## 4 Material and Methods
### Transmission Electron Microscopy Immunogold Labeling  
Transmission electron microscopy immunogold labeling was performed according to [41] using the anti-DXR antibody described in [68] at 1:5 to 1:10 dilution. The observations were performed using the electron microscopy facilities of the Toulouse Imaging Network. **Supplementary Materials:** The following are available online at [[http://www.mdpi.com/2223-7747/9/4/462/s1](http://www.mdpi.com/2223-7747/9/4/462/s1)]([http://www.mdpi.com/2223-7747/9/4/462/s1](http://www.mdpi.com/2223-7747/9/4/462/s1)), Figure S1: A phylogenetic tree was constructed from the amino acid sequence of DXS from the following species. Table S1: Details of primer sequences and cloning procedure used to amplify the DX2.2, CMS, CMK and HDR cDNAs. Table S2: Details of primer sequences and cloning procedures used to express proteins for functional validation. Table S3: The sequence of primers used in qRT-PCR analysis. Table S4: Details of primer sequences and cloning procedure used to express full-length MEP pathway enzyme fused to FP. Table S5: Details of primer sequences and cloning procedure used to fuse the first 100 residues of DXS2.1, DXS2.2, DXR and HDS to GFP. * [PERSON] et al. (2020) [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON] Beyond the semi-synthetic artemisinin: Metabolic engineering of plant-derived anti-cancer drugs. _Curr. Opin. Biotechnol._**2020**, _65_, 17-24. [CrossRef] [PubMed]
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