Rotavirus non-structural protein 4 usurps host cellular RIPK1-RIPK3 complex to induce MLKL-dependent necroptotic cell death.

The dynamic interface between invading viral pathogens and programmed cell death (PCD) of the host is a finely regulated process. Host cellular demise at the end of the viral life cycle ensures the release of progeny virions to initiate new infection cycles. Rotavirus (RV), a diarrheagenic virus with double-stranded RNA genome, has been reported to trigger different types of PCD such as apoptosis and pyroptosis in a highly regulated way to successfully disseminate progeny virions. Recently our lab also showed that induction of MLKL-driven programmed necroptosis by RV. However, the host cellular machinery involved in RV-induced necroptosis and the upstream viral trigger responsible for it remained unaddressed. In the present study, the signalling upstream of MLKL-driven necroptosis has been delineated where the involvement of Receptor interacting serine/threonine kinase 3 (RIPK3) and 1 (RIPK1) from the host side and RV non-structural protein 4 (NSP4) as the viral trigger for necroptosis has been shown. Interestingly, RV-NSP4 was found to be an integral component of the necrosome complex by interacting with RIPK1, thereby bypassing the requirement of RIPK1 kinase activity. Subsequently, NSP4-driven elevated cytosolic Ca2+ concentration and Ca2+-binding to NSP4 lead further to RHIM domain-dependent RIPK1-RIPK3 interaction, RIPK3-dependent MLKL phosphorylation, and eventual necroptosis. Overall, this study presents the interplay between RV-NSP4 and the host cellular necrosome complex to induce necroptotic death of host cells.

Rotavirus circumvents the antiviral effects of protein ISGylation via proteasomal degradation of Ube1L.

Among the ramified cellular responses elicited in response to pathogenic stimuli, upregulation and covalent conjugation of an Ubiquitin-like modifier ISG15 to lysine residues of target proteins (ISGylation) through sequential action of three enzymes E1 (Ube1L), E2 (Ube2L6) and E3 (Herc5) have emerged as an important regulatory facet governing innate immunity against numerous viral infections. In the present study, we investigated the interplay between host ISGylation system and Rotavirus (RV). We observed that RV infection upregulates the expression of free ISG15 but prevents protein ISGylation. Analysing the expression of ISGylation machinery components revealed that RV infection results in steady depletion of Ube1L protein with the progression of infection. Indeed, restoration of Ube1L expression caused induction in protein ISGylation during RV infection. Subsequent investigation revealed that ectopic expression of RV non-structural protein 5 (NSP5) fosters proteolytic ubiquitylation of Ube1L, thereby depleting it in an ubiquitin-proteasome-dependent manner. Moreover, pan-Cullin inhibition also abrogates proteolytic ubiquitylation and rescued depleted Ube1L in RV-NSP5 expressing cells, suggesting the involvement of host cellular Cullin RING Ligases (CRLs) in proteasomal degradation of Ube1L during RV-SA11 infection. Reciprocal co-immunoprecipitation analyses substantiated a molecular association between Ube1L and RV-NSP5 during infection scenario and also under ectopically overexpressed condition independent of intermediate RNA scaffold and RV-NSP5 hyperphosphorylation. Interestingly, clonal overexpression of Ube1L reduced expression of RV proteins and RV infectivity, which are restored in ISG15 silenced cells, suggesting that Ube1L is a crucial anti-viral host cellular determinant that inhibits RV infection by promoting the formation of ISG15 conjugates.

Actionable loss of SLF2 drives B-cell lymphomagenesis and impairs the DNA damage response.

The DNA damage response (DDR) acts as a barrier to malignant transformation and is often impaired during tumorigenesis. Exploiting the impaired DDR can be a promising therapeutic strategy; however, the mechanisms of inactivation and corresponding biomarkers are incompletely understood. Starting from an unbiased screening approach, we identified the SMC5-SMC6 Complex Localization Factor 2 (SLF2) as a regulator of the DDR and biomarker for a B-cell lymphoma (BCL) patient subgroup with an adverse prognosis. SLF2-deficiency leads to loss of DDR factors including Claspin (CLSPN) and consequently impairs CHK1 activation. In line with this mechanism, genetic deletion of Slf2 drives lymphomagenesis in vivo. Tumor cells lacking SLF2 are characterized by a high level of DNA damage, which leads to alterations of the post-translational SUMOylation pathway as a safeguard. The resulting co-dependency confers synthetic lethality to a clinically applicable SUMOylation inhibitor (SUMOi), and inhibitors of the DDR pathway act highly synergistic with SUMOi. Together, our results identify SLF2 as a DDR regulator and reveal co-targeting of the DDR and SUMOylation as a promising strategy for treating aggressive lymphoma.

