2020 7 on CRISPR/Cas the latest research progress
2020 年 7 月 30 day news/Bio ValleyBIOON/—genome editing technology CRISPR/Cas9 is the journal Science as 2013 annual top ten scientific and technological progress one of the subject to people’s attention. CRISPR is a regular intervals of clustered Short Palindromic Repeat sequence of short, Cas is CRISPR-associated protein referred to. CRISPR/Cas is initially inbacteriafound in the body and isbacteriaused to identify and destroy anti-phage and other pathogens invading the defensive system.
pictures from Thomas Splettstoesser (Wikipedia, CC BY-SA 4.0) a.& nbsp;
2018 11 on 26 May, Chinese scientists he built Kui claimed the world’s first genetically edited baby—a pair of twin female baby—in the 11 month of birth. He used a powerful gene-editing tool CRISPR-Cas9 for the Twins of a gene can be modified so that their birth can be a natural resistance to HIV infection. It is also the world’s first immune AIDS gene editing Baby. This message instantly at home and abroad on the website of the rapid fermentation, causing a thousand layer waves. A part of scientists support he built Kui research, but more is questioned, or even condemned.< p>about the past 7 months, what are the major CRISPR/Cas research or found it? Small comb a bit this month Bio Valley reported the CRISPR/Cas research news, for everyone to read. p>
1.< a href="http://www.bioon.com/article/6759257.html" target="_blank">Nat Biotechnol: a novel DNA base editor to expand the precise genome editing applications
in a new study, from Massachusetts General Hospital and Harvard Medical School researchers have developed a novel genome editing technology has the potential to contribute to the understanding based on the C→G by the cytosine is mutated to guanine single nucleotide changes in the disease-related mutations. These new bases in the editor can also be minimize may cause adverse side effects of non-expected“off-target”for mutation. Relevant research results in 2020 7 November 20, published online in Nature Biotechnology Journal, thesis entitled“The CRISPR C-to-G base editors for inducing targeted DNA transversions in human cells”. Papers the corresponding author for the Massachusetts General Hospital Julian Grünewald and Dr. J. Keith Joung, PhD. The thesis of the first author to the Massachusetts General Hospital Ibrahim C. Kurt and Ronghao Zhou.
pictures from the CC0 Public Domain. p>
these by the CRISPR guide of new DNA-base editing technique is designed to efficiently induce DNA base transversions（transversion, i.e., a purine base by another pyrimidine base is replaced, or a pyrimidine base by another purine base is replaced, and will not require the“bystander”mutations level to a minimum. In this paper, these authors describe a proof-of-concept called CGBE1 C→G base editor, and it’s a smaller version: miniCGBE1.
2.< a href="http://www.bioon.com/article/6759184.html" target="_blank">Science sub-issue: the new base editor A3G-BE may be the gene editing accuracy improved up to 6000 times
in a new study, from the Chinese Academy of Sciences College, China Agricultural Academy of Sciences and the American Rice University researchers have found that one can significantly enhance gene editing accuracy of the technology. With the current is considered to be the most advanced base editor BE4max compared, they introduced a gene editing tool in disease sequence model will be based on the CRISPR editing accuracy improved up to 6000 times. Related research results published in 2020 7 May 15, The Science Advances journal, title of paper is“Single C-to-T substitution using engineered APOBEC3G-nCas9 base editors with minimum genome – and transcriptome-wide off-target effects”are. Papers the corresponding author for the Chinese Academy of Agricultural Sciences Agricultural Genome Research Institute of the second left Wei Erwei Zuo, Dr. and Rice University bio-molecular engineer Xue Sherry Gao, PhD. p>
these researchers trying to through a series of protein engineering experiments to develop a new base editor. This new cytosine base editor called A3G-BE, only by editing consecutive bases C of the second C, which greatly improves editing accuracy. p>
3.< a href="http://news.bioon.com/article/6758590.html" target="_blank">Science: the discovery of a reliable CRISPR/Cas13a system inhibitors
doi:10.1126/science. abb6151; doi:10.1126/science. abc8243
in the VI-type CRISPR-Cas antiviral reaction process, the CRISPR RNA(crRNA)to guide the Cas13 nucleic acid enzyme the indiscriminate destruction of the bacterial cell and the invader RNA, while preventing the infected host growth and the spread of the virus, thereby protecting the bacterial flora of the body from virus infection. This reaction is by Cas13 nucleic acid enzyme-mediated, it is in recognition to its guide RNA（the gRNA complementary to the viral transcription was performed after a large amount of RNA degradation. However, the virus how to fight this bacterial immune system is unclear. p>
in a new study, from the United States the Rockefeller University, Memorial Sloan Kettering Cancer Center and Cornell University researchers found that as a by a phage-coded inhibitor, AcrVIA1 with Cas13a binding, thereby blocking the gRNA and prevents such a nucleic acid enzyme activation. This indicates that AcrVIA1 can be potentially as Cas13a nucleic acid enzyme of the control switch. Related research results published in 2020 Years 7 Months 3 days Science journals, theses titled“A phage-encoded anti-CRISPR enables complete evasion of the type VI-A CRISPR-Cas immunity”in.
