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bioRxiv · 10.1101/254698

Engineering Plant Architecture via CRISPR/Cas9-mediated Alteration of Strigolactone Biosynthesis

Butt, H.·Jamil, M.·Wang, J. Y.·Al-Babili, S.·Mahfouz, M.
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Abstract

Precision plant genome engineering holds much promise for targeted improvement of crop traits via unprecedented single-base level control over the genetic material. Strigolactones (SLs) are a key determinant of plant architecture, known for their role in inhibiting shoot branching (tillering). Here, we used CRISPR/Cas9 in rice (Oryza sativa) for targeted disruption of CAROTENOID CLEAVAGE DIOXYGENASE 7 (CCD7), which controls a key step in SL biosynthesis. The ccd7 mutants exhibited a striking increase in tillering, combined with a dwarf phenotype, which could be rescued by application of the synthetic SL analog GR24. Striga germination assays and liquid chromatography-mass spectrometry analysis showed that root exudates of ccd7 mutants were also SL deficient. Taken together, our results show the power of CRISPR/Cas9 for targeted engineering of plant architecture and for elucidating the molecular underpinnings of architecture-related traits.

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Butt, H., Jamil, M., Wang, J. Y., Al-Babili, S., Mahfouz, M.. 2018-01-27. Engineering Plant Architecture via CRISPR/Cas9-mediated Alteration of Strigolactone Biosynthesis. https://doi.org/10.1101/254698

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