Significance Viral outbreaks can be sudden and result in devastating social economic consequences. Chikungunya virus (CHIKV) of rash, arthritis, neurologic disease have occurred Africa, Asia, Europe, the Americas. There are no licensed vaccines to prevent or drugs treat CHIKV infection, mechanisms generation poorly understood. Here, we identify a macrodomain-containing protein with enzymatic ADP-ribosylhydrolase activity that is critical for virulence mammals define substrate specificity...

Alphaviruses are plus-strand RNA viruses that cause encephalitis, rash, and arthritis. The nonstructural protein (nsP) precursor polyprotein is translated from genomic processed into four nsPs. nsP3 has a highly conserved macrodomain (MD) binds ADP-ribose (ADPr), which can be conjugated to as posttranslational modification involving transfer of ADPr NAD+ by poly polymerases (PARPs). nsP3MD also removes mono ADP-ribosylated (MARylated) substrates. To determine aspects alphavirus replication...

Significance Alphaviruses are mosquito-borne RNA viruses that cause rash, arthritis, and neurologic disease. Despite a continued risk of outbreaks, there no licensed interventions for any alphavirus. For progress in control, an understanding the molecular targets affect virus replication virulence is essential. This paper characterizes conserved macrodomain factor nonstructural protein 3 (nsP3). We discovered ADP-ribosylhydrolase activity critical controlling composition cellular...

Abstract Zika virus (ZIKV) infection in pregnant women has been established as a cause of microcephaly newborns. Here we test the hypothesis that neurodevelopmental stages when brain is undergoing rapid growth are particularly vulnerable to effects ZIKV infection. We injected intracranially into wild type C57BL/6 mice at two different time points: early postnatal development, growing its maximal rate, and weaning, largely reached adult size. Both points showed widespread immunoreactivity for...

Macrodomain (MD), a highly conserved protein fold present in subset of plus-strand RNA viruses, binds to and hydrolyzes ADP-ribose (ADPr) from ADP-ribosylated proteins. ADPr-binding by the alphavirus nonstructural 3 (nsP3) MD is necessary for initiation virus replication neural cells, whereas hydrolase activity facilitates complex amplification. To determine importance these activities pathogenesis encephalomyelitis, mutations were introduced into nsP3 Sindbis (SINV), effects on ADPr binding...

Abstract Chikungunya virus (CHIKV), an arthritogenic alphavirus, is transmitted to humans by infected Aedes (Ae.) aegypti and Ae.albopictus mosquitoes. In the study, reverse-transcription PCR (RT PCR) isolation detected CHIKV in patient samples also adult mosquitoes that was derived from larvae collected during a chikungunya (CHIK) outbreak Kerala 2009. The strains involved were East, Central South African (ECSA) genotype had E1 A226V mutation. viral CHIK patients same area showed close...

Chikungunya virus (CHIKV), an arthritogenic old-world alphavirus, has been implicated in the central nervous system (CNS) infection infants and elderly patients. Astrocytes are major immune cells of brain parenchyma that mediate inflammation. In present study we found a local isolate CHIKV infect activate U-87 MG cells, glioblastoma cell line human astrocyte origin. The kinetics were similar infected embryo kidney (HEK293) as indicated by immunofluorescence plaque assays, 24h post-infection...

Abstract Biomolecular condensates are cellular compartments without enveloping membranes, enabling them to dynamically adjust their composition in response environmental changes through post-translational modifications. Recent work has revealed that interferon-induced ADP-ribosylation (ADPr), which can be reversed by a SARS-CoV-2-encoded hydrolase, is enriched within condensate. However, the identity of condensate and responsible host ADP-ribosyltransferase remain elusive. Here, we...

Susceptibility to alphavirus encephalomyelitis is dependent on a variety of factors, including the genetic background host. Neuroadapted Sindbis virus (NSV) causes uniformly fatal disease in adult C57BL/6 (B6) mice, but BALB/c (Bc) mice recover from infection. In B6 immune mediated rather than direct result To identify immunological determinants host susceptibility NSV-induced encephalomyelitis, we compared titers and responses Bc infected intranasally with NSV. had higher levels...