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pictures from the Science, 2020, doi:10.1126/science. abb6151 it. p>
they found as a encoded anti-CRISPR protein, AcrVIA1 by the Listeria phage（ϕLS46 encoding, it is possible to make Steinmann Listeria monocytogenes（Listeria seeligeri of VI-A-type CRISPR system deactivation. The use of genetics, biochemistry and structural biology, they found AcrVIA1 with Cas13a nucleic acid enzyme Wizard exposed surface interactions, blocking of the target RNA to enter and such a nucleic acid enzyme activation required for conformational change.< p>
4.< a href="http://news.bioon.com/article/6758905.html" target="_blank">Nat Biotechnol: the development of the predictable genome editor off-target activity of the tool—CHANGE-seq
in a new study, from the United States St. Jude Children’s Research Hospital, Carnegie Mellon University and the United States National Institute of standards and technology and other research institutions, researchers developed an easy-to-use and sensitive high-throughput method for determining by CRISPR-Cas9 and other genome editor caused by non-desired DNA double-strand break location. They will this method is called the CHANGE-seq（Circularization for High-throughput Analysis of Nuclease Genome-wide Effects by Sequencing it. Related research results recently published in the Nature Biotechnology Journal, thesis title is“CHANGE-seq reveals genetic and epigenetic effects on CRISPR–Cas9 genome-wide activity of”. p>
papers newsletter author, St. Jude Children’s Research Hospital Shengdar Tsai,“says Dr CHANGE-seq is the first truly scalable used to illustrate the CRISPR-Cas nucleases in the non-expected activity method. With this method, scientists can now quickly pick out the best, safest, genome editing and the target point for the treatment of editing, such as for the treatment of sickle cell diseases and for cancer immunotherapy.” p>
5.< a href="http://www.bioon.com/article/6758904.html" target="_blank">Nat Biotechnol: CAS high pink clouds team developed a plant model can predict the multi-nucleotide deletion system
CRISPR-Cas9 system has been used in Genome Engineering has been widely used. In this system, the sgRNA-guided Cas9 nuclease to generate chromosomal double-strand break（DSB, the DSB mainly through the non-homologous end connection nonhomologous end joining, NHEJ for repair, resulting in frequent long and 1 to 3 bp short insertion and deletion（indel）produce. However, these small indel heterogeneity so that the destruction of these regulatory DNA is technically challenging. Therefore, the development of a precise, predictable multi-nucleotide deletion system for these regulatory DNA of the gene function analysis and application of great significance.< br>
pictures from Nature Biotechnology, 2020, doi:10.1038/s41587-020-0566-4 it. p>
Institute of genetics and Developmental Biology Institute of high pink clouds（Gao Caixia, Professor and research team has been committed to the development of new technologies, in order to achieve efficient and specific genome engineering. In a new study, these researchers, based on cytosine deamination and base excision repair, base excision repair, BER mechanism, developed a series of APOBEC-Cas9 Fusion induced missing system APOBEC-Cas9 fusion-induced deletion system, AFID the Cas9 and human APOBEC3A（A3A, a uracil DNA-glucosidase enzyme UDG and AP lyase combined, the success in rice and wheat genome induced a new type of precise, predictable polynucleotide missing. Related research results recently published in the Nature Biotechnology Journal, thesis title is“Precise, predictable multi-nucleotide deletions in rice and wheat using APOBEC–Cas9”.
6.< a href="http://news.bioon.com/article/6759397.html" target="_blank">Nat Metab: new study helps in the treatment of Type I diabetes
when a person’s own immune system destroys the pancreas to produce insulin beta cells, it will lead to type 1 diabetes. In recent years, scientists have learned how to grow a large number of alternative β cells, but researchers are still trying many ways to protect these cells from immune attack. Recently, a Joslin Diabetes Center researchers now discovered a new method that could eventually help to protect the transplanted beta cells or slow the onset of disease. The mouse model and human cell studies show that targeting a technique called“renal enzyme renalase”the protein can enhance β-cell resistance to protect itself resistant to the immune system attack. Relevant results published in a recent of the Nature Metabolism of the magazine. p>
first, the authors use a method based on CRISPR gene editing method of screening techniques, and use from“non-obese diabetic”（NOD）mouse β cell lines used to simulate type 1 diabetes. “Genomic CRISPR screening is to discover new targets of a powerful tool, and we hope it can help us to find the protection of β cells of any mutants,”co-author Yi said. Through the survival of β cells for CRISPR screening author got more than a dozen interest of the genes. The most striking is the renal enzyme genes, previous studies have shown that it is with Type 1 diabetes. p>
next, the researchers created the NOD mouse β-cells, some of which “knock-out”of the renal enzyme gene. They will these cells are transplanted into patients with autoimmune diabetes of NOD mice body. The results showed that the wild-type β cells after transplantation and ultimately death, but the renal enzyme gene knockout cells eventually survive.
