• Chinese Researchers Stop Plant Virus with CRISPR-Cas

    TIME: 28 Oct 2015
    Geminiviruses are circular single-stranded DNA (ssDNA) viruses that replicate within the nuclei of plant cells, causing serious damage to many dicotyledonous crop plants, including tomato, cassava, cotton, sugar beet and pepper. During geminivirus replication, the ssDNA is converted to a double-stranded DNA (dsDNA) intermediate, from which new ssDNA is generated by rolling-circle replication.
     
     
    Researchers at GAO Caixia’s group from the Institute of Genetics and Developmental Biology, the Chinese Academy of Sciences, reported introducing the CRISPR-Cas9 genome editing system protected plants from geminiviruses infection. They demonstrated that a CRISPR-Cas-like immune system directed against a geminiviruse can be established in plants and this system could also be used in other host plants to confer resistance to other DNA viruses.
     
     
    Researchers in GAO’s lab focused on Beet severe curly top virus (BSCTV) and its hosts Arabidopsis thaliana and Nicotiana benthamiana. They designed sgRNA specifically targeting to BSCTV genome. In transgenic plants, the expression of Cas9/sgRNA significantly reduced the accumulation of BSCTV by destructing the virus genome, and the anti-viral efficiency was correlated with the expression level of Cas9. They also came to conclusion that sgRNA targets might be chosen in any part of the viral genome. This work provides a new strategy to develop anti-viral crop plants.
     
     
    The study entitled “Establishing a CRISPR–Cas-like immune system conferring DNA virus resistance in plants” was published with JI Xiang and ZHANG Huawei as the co-first authors in Nature Plants on September 28, 2015 (http://www.nature.com/articles/nplants2015144). The work was highlighted by Nature (http://www.nature.com/nature/journal/v526/n7571/full/526008e.html) and Nature Reviews Mol. Bio. (http://www.nature.com/nrm/journal/v16/n11/full/nrm4079.html). This work was supported by grants from the National Natural Science Foundation of China and the Ministry of Agriculture of China.
     
     
    Contact:
    Dr. GAO Caixia
    Institute of Genetics and Developmental Biology, Chinese Academy of Sciences
     
     
     
    Figure. The overview of sgRNA-Cas9-based sequence-specific system for conferring geminivirus resistance in plants. (Image by IGDB)