SUMOylation inhibition overcomes proteasome inhibitor resistance in multiple myeloma.

Proteasome inhibition is a highly effective treatment for multiple myeloma (MM). However, virtually all patients develop proteasome inhibitor resistance, which is associated with a poor prognosis. Hyperactive small ubiquitin-like modifier (SUMO) signaling is involved in both cancer pathogenesis and cancer progression. A state of increased SUMOylation has been associated with aggressive cancer biology. We found that relapsed/refractory MM is characterized by a SUMO-high state, and high expression of the SUMO E1-activating enzyme (SAE1/UBA2) is associated with poor overall survival. Consistently, continuous treatment of MM cell lines with carfilzomib (CFZ) enhanced SUMO pathway activity. Treatment of MM cell lines with the SUMO E1-activating enzyme inhibitor subasumstat (TAK-981) showed synergy with CFZ in both CFZ-sensitive and CFZ-resistant MM cell lines, irrespective of the TP53 state. Combination therapy was effective in primary MM cells and in 2 murine MM xenograft models. Mechanistically, combination treatment with subasumstat and CFZ enhanced genotoxic and proteotoxic stress, and induced apoptosis was associated with activity of the prolyl isomerase PIN1. In summary, our findings reveal activated SUMOylation as a therapeutic target in MM and point to combined SUMO/proteasome inhibition as a novel and potent strategy for the treatment of proteasome inhibitor-resistant MM.

Sneaking into the viral safe-houses: Implications of host components in regulating integrity and dynamics of rotaviral replication factories.

The biology of the viral life cycle essentially includes two structural and functional entities-the viral genome and protein machinery constituting the viral arsenal and an array of host cellular components which the virus closely associates with-to ensure successful perpetuation. The obligatory requirements of the virus to selectively evade specific host cellular factors while exploiting certain others have been immensely important to provide the platform for designing host-directed antiviral therapeutics. Although the spectrum of host-virus interaction is multifaceted, host factors that particularly influence viral replication have immense therapeutic importance. During lytic proliferation, viruses usually form replication factories which are specialized subcellular structures made up of viral proteins and replicating nucleic acids. These viral niches remain distinct from the rest of the cellular milieu, but they effectively allow spatial proximity to selective host determinants. Here, we will focus on the interaction between the replication compartments of a double stranded RNA virus rotavirus (RV) and the host cellular determinants of infection. RV, a diarrheagenic virus infecting young animals and children, forms replication bodies termed viroplasms within the host cell cytoplasm. Importantly, viroplasms also serve as the site for transcription and early morphogenesis of RVs and are very dynamic in nature. Despite advances in the understanding of RV components that constitute the viroplasmic architecture, knowledge of the contribution of host determinants to viroplasm dynamicity has remained limited. Emerging evidence suggests that selective host determinants are sequestered inside or translocated adjacent to the RV viroplasms. Functional implications of such host cellular reprogramming are also ramifying-disarming the antiviral host determinants and usurping the pro-viral components to facilitate specific stages of the viral life cycle. Here, we will provide a critical update on the wide variety of host cellular pathways that have been reported to regulate the spatial and temporal dynamicity of RV viroplasms. We will also discuss the methods used so far to study the host-viroplasm interactions and emphasize on the potential host factors which can be targeted for therapeutic intervention in the future.

Genetic alterations of the SUMO isopeptidase SENP6 drive lymphomagenesis and genetic instability in diffuse large B-cell lymphoma.

SUMOylation is a post-translational modification of proteins that regulates these proteins' localization, turnover or function. Aberrant SUMOylation is frequently found in cancers but its origin remains elusive. Using a genome-wide transposon mutagenesis screen in a MYC-driven B-cell lymphoma model, we here identify the SUMO isopeptidase (or deconjugase) SENP6 as a tumor suppressor that links unrestricted SUMOylation to tumor development and progression. Notably, SENP6 is recurrently deleted in human lymphomas and SENP6 deficiency results in unrestricted SUMOylation. Mechanistically, SENP6 loss triggers release of DNA repair- and genome maintenance-associated protein complexes from chromatin thereby impairing DNA repair in response to DNA damages and ultimately promoting genomic instability. In line with this hypothesis, SENP6 deficiency drives synthetic lethality to Poly-ADP-Ribose-Polymerase (PARP) inhibition. Together, our results link SENP6 loss to defective genome maintenance and reveal the potential therapeutic application of PARP inhibitors in B-cell lymphoma.

