The soybean breeding technology innovation and new variety selection innovation team of crop science institute of Chinese academy of agricultural sciences took the lead in single base replacement of soybean genes and obtained homozygous mutant lines with stable phenotype by using the modified CRISPR genome editing system. This study is the first report of soybean single base substitution study, which provides a new technique and method for precise modification and single nucleotide polymorphism to improve soybean agronomic traits.

As a simple and effective genome-editing tool, CRISPR has been able to perform site-directed knockout, single-base replacement of alleles and site-directed integration of foreign DNA fragments in a variety of important crops, but successful practice in soybeans is rare.

In this study, soybean single-base editing technology system was established by combining Cas9n incision enzyme, cytosine deaminase and uracil glycosylase inhibitors, and the single-base directed substitution of key genes of soybean flowering regulation GmFT2a and GmFT4 was successfully achieved with an efficiency of 18.2% and 6.0%, respectively. Two types of single-base substitutions C→T and C→G were realized at GmFT2a target site, and C→G single-base substitutions were realized at GmFT4 target site. Single base replacement mutation can be stable inheritance. The selected GmFT2a single base replacement homozygous mutation line showed the late flower phenotype under both 16 hours of light, 8 hours of darkness and 12 hours of light, 12 hours of darkness. This is the new progress made by the team in the application of soybean genome editing technology after the CRISPR genome editing system was used to realize the targeted knockout, DNA segment deletion and multi-gene mutation of soybean genes, which further expanded the application scope of soybean genome editing tools and improved agronomic traits.

Source: http://news.bioon.com

Time: 2020.04.23