Root-preferential expression of Newcastle virus glycoproteins driven by NtREL1 promoter in tobacco hairy roots and evaluation of oral delivery in mice.

Newcastle disease virus (NDV) is a lethal virus in avian species with a disastrous effect on the poultry industry. NDV is enveloped by a host-derived membrane with two glycosylated haemagglutinin-neuraminidase (HN) and Fusion (F) proteins. NDV infection usually leads to death within 2-6 days, so the preexisting antibodies provide the most critical protection for this infection. The HN and F glycoproteins are considered the main targets of the immune system. In the present study, two constructs harboring the HN or F epitopes are sub-cloned separately under the control of a root-specific promoter NtREL1 or CaMV35S (35S Cauliflower Mosaic Virus promoter) as a constitutive promoter. The recombinant vectors were transformed into the Agrobacterium tumefaciens strain LBA4404 and then introduced to tobacco (Nicotiana tabacum L.) leaf disk explants. PCR with specific primers was performed to confirm the presence of the hn and f genes in the genome of the regenerated plants. Then, the positive lines were transformed via non-recombinant A. rhizogenes (strain ATCC15834) to develop hairy roots.HN and F were expressed at 0.37% and 0.33% of TSP using the CaMV35S promoter and at 0.75% and 0.54% of TSP using the NtREL1 promoter, respectively. Furthermore, the mice fed transgenic hairy roots showed a high level of antibody responses (IgG and IgA) against rHN and rF proteins.

Computational drug repurposing study of antiviral drugs against main protease, RNA polymerase, and spike proteins of SARS-CoV-2 using molecular docking method.

OBJECTIVES: The new Coronavirus (SARS-CoV-2) created a pandemic in the world in late 2019 and early 2020. Unfortunately, despite the increasing prevalence of the disease, there is no effective drug for the treatment. A computational drug repurposing study would be an appropriate and rapid way to provide an effective drug in the treatment of the coronavirus disease of 2019 (COVID-19) pandemic. In this study, the inhibitory potential of more than 50 antiviral drugs on three important proteins of SARS-CoV-2, was investigated using the molecular docking method. METHODS: By literature review, three important proteins, including main protease, RNA-dependent RNA polymerase (RdRp), and spike, were selected as the drug targets. The three-dimensional (3D) structure of protease, spike, and RdRp proteins was obtained from the Protein Data Bank. Proteins were energy minimized. More than 50 antiviral drugs were considered as candidates for protein inhibition, and their 3D structure was obtained from Drug Bank. Molecular docking settings were defined using Autodock 4.2 software and the algorithm was executed. RESULTS: Based on the estimated binding energy of docking and hydrogen bond analysis and the position of drug binding, five drugs including, indinavir, lopinavir, saquinavir, nelfinavir, and remdesivir, had the highest inhibitory potential for all three proteins. CONCLUSIONS: According to the results, among the mentioned drugs, saquinavir and lopinavir showed the highest inhibitory potential for all three proteins compared to the other drugs. This study suggests that saquinavir and lopinavir could be included in the laboratory phase studies as a two-drug treatment for SARS-CoV-2 inhibition.