Rotavirus activates MLKL-mediated host cellular necroptosis concomitantly with apoptosis to facilitate dissemination of viral progeny.

Reprogramming the host cellular environment is an obligatory facet of viral pathogens to foster their replication and perpetuation. One of such reprogramming events is the dynamic cross-talk between viruses and host cellular death signaling pathways. Rotaviruses (RVs) have been reported to develop multiple mechanisms to induce apoptotic programmed cell death for maximizing viral spread and pathogenicity. However, the importance of non-apoptotic programmed death events has remained elusive in context of RV infection. Here, we report that RV-induced apoptosis accompanies another non-apoptotic mode of programmed cell death pathway called necroptosis to promote host cellular demise at late phase of infection. Phosphorylation of mixed lineage kinase domain-like (MLKL) protein indicative of necroptosis was observed to concur with caspase-cleavage (apoptotic marker) beyond 6 hr of RV infection. Subsequent studies demonstrated phosphorylated-MLKL to oligomerize and to translocate to plasma membrane in RV infected cells, resulting in loss of plasma membrane integrity and release of alarmin molecules e.g., high mobility group box protein 1 (HMGB1) in the extracellular media. Moreover, inhibiting caspase-cleavage and apoptosis could not fully rescue virus-induced cell death but rather potentiated the necroptotic trigger. Interestingly, preventing both apoptosis and necroptosis by small molecules significantly rescued virus-induced host cytopathy by inhibiting viral dissemination.

A Tale of Usurpation and Subversion: SUMO-Dependent Integrity of Promyelocytic Leukemia Nuclear Bodies at the Crossroad of Infection and Immunity.

Promyelocytic leukemia nuclear bodies (PML NBs) are multi-protein assemblies representing distinct sub-nuclear structures. As phase-separated molecular condensates, PML NBs exhibit liquid droplet-like consistency. A key organizer of the assembly and dynamics of PML NBs is the ubiquitin-like SUMO modification system. SUMO is covalently attached to PML and other core components of PML NBs thereby exhibiting a glue-like function by providing multivalent interactions with proteins containing SUMO interacting motifs (SIMs). PML NBs serve as the catalytic center for nuclear SUMOylation and SUMO-SIM interactions are essential for protein assembly within these structures. Importantly, however, formation of SUMO chains on PML and other PML NB-associated proteins triggers ubiquitylation and proteasomal degradation which coincide with disruption of these nuclear condensates. To date, a plethora of nuclear activities such as transcriptional and post-transcriptional regulation of gene expression, apoptosis, senescence, cell cycle control, DNA damage response, and DNA replication have been associated with PML NBs. Not surprisingly, therefore, SUMO-dependent PML NB integrity has been implicated in regulating many physiological processes including tumor suppression, metabolism, drug-resistance, development, cellular stemness, and anti-pathogen immune response. The interplay between PML NBs and viral infection is multifaceted. As a part of the cellular antiviral defense strategy, PML NB components are crucial restriction factors for many viruses and a mutual positive correlation has been found to exist between PML NBs and the interferon response. Viruses, in turn, have developed counterstrategies for disarming PML NB associated immune defense measures. On the other end of the spectrum, certain viruses are known to usurp specific PML NB components for successful replication and disruption of these sub-nuclear foci has recently been linked to the stimulation rather than curtailment of antiviral gene repertoire. Importantly, the ability of invading virions to manipulate the host SUMO modification machinery is essential for this interplay between PML NB integrity and viruses. Moreover, compelling evidence is emerging in favor of bacterial pathogens to negotiate with the SUMO system thereby modulating PML NB-directed intrinsic and innate immunity. In the current context, we will present an updated account of the dynamic intricacies between cellular PML NBs as the nuclear SUMO modification hotspots and immune regulatory mechanisms in response to viral and bacterial pathogens.

Treading a HOSTile path: Mapping the dynamic landscape of host cell-rotavirus interactions to explore novel host-directed curative dimensions.

