What are gene-editing and CRISPR-Cas9?
In term of gene-editing (also known as genetic editing) is a group of technologies that allow scientists to modify the DNA of an organism. These techniques allow you to add, remove, or modify genetic material at specific locations in the genome. Several genome editing methods have been developed.
The latest is called CRISPR-Cas9, an abbreviation for a cluster of regularly spaced short palindrome repeats and CRISPR-related protein 9. The CRISPR-Cas9 system has created a lot of excitement in the scientific community for being faster, cheaper, and more. This is more accurate and efficient than other existing genome editing methods.
CRISPR-Cas9 applies a naturally occurring genome editing system in bacteria. Bacteria capture the DNA fragments of the invading virus and use them to create DNA fragments called CRISPR arrays. CRISPR arrays allow bacteria to “remember” viruses (or closely related viruses).
When the virus attacks again, the bacterium produces RNA fragments from the CRISPR array to target the virus’s DNA. The bacterium then uses Cas9 or a similar enzyme to cleave the DNA, thereby inactivating the virus.
the gene-editing tool uses a bacterial DNA fragment called Retrons.
Researchers at Harvard’s Wise Bio-Inspired Engineering Institute have created a new gene-editing tool that allows scientists to perform millions of gene experiments simultaneously. They call it Retron Library Recombineering (RLR) technology, which uses a bacterial DNA fragment called Retrons to produce a single-strand DNA fragment.
From a gene-editing perspective, CRISPR-Cas9 may be the most famous technology today. For the past few years, it has created a sensation in the scientific community and has provided researchers with the tools they need to easily alter their DNA sequences. It is more accurate than previously used techniques and has a wide range of potential uses, including life-saving treatments for a variety of illnesses.
However, this tool has some major limitations. Providing large quantities of CRISPR-Cas9 material can be difficult, but it is still a matter of research and experimentation. In addition, the Cas9 enzyme (the molecule “scissors” involved in DNA strand cleavage) often cleaves non-target sites, so the mechanism of this technique can be toxic to cells.
CRISPR-Cas9 physically cleaves DNA during the repair process and integrates the mutant sequence into its genome. At the same time, reverse transcription can introduce the mutated DNA strand into the replication cell, resulting in the strand being integrated into the DNA of the daughter cell.
In addition, reverse transcriptase can be used as a “barcode” or “name tag”, allowing scientists to track individuals in a bacterial pool. This means that it can be used for genome editing without damaging the natural DNA and can be used to perform multiple experiments with large mixtures.
The scientist at the Wyss Institute is E. An RLR test was performed on coli and found that 90% of the population added the Retron sequence after some adjustments. They were also able to prove how useful it is in large-scale genetic experiments. In their testing process, we were able to find antibiotic-resistant mutations in E. coli by sequencing retrospective barcodes instead of sequencing individual mutants, accelerating the process.
Max Schubert, the co-lead author of the study, explains:
RLR allows us to do things that CRISPR cannot do. Randomly chop the bacterial genome, convert these gene fragments into single-stranded DNA on the fly, and use them to create millions of sequences. Screening at the same time. RLR is a simpler and easier way: Using flexible gene-editing tools, you can perform very multiple experiments, eliminating the toxicity commonly found in CRISPR and mutating at the genomic level Improves the ability of researchers to explore …
For a long time, CRISPR has been seen as a strange thing that bacteria do, and understanding how to use CRISPR for genomic engineering has changed the world. Reverse transcription is another innovation in bacteria, and It may bring some significant improvements. “