Manjunath Siddappa

Dr. Manjunath Siddappa


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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24 February 2015 in Veterinary Research
Verified
Journal Article
Open access
PDF file
MSManjunath Siddappa
Manjunath Siddappa
RGRavi K Gandham
Ravi K Gandham
BMBishnu Prasad Mishra
Bishnu Prasad Mishra
BMBina Mishra
Bina Mishra
ASAditya Prasad Sahoo
Aditya Prasad Sahoo
Sarath Chandra JangaSarath Chandra Janga
Sarath Chandra Janga
Peste des petits ruminants (PPR), is an acute transboundary viral disease of economic importance, affecting goats and sheep. Mass vaccination programs around the world resulted in the decline of PPR outbreaks. Sungri 96 is a live attenuated vaccine, widely used in Northern India against PPR. This vaccine virus, isolated from goat works efficiently both in sheep and goat. Global gene expression changes under PPR vaccine virus infection are not yet well defined. Therefore, in this study we investigated the host-vaccine virus interactions by infecting the peripheral blood mononuclear cells isolated from goat with PPRV (Sungri 96 vaccine virus), to quantify the global changes in the transcriptomic signature by RNA-sequencing. Viral genome of Sungri 96 vaccine virus was assembled from the PPRV infected transcriptome confirming the infection and demonstrating the feasibility of building a complete non-host genome from the blood transcriptome. Comparison of infected transcriptome with control transcriptome revealed 985 differentially expressed genes. Functional analysis showed enrichment of immune regulatory pathways under PPRV infection. Key genes involved in immune system regulation, spliceosomal and apoptotic pathways were identified to be dysregulated. Network analysis revealed that the protein - protein interaction network among differentially expressed genes is significantly disrupted in infected state. Several genes encoding TFs that govern immune regulatory pathways were identified to co-regulate the differentially expressed genes. These data provide insights into the host - PPRV vaccine virus interactome for the first time. Our findings suggested dysregulation of immune regulatory pathways and genes encoding Transcription Factors (TFs) that govern these pathways in response to viral infection.

1 February 2017 in Virus Research
Verified
Journal Article
Closed access
MSManjunath Siddappa
Manjunath Siddappa
BMBishnu Prasad Mishra
Bishnu Prasad Mishra
BMBina Mishra
Bina Mishra
ASAditya Prasad Sahoo
Aditya Prasad Sahoo
ATAshok K. Tiwari
Ashok K. Tiwari
Sarath Chandra JangaSarath Chandra Janga
Sarath Chandra Janga

1 March 2017 in Genomics Data
Verified
Journal Article
Open access
ASAnjali Singh
Anjali Singh
MPMinakshi Prasad
Minakshi Prasad
BMBina Mishra
Bina Mishra
MSManjunath Siddappa
Manjunath Siddappa
ASAmit Ranjan Sahu
Amit Ranjan Sahu
RGRavi K Gandham
Ravi K Gandham
Bluetongue is an economically important infectious, arthropod borne viral disease of domestic and wild ruminants, caused by Bluetongue virus (BTV). Sheep are considered the most susceptible hosts, while cattle, buffalo and goats serve as reservoirs. The viral pathogenesis of BTV resulting in presence or absence of clinical disease among different hosts is not clearly understood. In the present study, transcriptome of sheep and goats peripheral blood mononuclear cells infected with BTV-16 was explored. The differentially expressed genes (DEGs) identified were found to be significantly enriched for immune system processes - NFκB signaling, MAPK signaling, Ras signaling, NOD signaling, RIG signaling, TNF signaling, TLR signaling, JAK-STAT signaling and VEGF signaling pathways. Greater numbers of DEGs were found to be involved in immune system processes in goats than in sheep. Interestingly, the DEHC (differentially expressed highly connected) gene network was found to be dense in goats than in sheep. Majority of the DEHC genes in the network were upregulated in goats but down-regulated in sheep. The network of differentially expressed immune genes with the other genes further confirmed these findings. Interferon stimulated genes - IFIT1 (ISG56), IFIT2 (ISG54) and IFIT3 (ISG60) responsible for antiviral state in the host were found to be upregulated in both the species. STAT2 was the TF commonly identified to co-regulate the DEGs, with its network showing genes that are downregulated in sheep but upregulated in goats. The genes dysregulated and the networks perturbed in the present study indicate host variability with a positive shift in immune response to BTV in goats than in sheep.