Viruses are intracellular pathogens and are dependent on host cellular resources to carry out their cycles of perpetuation. Obtaining an integrative view of host-virus interaction is of utmost importance to understand the complex and dynamic interplay between viral components and host machineries. Besides its obvious scholarly significance, a comprehensive host-virus interaction profile also provides a platform where from host determinants of pro-viral and antiviral importance can be identified and further be subjected to therapeutic intervention. Therefore, adjunct to conventional methods of prophylactic vaccination and virus-directed antivirals, this host-targeted antiviral approach holds promising therapeutic potential. In this review, we present a comprehensive landscape of host cellular reprogramming in response to infection with rotavirus (RV) which causes profuse watery diarrhea in neonates and infants. In addition, an emphasis is given on how host determinants are either usurped or subverted by RV in course of infection and how therapeutic manipulation of specific host factors can effectively modulate the RV life cycle.

Progressive Rotavirus Infection Downregulates Redox-Sensitive Transcription Factor Nrf2 and Nrf2-Driven Transcription Units.

Eukaryotic cells adopt highly tuned stress response physiology under threats of exogenous stressors including viruses to maintain cellular homeostasis. Not surprisingly, avoidance of cellular stress response pathways is an essential facet of virus-induced obligatory host reprogramming to invoke a cellular environment conducive to viral perpetuation. Adaptive cellular responses to oxidative and electrophilic stress are usually taken care of by an antioxidant defense system, core to which lies the redox-responsive transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) and Nrf2-driven transcriptional cascade. Deregulation of host redox balance and redox stress-sensitive Nrf2 antioxidant defense have been reported for many viruses. In the current study, we aimed to study the modulation of the Nrf2-based host cellular redox defense system in response to Rotavirus (RV) infection in vitro. Interestingly, we found that Nrf2 protein levels decline sharply with progression of RV infection beyond an initial upsurge. Moreover, Nrf2 decrease as a whole was found to be accompanied by active nuclear vacuity of Nrf2, resulting in lowered expression of stress-responsive Nrf2 target genes heme oxygenase-1 (HO-1), NAD(P)H quinone dehydrogenase 1, and superoxide dismutase 1 both in the presence and absence of Nrf2-driven transcriptional inducers. Initial induction of Nrf2 concurred with RV-induced early burst of oxidative stress and therefore was sensitive to treatments with antioxidants. Reduction of Nrf2 levels beyond initial hours, however, was found to be independent of the cellular redox status. Furthermore, increasing the half-life of Nrf2 through inhibition of the Kelch-like erythroid cell-derived protein with CNC homology- (ECH-) associated protein 1/Cullin3-RING Box1-based canonical Nrf2 turnover pathway could not restore Nrf2 levels post RV-SA11 infection. Depletion of the Nrf2/HO-1 axis was subsequently found to be sensitive to proteasome inhibition with concurrent observation of increased K48-linked ubiquitination associated with Nrf2. Together, the present study describes robust downregulation of Nrf2-dependent cellular redox defense beyond initial hours of RV infection, justifying our previous observation of potent antirotaviral implications of Nrf2 agonists.

Rotavirus activates a noncanonical ATM-Chk2 branch of DNA damage response during infection to positively regulate viroplasm dynamics.

Surveillance for maintaining genomic pristineness, a protective safeguard of great onco-preventive significance, has been dedicated in eukaryotic cells to a highly conserved and synchronised signalling cascade called DNA damage response (DDR). Not surprisingly, foreign genetic elements like those of viruses are often potential targets of DDR. Viruses have evolved novel ways to subvert this genome vigilance by twisting canonical DDR to a skewed, noncanonical response through selective hijacking of some DDR components while antagonising the others. Though reported for many DNA and a few RNA viruses, potential implications of DDR have not been addressed yet in case of infection with rotavirus (RV), a double-stranded RNA virus. In the present study, we aimed at the modulation of ataxia telangiectasia mutated (ATM)-checkpoint kinase 2 (Chk2) branch of DDR in response to RV infection in vitro. We found activation of the transducer kinase ATM and its downstream effector Chk2 in RV-SA11-infected cells, the activation response being maximal at 6-hr post infection. Moreover, ATM activation was found to be dependent on induction of the upstream sensor Mre11-Rad50-Nbs1 (MRN) complex. Interestingly, RV-SA11-mediated maximal induction of ATM-Chk2 pathway was revealed to be neither preceded by occurrence of nuclear DNA damage nor transduced to formation of damage-induced canonical nuclear foci. Subsequent investigations affirmed sequestration of MRN components as well as ATM-Chk2 proteins away from nucleus into cytosolic RV replication factories (viroplasms). Chemical intervention targeting ATM and Chk2 significantly inhibited fusion and maturation of viroplasms leading to attenuated viral propagation. Cumulatively, the current study describes RV-mediated activation of a noncanonical ATM-Chk2 branch of DDR skewed in favour of facilitated viroplasm fusion and productive viral perpetuation.