7.< a href="http://news.bioon.com/article/6759296.html" target="_blank">Science new discovery! Huge phage or possess an ideal gene editing operation of the mini-Cas protein—CasΦ protein! a>
recently, an article published in the international journal Science entitled“CRISPR-CasΦ from huge phages is a hypercompact genome editor”of the study, from the University of California and other institutions of scientists have found through research, huge phage（megaphages may have the ideal gene editing of the mini-Cas protein. p>
CRISPR-Cas9 and its associated gene editing tools the core of the DNA-cutting protein originally derived from the bacteria, but the recent discovery of a variety of Cas proteins is clearly in the viruses that infect bacteria evolved; the new Cas protein is the largest known bacterial infection of the virus, phage found, but which is also so far found the most compact of the work of the Cas mutant, which only the Cas9 protein size of a���Around. Smaller, more compact Cas protein is often easier to be transported to the cells for gene editing, because it can be loaded into a small transportation carrier, is currently the most popular kind of transport the carrier is adeno-associated virus, AAV, a super compact Cas protein in the AAV inside of the other additional“cargo”stay out of space, as currently known minimum Cas protein, the researchers the newly discovered CasΦ（Cas-phi in is transported to the cells to manipulate the crop gene or treatment of human diseases, which than the current gene-editing tool has more advantages.< br>
Image Sources: Basem Al-Shayeb and Patrick Pausch, UC Berkeley. p>
researchers Patrick Pausch said, the adenovirus is to transport the gene carrier is the perfect Trojan horse, which can be very easily a virus can be programmed and make it reach the body of almost any site, but your intelligence will be a very small Cas9 into such a virus to be transported, if there is another one as compared to the Cas9 in terms of the more compact of the CRISPR-Cas system, then there is enough space to accommodate other additional components, different proteins will be fused to the Cas proteins, DNA repair template or the other can adjust the Cas protein and the control gene editing results in the factor in. Obviously, these giant phages can use CasΦ protein to trick the bacteria to resist the virus, rather than yourself.< p>
8.< a href="http://www.bioon.com/article/6758875.html" target="_blank">PLoS Biol: the scientist is expected to develop to sell off the target rate of the lower of security CRISPR gene editing technology
doi:10.1371/journal. pbio. 3000747
the CRISPR system is a targeted editing of the genome a powerful tool, which has obvious therapeutic potential, however, it often will not be appropriate to edit some of the“off-target”off-target sites, recently, a study published in the international journal PLoS Biology on the research from Wenzhou Medical University and other institutions of scientists by research showing that mutations in the CRISPR gene editing system is the core of the enzyme class might be able to improve its editorial accuracy, the relevant results of the study or for gene editing to provide a compared the use of unmodified enzymes system more safe therapeutic strategy. p>
in order to in-depth research from Staphylococcus aureus Cas9 can be modified to Hi-Fi to cut the intended target, the researchers developed a series of novel Cas9 mutants, while maintaining the desired bit point higher activity at the same time detected which distinguish the imperfect pairing of ability, they found a mutant, which are able to distinguish and reject the gRNA and DNA between single base pair mismatches, whether the target point of how this can make fidelity compared to the original enzymes increased 93-fold; the researchers indicated that this mutation affects a portion of the identify the structure of the domain, i.e., the enzymes of the special region, the region can coordinate enzymes and the gRNA-DNA complexes between the contacts, this mutation may weaken these contacts, so you can ensure that only from a perfect sequence match to the strongest pair to be able to trigger the enzymes activity. p>
9.< a href="http://www.bioon.com/article/6758642.html" target="_blank">Nature major progress! The development of efficient mitochondrial DNA base editor! a>
in a study recently published in Nature on a breakthrough research on A bacterial cytidine deaminase toxin contains CRISPR-free mitochondrial base editing, the researchers will sword into a plow, will a bacterial toxin into a genome editing tool, this is the first time can be the cells”power plant”mitochondrial DNA for a precise change. The tool in the body cells of laboratory experiments played a role, it may open a door to new research the door-and the future of dozens of difficult to treat by the mitochondrial DNA (mtDNA)mutations cause the disease to new therapies. These rare diseases, including Leber hereditary optic neuropathy and fatal infant myocardial disease, the overall incidence of about 1 / 4000 to. So far, these disease research has been hampered, in part because there is no way in the mouse strains, the replication of this mutation. p>
