marginata; a prospective liverwort an alternate source of -like compounds Tajammul Hussain and Oliver Kayser Department of Technical Biochemiestry, Faculty of Bio-Chemical Engineering, Technical University Dortmund [email protected]; [email protected] INTRODUCTION iii) Characterization of stilbene synthase The liverwort Radula marginata belongs to the division of land . are an early-diverged group of land plants. The division comprising of A around 20,000 species and are divided into three phyla: mosses, hornworts and liverworts. Among them liverworts are the most abundant consisting of 6000-8000 species. Radulales is an order of subclass Jungermanniidae in this phylum. Radulaceae is the only family in this order, comprises Radula genus and 283 species. Radula marginata is of significant interest since and perrottetinenic acid 1,2 had been reported. These compounds are structural analogs to (Δ9- THC), a psychopharmacological compound in sativa L. Recently, agonistic Chalcone synthase (HsCHS) Stilbene synthase (RmSTS Model) Stilbenecarboxylate synthase (MpSTCS2) (Huperzia serrata ) (Radula marginata) (Marchantia polymorpha) activity of these compounds with cannabinoid receptor 1 (CB1) 3–5 further confirmed the B potential of this specie in cannabinoid-based pharmaceutical industry. Therefore genetic- LOCAL Quality Estimate Z-score Comparison with Non-redundant Set of PDB Structures

level understanding of secondary metabolic pathways that lead to the synthesis of 1.0 QMEAN6 -0.18 1.0 cannabinoid-like natural compounds would be desirable. 0.8 All Atom -0.26

0.6 CBeta -0.80 0.5 Solvation 0.50 0.4 RESULTS Torsion -0.35 0.0 0.2

SS Agree 0.64 Score QMEAN6 Normalized 0.0 Predicted Local Similarity to Local Similarity Predicted Target -0.5 i) de-novo assembly and annotation 0 50 100 150 200 250 300 350 400 ACC Agree -0.26 0 100 200 400300500 600 Paired-end Illumina Hiseq-2000 platform generated 30 million raw reads for each pair. Residue Number -6 -5 -4 -3 -2 -1 0 1 2 Protein Size (Residues) C Raw reads filtered and quality trimmed. Trinity was used for de-novo assembly of raw β1β2 β3 RmSTS Target 100 HsCHS 96 reads and resulted in 87,460 transcripts with a median contig size of 303 bp, and a MpSTCS2 93 β4 β5 β6 maximum of 23,874 bp (Table 1). RmSTS Target 200 HsCHS 196 MpSTCS2 193 β7 β8β9β10 β11 RmSTS Target 300 HsCHS 295 Table 1: Sequencing Summary MpSTCS2 292 β09 β13β12 RmSTS Target 386 HsCHS 379 MpSTCS2 378

Figure 3: A) Crystal structure of stilbene synthase model compared with Chalcone synthase-like polyketide (Left, 3awk.1) and Stilbene carboxylate synthase from Marchantia polymorpha (right, 2p0u.1.A). B) Quality estimate of local similarity, Z score of the predicted STS model in Radulamarginata. C) Alignment of the identified stilbene synthase in Radula marginata with the respective template model, blue boxes are the beta sheets, yellow boxes in the alignment are the variable sites for both models used as well as in olivetolic acid from Cannabis sativa.

Figure 1: Overall annotation results from BLAST, InterProScan (IPR), Gene ontology (GO) and KEGG pathway databases.

Assembled transcripts were BLAST against publically availabale databases, followed iv) Metabolomic detection of CBGA-analog scanning with InterProScan (IPR) for protein signatures, assigning Gene ontology (GO) The CBGA analog was identified with the HPLC-ESI-MS-MS approach. The positive ESI term and finally map against KEGG database for active pathways in Radula marginata mass spectrum of the CBGA bibenzyl analog showed an [M+H]+ ion at m/z 395, a (Figure 1). predominant [M+H-H2O]+ion at m/z 377, and fragment ions at m/z 271 [M+H-C9H16] and m/z 267 [M+H-H2O-C8H4]. The ion m/z 253 is probably the result of degradation processes eliminating two protons, resulting in [M+H-H2O-C9H16]. Together these ii) Identification of precursor genes for the bioynthesis indicate the presence of the CBGA analogue’s bibenzyl structure in the methanolic of cannabinoid-like compound extracts of R. marginata (Figure 4). Intens 5 A B [%] x105 4 3 MEP Pathway 120 2 1 0 x104 Pyruvate + Glyceraldehyde 3 phosphate 100 1.25 1.00 0.75 Rm-tct_1244627 DXS 80 0.50 CO 2 0.25 60 0.00 100 200 300 400 500 600 m/z 1-Deoxy-D-xylose 5-phosphate FPKM NADPH 40 Intens Rm-tct_127235 DXR NADP+ [%] 20 x105 3 2-C-Methyl-D-erythritol 4-phosphate 0 CTP Rm-tct_1145108 ISPD 2 PPi Rm_DXSRm_DXR Rm_STS Rm_ISPDRm_ISPERm_ISPF-1Rm_ISPF-2Rm_ISPGRm_ISPHRm_GPPS 1 4-(Cytidine 5'-diphospho)-2-C-methyl-D-erythritol C ATP 1.2 Rm-tct_124667 ISPE 0 ADP 1.0 260220240 280 300 320 340 360 380 400m/z