24 May 2024 in Viruses
Verified
Journal Article
Open access
PDF file
MTMegolhubino Terhuja
Megolhubino Terhuja
MSManjunath Siddappa
Manjunath Siddappa
PLPramila Lamichhane
Pramila Lamichhane
CMChetan Meshram
Chetan Meshram
TSTimothy Allen Snider
Timothy Allen Snider
AOAntonius Oomens
Antonius Oomens
Respiratory syncytial virus (RSV) is a major cause of severe respiratory tract disease worldwide, and a pediatric vaccine is not available. We generated a filamentous RSV-based virus-like particle (VLP) that presents the central conserved region of the attachment protein G. This was achieved by co-expressing the matrix protein, phosphoprotein, nucleoprotein, and a hybrid fusion protein in which the F ectodomain was replaced with the G central region (GCR). The latter is relatively conserved and contains a receptor binding site and hence is a logical vaccine target. The immunogenicity and efficacy of the resulting VLP, termed VLP-GCR, were examined in mice using intranasal application without adjuvant. VLP-GCR induced substantial anti-N antibody levels but very low anti-G antibody levels, even after three vaccinations. In contrast, a VLP presenting prefusion-stabilized fusion (preF) protein instead of GCR induced both high anti-F and anti-nucleoprotein antibody levels, suggesting that our GCR antigen was poorly immunogenic. Challenge of VLP-GCR-vaccinated mice caused increased weight loss and lung pathology, and both VLPs induced mucus in the lungs. Thus, neither VLP is suitable as a vaccine for RSV-naive individuals. However, VLP-preF enhanced the proportion of preF antibodies and could serve as a multi-antigen mucosal booster vaccine in the RSV-experienced population.

14 May 2020 in bioRxiv
Verified
Preprint
Open access
PDF file
MSManjunath Siddappa
Manjunath Siddappa
SWSajad A. Wani
Sajad A. Wani
MLMark Long
Mark Long
DLDamien Leach
Damien Leach
Ewy MathéEwy Mathé
Ewy Mathé
MCMoray Campbell
Moray Campbell
Defining altered transcription factor (TF) and coregulators that are oncogenic drivers remains a challenge, in part because of the multitude of TFs and coregulators. We addressed this challenge by using bootstrap approaches to test how expression, copy number alterations or mutation of TFs (n = 2662), coactivators (COA; n= 766); corepressor (COR; n = 599); mixed function coregulators (MIXED; n = 511) varied across seven prostate cancer (PCa) cohorts (three of localized and four advanced disease). COAS, CORS, MIXED and TFs all displayed significant down-regulated expression (q.value < 0.1) and correlated with protein expression (ρ 0.4 to 0.55). Stringent expression filtering identified commonly altered TFs and coregulators including well-established (e.g. ERG) and underexplored (e.g. PPARGC1A , encodes PGC1α) in localized PCa. Reduced PPARGC1A expression significantly associated with worse disease-free survival in two cohorts of localized PCa. Stable PGC1α knockdown in LNCaP cells increased growth rates and invasiveness and RNA-Seq revealed a profound basal impact on gene expression (~2300 genes; FDR < 0.05, logFC > 1.5), but only modestly impacted PPARγ responses. GSEA analyses of the PGC1α transcriptome revealed that it significantly altered the AR-dependent transcriptome, and was enriched for epigenetic modifiers. PGC1α-dependent genes were overlapped with PGC1α-ChIP-Seq genes and significantly associated in TCGA with higher grade tumors and worse disease-free survival. Together these data demonstrate an approach to identify cancer-driver coregulators in cancer and that PGC1α expression is clinically significant yet underexplored coregulator in aggressive early stage PCa.