the new study in the development of this new tool combines the CRISPR characteristics and a method called transcription activator-like effectors(TALEs)of the old technology, the three team together to create this new tool.” Let���A project so interesting and, ultimately, the success of the reason is the three laboratories organic to get together, and it is science let’s get together.” Broad Institute researchers, the study corresponding author David Liu said. p>
10.< a href="http://www.bioon.com/article/6759294.html" target="_blank">Nat Methods: the development of the CRISPR-assisted technology to detect living cells in RNA-binding proteins the future is expected to assist human disease research
although currently scientists are still not completely understood RNA molecule diversity, but they believe that with these RNA molecules The Binding of RNA-binding proteins or with various body diseases is directly related to, recently, a study published in the international journal Nature Methods, entitled“CRISPR-assisted detection of RNA–protein interactions in living cells”of the study, from the City University of Hong Kong and other Agency scientists have developed a called CARPID novel detection method, which can identify viable cells in the special RNAs the binding protein, such new method or can be applied to multiple types of cell research, such as from the identification of cancer biomarkers to detect the treatment of various viral diseases of potential drug targets and the like.
Molecular Biology the Central dogma DNA transcription become RNA, and RNA is ultimately translated into protein, but in fact, only about 2% of the RNAs can encode proteins, while the remaining 98%is called non-coding RNAs（ncRNA）RNA molecule is due to its mysterious function is treated as“dark matter.” In recent years, scientists have begun research efforts aimed at unraveling the RNA of the real function, especially long-chain non-coding RNAs（lncRNA, the length is only 200 more nucleotides, the lncRNA is widely accepted to be involved in the regulation of gene expression of important cellular components, while it is also the researchers are most interested in the study of the RNA of one. p>
11.< a href="http://www.bioon.com/article/6758938.html" target="_blank">Curr Gene Ther: based on the ADAR of the artificial RNA editing is expected to be used for gene therapy
many of the point mutations causing the disease are not readily available treatment methods. Japan Hokuriku Advanced Institute of Science and technology of Toshifumi Tsukahara Professor and his colleagues are working on a the use of artificial RNA editing method of treatment. Artificial site-directed RNA editing is a modification of the genes and ultimately the regulation of protein function an important technology. Tsukahara team is to try to by artificial RNA editing to modify the transcription of RNA the genetic code to treat genetic disease.< br>
images from Current Gene Therapy, 2020, doi:10.2174/1566523220666200516170137 it. p>
RNA editing is a physiological process, is widely present in vivo, may be from a single gene to produce a variety of different functions of the protein. In mammals, the RNA strand of a nucleotide C or A May Be A nucleotide sequence-specific hydrolysis after deamination, so that C is U-substituted, A is I, inosine replace it. Given I and C form a Watson-Crick G Watson-Crick）base pairs, and therefore in the genetic code, the I and G, respectively. These Bases Conversion is due to A or C deamination occurs, it has been found that this is by ADAR and APOBEC family of enzymes catalysis. Recently, it has been reported in a variety of using ADAR for manual RNA editing RNA repair technology.< p>in an article recently published in Current Gene Therapy Journal on paper, Tsukahara team reviewed the app ADAR to restore the genetic code of the latest research results, as well as in the use of ADAR artificial RNA editing involved in the process in different ways. They also talked about the ADAR of the various isomers of comparative studies. Therefore, they will try to artificial RNA editing and ADAR the role of a detailed overview, focusing on the enzymatic point A→I Editing. p>
most of the artificial RNA editing system is the use of a catalytic enzyme of the ADAR active site and with the target complementary to the guide RNA（gRNA to recruit the active site of the target RNA on. An artificial RNA editing method is to use the chemical method. Vogel and colleagues used the SNAP tag will ADAR and the gRNA are connected, and reports the system in vitro and in vivo are effective. However, this technique requires a continuous supply of effector molecules to be effective. It is reported that it can also take advantage of RNA-binding proteinWhite will be the gRNA with the enzyme combination. Two originated from the bacteriophage of the tethered system is typically used for eukaryotic organisms: the Lambda N system and the MS2 system. Use of the ADAR enzyme with the MS2 system can be implemented in the genetic code of the recovery, in the gene therapy aspect of having prospects. Biological Valley Bioon.com
Published at Thu, 30 Jul 2020 20:45:53 +0000