2-Phospho-4-(cytidine 5’-diphospho)-2-C-methyl-Derythritol 0.8 Figure 4: Tandem mass spectra of the bibenzyl analog of cannabigerolic acid with m/z 395.214 Rm-tct_390072 ISPF 0.6 Rm-tct_800710 CMP 0.4 2-C-Methyl-D-erythritol 2,4-cyclodiphosphate eaieexpression Relative Conclusion and future prospects 2x reduced ferreoxin 0.2 ISPG Rm-tct_127275 2x oxidized ferredoxin + H2O 0.0 This is the first transcriptomic study for the Radulaceae family. We captured, assembled 1-Hydroxy-2-methyl-2-butenyl 4-diphosphate and annotate the R. marginata transcriptome. Identification of the precursor genes for the 2x reduced ferreoxin + 2H+ Rm_DXSRm_DXRRm_ISPDRm_ISPERm_ISPGRm_ISPHRm_GPPSRm_STS Rm-tct_132279 ISPH cannabinoid-like compound, validation of these genes through quantitative real time 2x oxidized ferredoxin + H2O Rm-tct_135369 Acetyl CoA ATP+HCO3 Cinnamic acid Tyrosine expressional analysis, characterization of the central precursor and finally detection of IPP Rm-tct_904060 Acetyl CoA carboxylase Isopentenyl diphosphate dimethyl ally diphosphate Rm-tct_135581 ADP+P compound from metabolomics approach lead us to speculate that the cannabinoid-like

3x Malonyl-CoA p-Cumaroyl-CoA pathway is likely to be conserved in lower and high land plants with the exception of first Rm-tct_77426 GPPS Rm-tct_105876 Stilbene synthase intermediate. However, these findings require further experimental work to confirm this geranyl pyrophosphate (GPP) stilbene acid (SA) proposed novelty. Overall, this study would serve as a reference transcriptomic resource Figure 2: Candidate precursor genes for cannabinoid biosynthesis in Radula marginata: A)Identification of candidate for Radulaceae family to further explore especially Radula marginata. Moreover, this study genes for cannabinoid biosynthesis in R. marginata. GPP transcripts as well as all the upstream genes were identified. Genes also proposes R. marginata as an alternate to Cannabis sativa for cannabinoid-like with Rm-tct_xxx prefix were identified in this study. B)Transcriptomic expression of identified genes determined from FPKM C) Relative expression of candidate gene by real time quantitative PCR (RT-qPCR). compounds.

References Acknowledgment 1. Toyota, M. et al. New bibenzyl cannabinoid from the New Zealand liverwort Radula marginata. Chem. Pharm. Bull. This study was supported by the DISCO under the grant agreement 613513. We thank (Tokyo). 50, 1390–1392 (2002). Mr. Sven Buijssen for providing the computationl resource, LiDong HPC. We also thank 2. Park, B. H. & Lee, Y. R. Concise synthesis of perrottetinene with bibenzyl cannabinoid. Bull. Korean Chem. Soc. 31, Dr. Felix Stehle for ESI-MS/MS and Dr. Pawel Rodziewicz for GC/MS analysis. Thanks to 2712–2714 (2010). Dr. Richard ESpley for providing the Radula material and expressionl analysis. 3. Russo, E. B. Beyond Cannabis: Plants and the Endocannabinoid System. Trends Pharmacol. Sci. 37, 594–605 (2016). For further details: 4. Gachet, M. S., Schubert, A., Calarco, S., Boccard, J. & Gertsch, J. Targeted metabolomics shows plasticity in the Hussain T, Plunkett B, Ejaz M, Espley RV and Kayser O (2018) Identification of Putative evolution of signaling lipids and uncovers old and new endocannabinoids in the kingdom. Sci. Rep. 7, 1–15 (2017). Precursor Genes for the Biosynthesis of Cannabinoid-Like Compound in Radula 5. Soethoudt, M. et al. Cannabinoid CB 2 receptor ligand profiling reveals biased signalling and off-target activity. (2017). marginata. Front. Plant Sci. 9:537.doi: 10.3389/fpls.2018.00537