Inhibitor of Sarco/Endoplasmic Reticulum Calcium-ATPase Impairs Multiple Steps of Paramyxovirus Replication

Abstract

Sarco/endoplasmic reticulum calcium-ATPase (SERCA) is a membrane-bound cytosolic enzyme which is known to regulate the uptake of calcium into the sarco/endoplasmic reticulum. Herein, we demonstrate for the first time that SERCA can also regulate virus replication. Treatment of Vero cells with SERCA-specific inhibitor (Thapsigargin) at a concentration that is nontoxic to the cells significantly reduced Peste des petits ruminants virus (PPRV) and Newcastle disease virus (NDV) replication. Conversely, overexpression of SERCA rescued the inhibitory effect of Thapsigargin on virus replication. PPRV and NDV infection induced SERCA expression in Vero cells, which could be blocked by Thapsigargin. Besides inducing enhanced formation of cytoplasmic foci, Thapsigargin was shown to block viral entry into the target cells as well as synthesis of viral proteins. Furthermore, NDV was shown to acquire significant resistance to Thapsigargin upon long-term passage (P) in Vero cells. As compared to the P0 and P70-Control, the fusion (F) protein of P70-Thapsigargin virus exhibited a unique mutation at amino acid residue 104 (E104K), whereas no Thapsigargin-associated mutations were observed in HN gene. To the best of our knowledge, this is the first report describing the virus-supportive role of SERCA and a rare report suggesting that viruses may acquire resistance even in the presence of an inhibitor that targets a cellular factor.

Isolation and characterization of lumpy skin disease virus from cattle in India

“…Plaque was performed as per the previously described methods along with some modifications [17,20]. The confluent monolayers of Vero cells, grown in 6 well tissue culture plates, were infected with 10-fold serial dilutions of virus for 1 h at 37 o C, after which the infecting medium was replaced with an agar-overlay containing equal volume of 2X L-15 medium and 1% agar.…”

Marantodes pumilum (Blume) Kuntze (Kacip Fatimah) stimulates uterine contraction in rats in post-partum period

“…Inhibitors to uterotonin receptors such as atropine (MAChR blocker) (Lochner and Thompson, 2016), atosiban (oxytocin receptor blocker) (Abdullahi et al, 2018) and piprant (PG receptor antagonist) (Kirkby Shaw et al, 2016) could be used to confirm the involvement of these uterotonins in inducing myometrial contraction. In the meantime, thapsigargin, a specific inhibitor for SERCA (Kumar et al, 2019), DY-9836, a specific inhibitor for calmodulin (Wang et al, 2017) and ML-7 and ML-9 (specific MLCK inhibitors) could be used to confirm the involvement of these proteins in regulating myometrial contraction during the post-partum period. Xestospongin B, a competitive inhibitor of IP3K-mediated Ca 2+ signalling could be used to confirm the involvement of IP3K in MPE-mediated effect in the uterus in the period post-partum (Jaimovich et al, 2005).…”

Isolation and characterization of bovine herpes virus 5 (BHV5) from cattle in India

“…Plaque assay was performed as per previously described methods along with some modifications [28,29]. The confluent monolayers of MDBK cells, grown in 6 well tissue culture plates, were infected with 10-fold serial dilutions of virus for 1 h at 37°C, after which the infecting medium was replaced with an agar-overlay containing equal volume of 2X L-15 medium and 2% agar.…”