Biphasic regulation of RNA interference during rotavirus infection by modulation of Argonaute2.

RNA interference (RNAi) is an evolutionary ancient innate immune response in plants, nematodes, and arthropods providing natural protection against viral infection. Viruses have also gained counter-defensive measures by producing virulence determinants called viral-suppressors-of-RNAi (VSRs). Interestingly, in spite of dominance of interferon-based immunity over RNAi in somatic cells of higher vertebrates, recent reports are accumulating in favour of retention of the antiviral nature of RNAi in mammalian cells. The present study focuses on the modulation of intracellular RNAi during infection with rotavirus (RV), an enteric virus with double-stranded RNA genome. Intriguingly, a time point-dependent bimodal regulation of RNAi was observed in RV-infected cells, where short interfering RNA (siRNA)-based RNAi was rendered non-functional during early hours of infection only to be reinstated fully beyond that early infection stage. Subsequent investigations revealed RV nonstructural protein 1 to serve as a putative VSR by associating with and triggering degradation of Argonaute2 (AGO2), the prime effector of siRNA-mediated RNAi, via ubiquitin-proteasome pathway. The proviral significance of AGO2 degradation was further confirmed when ectopic overexpression of AGO2 significantly reduced RV infection. Cumulatively, the current study presents a unique modulation of host RNAi during RV infection, highlighting the importance of antiviral RNAi in mammalian cells.

Synchronized Orchestration of miR-99b and let-7g Positively Regulates Rotavirus Infection by Modulating Autophagy.

Rotavirus (RV), the major etiological agent of viral gastroenteritis in young children, kills over 200 thousand infants each year. In spite of available vaccines, rotaviral diarrhoea is still a major problem in developing countries of Asia and Africa. Therefore, the studies on RV infection and host antiviral responses are warranted. The active correlation between virus infection and activation of autophagy machinery and positive influence of autophagy on RV replication have been documented recently. Previous study from our group showed dysregulation of several cellular miRNAs during RV infection, though their significance remained largely unknown. Since cellular microRNAs (miRNAs) have been implicated in the control of several fundamental biological processes including stress response and autophagy, we focused on two miRNAs, miR-99b and let-7g, and analyzed their function to gain insight into the miRNA-autophagy crosstalk during RV infection. This study shows that RV suppresses let-7g expression but enhances miR-99b that in turn augment major autophagy regulators. Ectopic expression of let-7g and knockdown of miR-99b resulted in inhibition of autophagy, hence, reduction of RV replication. Overall, our study highlights new mechanistic insights for understanding the role of miRNAs in modulating RV infection and possibility of using RNA interference as an antiviral therapeutic target.

RA-839, a selective agonist of Nrf2/ARE pathway, exerts potent anti-rotaviral efficacy in vitro.

Acute watery diarrhea due to Rotavirus (RV) infection is associated with high infantile morbidity and mortality in countries with compromised socio-economic backgrounds. Although showing promising trends in developed countries, the efficacy of currently licensed RV vaccines is sub-optimal in socio-economically poor settings with high disease burden. Currently, there are no approved anti-rotaviral drugs adjunct to classical vaccination program. Interestingly, dissecting host-rotavirus interaction has yielded novel, non-mutable host determinants which can be subjected to interventions by selective small molecules. The present study was undertaken to evaluate the anti-RV potential of RA-839, a recently discovered small molecule with potent and highly selective agonistic activity towards cellular redox stress-sensitive Nuclear factor erytheroid-derived-2-like 2 (Nrf2)/Antioxidant Response Element (ARE) pathway. In vitro studies revealed that RA-839 inhibits RV RNA and protein expression, viroplasm formation, yield of virion progeny and virus-induced cytopathy independent of RV strains, RV-permissive cell lines and without bystander cytotoxicity. Anti-RV potency of RA-839 was subsequently identified to be independent of stochastic Interferon (IFN) stimulation but to be dependent on RA-839's ability to stimulate Nrf2/ARE signaling. Interestingly, anti-rotaviral effects of RA-839 were also mimicked by 2-Cyano-3, 12-dioxo-oleana-1, 9(11)-dien-28-oic acid methyl ester (CDDO-Me) and Hemin, two classical pharmacological activators of Nrf2/ARE pathway. Overall, this study highlights that RA-839 is a potent antagonist of RV propagation in vitro and can be developed as anti-rotaviral therapeutics.

