Imaging with CRISPR/Cas9
Since CRISPR/Cas9 was firstly applied for genome engineering, this technology has been widely used all over the world. Consisting of two members, Cas9 and guide RNA, CIRSPR/Cas9 can precisely edit genome following the design. By CRISPR/Cas9, genome editing (such as gene knockout, tag insertion and point mutation) becomes easier and more efficient. Recently, researchers developed a novel approach for imaging based on CRISPR/Cas9 system.
Genomic DNA, as an important genetic substance, is one of the key objects for research. DNA FISH, an image technology, has been widely used to visualize sequence-specific chromatin domains or genes for research and diagnostic purposes. However, DNA FISH requires harsh treatments of heat and formamide to denature dsDNA to allow probe hybridization and is limited by high cost. Thus, researcher developed a Cas9-based assay called CASFISH to simplify the test. Using fluorescently labeled nuclease-deficient Cas9 protein assembled with guide RNA, researcher successfully visualize nonrepetitive genomic sequences. The Cas9/sgRNA complex, which is assembled in vitro, is stable and binds to the specific target DNA. CASFISH assays with different colored dCas9/sgRNA complex allow multicolor labeling of target loci in cells. Taken together, CASFISH is a rapid, cost-effective and convenient assay and allows to detect genes within undisturbed nucleic of fixed cells or living cell.
Figure 1. CASFISH
Besides, CAISPR/Cas9 system also is a powerful tool for live-cell imaging of genomic loci. By transfecting GFP-dCas9 and sgRNA into cells, researcher successfully visualize the specific genome sequence in living cells. This method can utilize fluorescent label to track the movement of target sequences in living cells.
Table 1. Comparison of three different imaging technology
Advantage
- Easy-to-use
- Rapid and efficient
- Affordable price
- Imaging in living cells
Creative Biogene provides various labelled dCas9 products for imaging in cells, such as cyt3-lableled dCas9 protein, dCas9-GFP protein. Custom products and services are welcome as well.
References:
- Wulan Deng, et al. 'CASFISH: CRISPR/Cas9 mediated in situ labeling of genomic loci in fixed cells', PNAS, 2015, 12.
- Yuexin Zhou, et al. 'Painting a specific chromosome with CRISPR/Cas9 for living cell imaging', Cell Research, 2017, 27, 298-301.
* For research use only. Not intended for any clinical use.