Molecular Pathogens, 2025, Vol.16, No.4, 147-158 http://microbescipublisher.com/index.php/mp 149 enters plant cells, it can trigger the small interfering RNA (siRNA) pathway to degrade viral RNA. However, viruses have also evolved a countermeasure strategy, and many potato viruses encode RNA silencing inhibitory proteins (VSRs). For example, the HC-Pro protein of PVY and the P25 protein of PVX are both powerful RNA silencing inhibitors that can bind to the host's silencing signaling pathway factors, thereby hindering the antiviral silencing response (Figure 1). Recent studies have found that certain defense-related proteins of the plant themselves can interact with virus silencing inhibitors to enhance resistance. Studies have identified that a type I protease inhibitor (PI) in potatoes can bind to P25 protein of PVX, hindering the silencing and inhibiting function of P25, thereby improving resistance to PVX (Shen and Wang, 2025). This interaction mechanism suggests that plants can use their own proteins to directly interfere with the function of viral pathogenic factors. Figure 1 The viruses accumulate and symptoms develop in the RiStEXA1 and control plants (WT) inoculated with PVYO (a), PVX (b), and PVM (c). Relative virus accumulation was determined using qRT–PCR with total RNAs extracted from the non-inoculated upper leaves at 10 and 15 dpi. Symptoms on plants and systemic leaves were observed and photos were taken at ~25 dpi. Data are presented as means ± SD (n = 3) relative to WT plants, and EF1α was used as the normalizer. Three independent experiments were performed with similar results. Asterisks indicate statistically significant differences according to Student’s t test (**P < 0.01) (Adopted from Chen et al., 2022) 3 Application of PCR and RT-PCR Technology in Virus Detection 3.1 Technical principles and testing process Polymerase chain reaction (PCR) is a technology to amplify specific DNA sequences in vitro. Since most potato viruses are RNA viruses, it is usually necessary to reverse transcription RNA into cDNA by reverse transcription (RT) during detection, and then PCR amplification, that is, RT-PCR. The basic principle is to use a pair of oligonucleotide primers targeting conserved regions of the viral genome to perform multiple rounds of denaturation, annealing and extension cycles on the template cDNA under the action of a thermally stable DNA
RkJQdWJsaXNoZXIy MjQ4ODYzNA==