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Overexpression of tryptophan decarboxylase and strictosidine synthase enhanced terpenoid indole alkaloid pathway activity and antineoplastic vinblastine biosynthesis in Catharanthus roseus

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Abstract

Terpenoid indole alkaloid (TIA) biosynthetic pathway of Catharanthus roseus possesses the major attention in current metabolic engineering efforts being the sole source of highly expensive antineoplastic molecules vinblastine and vincristine. The entire TIA pathway is fairly known at biochemical and genetic levels except the pathway steps leading to biosynthesis of catharanthine and tabersonine. To increase the in-planta yield of these antineoplastic metabolites for the pharmaceutical and drug industry, extensive plant tissue culture-based studies were performed to provide alternative production systems. However, the strict spatiotemporal developmental regulation of TIA biosynthesis has restricted the utility of these cultures for large-scale production. Therefore, the present study was performed to enhance the metabolic flux of TIA pathway towards the biosynthesis of vinblastine by overexpressing two upstream TIA pathway genes, tryptophan decarboxylase (CrTDC) and strictosidine synthase (CrSTR), at whole plant levels in C. roseus. Whole plant transgenic of C. roseus was developed using Agrobacterium tumefaciens LBA1119 strain having CrTDC and CrSTR gene cassette. Developed transgenic lines demonstrated up to twofold enhanced total alkaloid production with maximum ninefold increase in vindoline and catharanthine, and fivefold increased vinblastine production. These lines recorded a maximum of 38-fold and 65-fold enhanced transcript levels of CrTDC and CrSTR genes, respectively.

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Acknowledgements

The authors thankfully acknowledge the Director, CSIR-CIMAP, Lucknow, for providing the facilities and financial support to perform this work. AS is grateful to the Department of Science and Technology (DST), Gov. of India for providing an INSPIRE fellowship (IF120009). Authors also thank Prof. Johan Memelink of Leiden University for providing the Agrobacterium tumefaciens strain LBA1119 with a construct (<hpt-<Tdc2-<Str-gus>).

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  1. Department of Plant Biotechnology, Central Institute of Medicinal and Aromatic Plants (CIMAP), Council of Scientific and Industrial Research, PO CIMAP, Kukrail Picnic Spot Road, Lucknow, 226015, India

    Abhishek Sharma, Priyanka Verma, Archana Mathur & Ajay Kumar Mathur

  2. Division of Biochemical Sciences, National Chemical Laboratory (NCL), Council of Scientific and Industrial Research, Homi Bhabha Road, Pashan, Pune, 411008, India

    Priyanka Verma

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  1. Abhishek Sharma
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AKM and AS conceived the idea and planned the work. AS conducted the experimental work. AS and PV analyzed the results and prepared the manuscript. AKM and AM read and edited the manuscript.

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Correspondence to Ajay Kumar Mathur.

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Sharma, A., Verma, P., Mathur, A. et al. Overexpression of tryptophan decarboxylase and strictosidine synthase enhanced terpenoid indole alkaloid pathway activity and antineoplastic vinblastine biosynthesis in Catharanthus roseus. Protoplasma 255, 1281–1294 (2018). https://doi.org/10.1007/s00709-018-1233-1

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