Biopolym. Cell. 2025; 41(2):88.
http://dx.doi.org/10.7124/bc.000B12
Structure and Function of Biopolymers
Synthesis and characterization of non-infectious hop latent viroid circular RNA using group I self-splicing ribozyme system
1, 2Yan J., 3Spyrydonov V. G., 1Dall’Agata M., 4Melnychuk M. D., 1Yu W.
  1. Shanghai Gene Era Bio–Science, Co, Ltd
    No. 211, Huancheng East Road, Fengxian distr., Shanghai, China, 201400
  2. School of Life Sciences, Fudan University
    220, Handan Rd., Yangpu Distr., Shanghai, China, 200437
  3. Elbis UAB, Ltd. 6A, Mokslininku g.,
    Vilnius, Lithuania, LT–08412
  4. Quinta Essentia: Fabula Prima, Ltd.
    10/15, Peowiakow Ul., Lublin, Poland, 20–007

Abstract

Aim. Hop latent viroid (HLVd) poses a major threat to Cannabis sativa cultivation, with up to 90% infection rates and 70% THC loss. Reliable non-infectious positive controls are needed for diagnostics. Methods. We synthesized non-infectious HLVd circular RNA using a group I self-splicing ribozyme system. The product was characterized by RNase R digestion, RT-PCR, and sequencing to confirm circularization and the ribozyme-derived joining sequence. Results. Structural analysis showed the synthetic RNA retained high stability (ΔG = –90.4 kcal/mol) compared to native HLVd (ΔG = –93.8 kcal/mol), with introduced mutations preventing replication. The molecule remained stable from –20°C to 37°C for 10 days and performed consistently as a PCR positive control. The infection assays in cannabis confirmed its non-infectious nature. Conclusion. The synthetic HLVd circRNA provides a safe, stable positive control for diagnostics and a model for viroid research, addressing a key gap in current detection methods.
Keywords: Hop latent viroid, cannabis, Group I Permutated Intron, in vitro transcription, circRNA
Full text: (PDF, in English)

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