Rotaviral nonstructural protein 4 triggers dynamin-related protein 1-dependent mitochondrial fragmentation during infection.

Dynamic equilibrium between mitochondrial fission and mitochondrial fusion serves as an important quality control system within cells ensuring cellular vitality and homeostasis. Viruses often target mitochondrial dynamics as a part of their obligatory cellular reprogramming. The present study was undertaken to assess the status and regulation of mitochondrial dynamics during rotavirus infection. Distinct fragmentation of mitochondrial syncytia was observed during late hours of RV (SA11, Wa, A5-13) infection. RV nonstructural protein 4 (NSP4) was identified as the viral trigger for disrupted mitochondrial morphology. Severance of mitochondrial interconnections was found to be a dynamin-related protein 1 (Drp1)-dependent process resulting synergistically from augmented mitochondrial fission and attenuated mitochondrial fusion. Cyclin-dependent kinase 1 was subsequently identified as the cellular kinase responsible for fission-active Ser616 phosphorylation of Drp1. In addition to its positive role in mitochondrial fission, Drp1 also resulted in mitochondrial translocation of E3-ubiquitin ligase Parkin leading to degradation of mitochondrial fusion protein Mitofusin 1. Interestingly, RV-NSP4 was found to interact with and be involved in recruiting fission-active pool of Serine 616 phosphoDrp1 (Ser616 pDrp1) to mitochondria independent of accessory adaptors Mitochondrial fission factor and Fission protein 1 (Fis1). Inhibition of either Drp1 or Ser616 pDrp1 resulted in significant decrease in RV-NSP4-induced intrinsic apoptotic pathway. Overall, this study underscores an efficient strategy utilised by RV to couple apoptosis to mitochondrial fission facilitating dissemination of viral progeny.

Tyrosine phosphorylation modulates mitochondrial chaperonin Hsp60 and delays rotavirus NSP4-mediated apoptotic signaling in host cells.

Phosphoproteomics-based platforms have been widely used to identify post translational dynamics of cellular proteins in response to viral infection. The present study was undertaken to assess differential tyrosine phosphorylation during early hours of rotavirus (RV) SA11 infection. Heat shock proteins (Hsp60) were found to be enriched in the data set of RV-SA11 induced differentially tyrosine-phosphorylated proteins at 2 hr post infection (hpi). Hsp60 was further found to be phosphorylated by an activated form of Src kinase on 227th tyrosine residue, and tyrosine phosphorylation of mitochondrial chaperonin Hsp60 correlated with its proteasomal degradation at 2-2.5hpi. Interestingly, mitochondrial Hsp60 positively influenced translocation of the rotaviral nonstructural protein 4 to mitochondria during RV infections. Phosphorylation and subsequent transient degradation of mitochondrial Hsp60 during early hours of RV-SA11 infection resulted in inhibition of premature import of nonstructural protein 4 into mitochondria, thereby delaying early apoptosis. Overall, the study highlighted one of the many strategies rotavirus undertakes to prevent early apoptosis and subsequent reduced viral progeny yield.

Rotavirus disrupts cytoplasmic P bodies during infection.

Cytoplasmic Processing bodies (P bodies), the RNA-protein aggregation foci of translationally stalled and potentially decaying mRNA, have been reported to be differentially modulated by viruses. Rotavirus, the causative agent of acute infantile gastroenteritis is a double stranded RNA virus which completes its entire life-cycle exclusively in host cell cytoplasm. In this study, the fate of P bodies was investigated upon rotavirus infection. It was found that P bodies get disrupted during rotavirus infection. The disruption occurred by more than one different mechanism where deadenylating P body component Pan3 was degraded by rotavirus NSP1 and exonuclease XRN1 along with the decapping enzyme hDCP1a were relocalized from cytoplasm to nucleus. Overall the study highlights decay and subcellular relocalization of P body components as novel mechanisms by which rotavirus subverts cellular antiviral responses.