Knockout Mouse Phenotyping Program Highlights
Research supported by the Common Fund’s Knockout Mouse Phenotyping Program (KOMP2) has applied a new way to generate conditional knockout mice, which are mice with a gene that can be selectively eliminated in specific cells or tissues at a specific point in time. Led by Dr. K.C. Kent Lloyd, researchers at the University of California Davis modified a technology known as CRISPR, or Clustered Regularly Interspaced Short Palindromic Repeat, that uses components of a bacterial immune system to precisely target genes for deletion (for more information on CRISPR, see this New York Times article). In this new study, scientists modified the CRISPR system to enhance the specificity of gene targeting while also introducing genetic changes that allow the target gene to be conditionally deleted (or “knocked out”), rather than knocked out in all cells from the beginning of development. Researchers used the new technique to generate a conditional knockout of the Isoprenoid synthase containing domain (Ispd) gene. Mutations in the human ISPD gene are associated with the neurodevelopmental disorder Walker-Warburg syndrome, a severe form of congenital muscular dystrophy affecting the muscles, brain, and eyes, that typically results in death by 3 years of age. Ispd knockout mice die at birth, limiting their effectiveness in scientific research. The conditional Ispd knockout mice may allow scientists to distinguish the effects of Ispd deletion in disease-relevant tissues at different stages of development. Beyond this important gene, however, the new technique may allow easier, faster, and more efficient generation of conditional knockout mice for many genes, both within the KOMP2 project and in labs across the world.
Lee AY and Lloyd KC. Conditional targeting of Ispd using paired Cas9 nickase and a single DNA template in mice. FEBS Open Biology, July 2014; 4: 637-42. PMID: 25161872.
Investigators at The Jackson Laboratory have developed a novel approach that enables highly efficient generation of mouse strains from Embryonic Stem Cells (ESC). This advance overcomes a major limitation in mutant mouse production; namely, the uncertainty of whether the desired mutation created in ESC is incorporated into the mouse’s reproductive cells so that it is passed along to offspring. This process has been slow, laborious, and expensive. The Perfect Host technology ensures that ESC chimeras have gametes derived only from the ESC cell carrying the desired mutation. Thus all offspring are paternally derived from the ESC and will carry the mutation. This research was made possible through support from The Jackson Laboratory, the Maine Technology Institute, in addition to several NIH Institutes and Centers, including KOMP and the use of KOMP-generated ESC cell lines. This new technology will be extremely useful for the KOMP2 program, by reducing the number of mice needed for each experiment, and greatly increasing the speed and efficiency of mouse production.
Read an interview with KOMP2 awardee Dr. Monica Justice from Baylor College of Medicine, in which she discusses her career path, current work in hematopoietic cancers and genetic syndromes, and future goals for the KOMP2 project. Find out how her early years on the farm inspired a love of biology, what experiences sparked her interest in pediatric medicine, and how she enjoys spending time outside of the lab.
Funding Opportunity Announcement to phenotype embryonic lethal knockout mice from the International Mouse Phenotyping Consortium (IMPC)!
The IMPC, a worldwide consortium that includes KOMP2 as a member, is generating an estimated 20,000 knockout mouse strains, up to 30% of which are expected to be embryonic or perinatal lethal. This funding opportunity announcement invites applications to phenotype embryonic lethal mouse strains with a long term goal of revealing important insights into normal development in addition to a variety of diseases. This funding opportunity is supported by several NIH Institutes and Centers, and is related to, but separate from, the Common Fund’s KOMP2 program.
Read the Funding Opportunity here.
See what KOMP2 has been doing lately! Download slides about KOMP2 history, current status, and future directions here.
Seven new projects receive NIH Common Fund support in fiscal year 2011 via the KOMP2 program. The program is creating a valuable genetic resource for revealing mammalian gene function, providing insight into genes that affect human health and disease.
International Mouse Phenotyping Consortium (IMPC) Policies