CRISPR/Cas9-Based Mutagenesis of Starch Biosynthetic Genes in Sweet Potato (Ipomoea Batatas) for the Improvement of Starch Quality

Hongxia Wang, Yinliang Wu, Yandi Zhang, Jun Yang, Weijuan Fan, Hui Zhang, Shanshan Zhao, Ling Yuan, Peng Zhang

Research output: Contribution to journalArticlepeer-review

33 Scopus citations

Abstract

CRISPR/Cas9-mediated genome editing is a powerful technology that has been used for the genetic modification of a number of crop species. In order to evaluate the effcacy of CRISPR/Cas9 technology in the root crop, sweet potato (Ipomoea batatas), two starch biosynthetic pathway genes, IbGBSSI (encoding granule-bound starch synthase I), and IbSBEII (encoding starch branching enzyme II), were targeted in the starch-type cultivar Xushu22 and carotenoid-rich cultivar Taizhong6. I. batatas was transformed using a binary vector, in which the Cas9 gene is driven by the Arabidopsis AtUBQ promoter and the guide RNA is controlled by the Arabidopsis AtU6 promoter. A total of 72 Xushu22 and 35 Taizhong6 transgenic lines were generated and analyzed for mutations. The mutation effciency was 62-92% with multi-allelic mutations in both cultivars. Most of the mutations were nucleotide substitutions that lead to amino acid changes and, less frequently, stop codons. In addition, short nucleotide insertions or deletions were also found in both IbGBSSI and IbSBEII. Furthermore, a 2658 bp deletion was found in one IbSBEII transgenic line. The total starch contents were not significantly changed in IbGBSSI- and IbSBEII-knockout transgenic lines compared to the wild-type control. However, in the allopolyploid sweet potato, the IbGBSSI-knockout reduced, while the IbSBEII-knockout increased, the amylose percentage. Our results demonstrate that CRISPR/Cas9 technology is an effective tool for the improvement of starch qualities in sweet potato and breeding of polyploid root crops.

Original languageEnglish
Article number4702
JournalInternational Journal of Molecular Sciences
Volume20
Issue number19
DOIs
StatePublished - Oct 1 2019

Bibliographical note

Funding Information:
This work was supported by grants from the National Key R & D Program of China (2018YFD1000700, 2018YFD1000705), the National Natural Science Foundation of China (31771854), the China Scholarship Council (201804910055), and the Key Laboratory of Biology and Genetic Improvement of Tuber and Root Crop, Ministry of Agriculture and Rural Affairs, P.R. China (No. NYBSL201801). We thank Sitakanta Pattanaik and Layne Ellen Harris from the University of Kentucky for corrections to the manuscript.

Funding Information:
Funding: This work was supported by grants from the National Key R&D Program of China (2018YFD1000700, 2018YFD1000705), the National Natural Science Foundation of China (31771854), the China Scholarship Council (201804910055), and the Key Laboratory of Biology and Genetic Improvement of Tuber and Root Crop, Ministry of Agriculture and Rural Affairs, P.R. China (No. NYBSL201801).

Publisher Copyright:
© 2019 by the authors. Licensee MDPI, Basel, Switzerland.

Keywords

  • CRISPR/Cas9
  • Genome editing
  • IbGBSSI
  • IbSBEII
  • Sweet potato

ASJC Scopus subject areas

  • Catalysis
  • Molecular Biology
  • Spectroscopy
  • Computer Science Applications
  • Physical and Theoretical Chemistry
  • Organic Chemistry
  • Inorganic Chemistry

Fingerprint

Dive into the research topics of 'CRISPR/Cas9-Based Mutagenesis of Starch Biosynthetic Genes in Sweet Potato (Ipomoea Batatas) for the Improvement of Starch Quality'. Together they form a unique fingerprint.

Cite this