Abstract Zika virus (ZIKV) is a re-emerged flavivirus transmitted by Aedes spp mosquitoes that has caused outbreaks of fever and rash on islands in the Pacific Americas. These have been associated with neurologic complications include congenital abnormalities Guillain-Barré syndrome (GBS). The pathogenesis ZIKV-associated GBS, potentially life-threatening peripheral nerve disease, remains unclear. Because Schwann cells (SCs) play central role function can be target for damage we...

COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had a devastating impact on global public health, emphasizing the importance of understanding innate immune mechanisms and cellular restriction factors that cells can harness to fight viral infections. The multimembrane-spanning zinc metalloprotease ZMPSTE24 is one such factor. well-characterized proteolytic role in maturation prelamin A, precursor nuclear scaffold protein lamin A. An apparently...

Chikungunya virus (CHIKV), a positive-stranded RNA virus, can cause neurological complications by infecting the major parenchymal cells of brain such as neurons and astrocytes. A proteomic analysis CHIKV-infected human astrocytic cell line U-87 MG revealed tight functional associations among modulated proteins. The predominant cellular pathways involved were transcription–translation machinery, cytoskeletol reorganization, apoptosis, ubiquitination, metabolism. In proteome, we could also...

ABSTRACT Biomolecular condensates are cellular compartments without enveloping membranes, enabling them to dynamically adjust their composition in response environmental changes through post-translational modifications. A recent study has revealed that interferon-induced ADP-ribosylation (ADPr), which can be reversed by a SARS-CoV-2-encoded hydrolase, is enriched within condensate. However, the identity of condensate and responsible host ADP-ribosyltransferase remain elusive. Here, we...

The 5' capped, message-sense RNA genome of Chikungunya virus (CHIKV) utilizes the host cell machinery for translation. Translation is regulated by eIF2 alpha at initiation phase and eIF4F cap recognition. Translational suppression phosphorylation occurs as an early event in many alphavirus infections. We observe that CHIKV-infected HEK293 cells, this a late event, which time viral replication has reached exponential phase, implying its minimal role restriction. regulation mediated through...

: Innate immunity is the first line of defence elicited by host immune system to fight against invading pathogens such as viruses and bacteria. From this elementary response, more complex antigen-specific adaptive responses are recruited provide a long-lasting memory pathogens. gets activated when cell utilizes diverse set receptors known pattern recognition (PRR) recognize that have penetrated respond with cellular processes like complement system, phagocytosis, cytokine release...

Chikungunya virus (CHIKV) causes outbreaks of rash, arthritis, and fever associated with neurologic complications, where astrocytes are preferentially infected. A determinant virulence is the macrodomain (MD) nonstructural protein 3 (nsP3), which binds removes ADP-ribose (ADPr) from ADP-ribosylated substrates regulates stress-granule disruption. We compared replication CHIKV 181/25 (WT) MD mutants decreased ADPr binding hydrolase (G32S) or increased (Y114A) activities in C8-D1A astrocytic...

ABSTRACT Zinc finger antiviral protein (ZAP), also known as PARP13, is an factor effective against several virus families. ZAP contains three major domains: N-terminal zinc fingers, central WWE domains, and a C-terminal inactive ADP-ribosyltransferase domain, which present only in the longer isoform ZAPL. While both domains inhibit viral replication, role of remains unclear. bind poly(ADP-ribose) (PAR). In this study, we focus on ZAPS, shorter comprised minimal unit that confers activity...

Chikungunya virus (CHIKV) is an emerging, mosquito-borne arthritic alphavirus increasingly associated with severe neurological sequelae and long-term morbidity. However, there limited understanding of the crucial host components involved in CHIKV replicase assembly complex formation, thus replication virulence-determining factors, within central nervous system (CNS). Furthermore, majority CNS studies focus on neuronal infection, even though astrocytes represent main cerebral target....

Chikungunya virus (CHIKV) re-emergence in the last decade has resulted explosive epidemics. Along with classical symptoms of fever and debilitating arthralgia, there were occurrences unusual clinical presentations such as neurovirulence mortality. These generated a renewed global interest to develop prophylactic vaccines. Here, using approach attenuation, we developed an attenuated CHIKV strain (RGCB355/KL08-p75) for purpose. Repeated passaging (75 times) local isolate ECSA lineage U-87 MG...