISPR-Cas9 technology is a transformative method for genome editing, allowing scientists to modify genes and their expression with unprecedented precision. It simplifies the design process, offers programmability, and has found applications in various fields, such as medicine and plant biology. The origins of CRISPR-Cas9 lie in the study of bacteria and archaea, highlighting the importance of continuing research in microbiology. Overall, CRISPR research provides young scientists with powerful tools to study cells and organisms, and it complements the advancements in sequencing, imaging, and gene delivery technologies. The impact of CRISPR-Cas9 underscores the value of microbiology in developing new biotechnologies.