Project description:One goal of viral infection is to reprogram the host cell to optimize viral replication. As part of this process, viral miRNAs may compete for components of the miRNA/siRNA pathway as well as regulate cellular targets. Mouse Cytomegalovirus has been described to generate large numbers of viral miRNAs during lytic infection and was therefore used to analyze the impact of viral miRNAs on the host cell small RNA system as well as to check for sorting of viral small RNAs into specific Ago-proteins. Deep sequencing analysis of MCMV infected cells revealed that viral miRNAs represent only app. 13% of all detected miRNAs. All previously described MCMV miRNAs with the exception of miR-m88-1* were confirmed and for the MCMV miR-m01-1 hairpin an additional miRNA, designated miR-m01-1-3p, was found. Its presence was confirmed by qPCR and Northern Blot. Deep sequencing after RISC IP with antibodies specific for either Ago1 or Ago2 showed that all MCMV miRNAs are loaded into both RISC complexes. The ratio of MCMV to mouse miRNAs was not increased after immunoprecipitation of Ago-proteins. Viral miRNAs therefore do not overwhelm the host miRNA processing system nor are they preferentially incorporated into RISC. We found that 3 mouse miRNAs showed an altered expression due to MCMV infection. Down-regulation of miR-27a, as previously described, could be confirmed. In addition, miR-26a was down-regulated and an up-regulation of miR-7a dependent on viral protein expression could be observed. Examination of small RNA expression in uninfected vs. infected cells, immunoprecipitation + sequencing of Ago1 and Ago2 loaded small RNAs in infected cells
Project description:One goal of viral infection is to reprogram the host cell to optimize viral replication. As part of this process, viral miRNAs may compete for components of the miRNA/siRNA pathway as well as regulate cellular targets. Mouse Cytomegalovirus has been described to generate large numbers of viral miRNAs during lytic infection and was therefore used to analyze the impact of viral miRNAs on the host cell small RNA system as well as to check for sorting of viral small RNAs into specific Ago-proteins. Deep sequencing analysis of MCMV infected cells revealed that viral miRNAs represent only app. 13% of all detected miRNAs. All previously described MCMV miRNAs with the exception of miR-m88-1* were confirmed and for the MCMV miR-m01-1 hairpin an additional miRNA, designated miR-m01-1-3p, was found. Its presence was confirmed by qPCR and Northern Blot. Deep sequencing after RISC IP with antibodies specific for either Ago1 or Ago2 showed that all MCMV miRNAs are loaded into both RISC complexes. The ratio of MCMV to mouse miRNAs was not increased after immunoprecipitation of Ago-proteins. Viral miRNAs therefore do not overwhelm the host miRNA processing system nor are they preferentially incorporated into RISC. We found that 3 mouse miRNAs showed an altered expression due to MCMV infection. Down-regulation of miR-27a, as previously described, could be confirmed. In addition, miR-26a was down-regulated and an up-regulation of miR-7a dependent on viral protein expression could be observed.
Project description:Ly49G2+ NK cells mediate essential control of murine cytomegalovirus (MCMV) infection in mice which express the H-2Dk class I molecule. As a cognate ligand for specific Ly49G2 inhibitory receptor allotypes, H-2Dk also licenses Ly49G2+ NK cells in naïve and MCMV-infected mice. These findings suggest Ly49G2 may promote antiviral NK cell activities during MCMV infection. Indeed, in mice lacking the Ly49G2 receptor, MCMV resistance is fully abrogated. Additionally, NK cells expressing Ly49R, an NK cell associated activation receptor that also recognizes H-2Dk, have their function augmented by Ly49G2 and are required for MCMV resistance.
Project description:Reactivation of latent HCMV is a significant infectious complication of organ transplantation, and current therapies target viral replication once reactivation of transcriptionally silent, latent virus has already occurred. The specific molecular pathways that activate viral gene expression are not well understood. Our studies aim to identify these factors, with the goal of developing novel therapies that prevent transcriptional reactivation in transplant recipients. MCMV is a valuable model for studying latency and reactivation of CMV induced by organ transplantation. We previously demonstrated that transplantation of MCMV-latently infected kidneys into allogeneic recipients induces transcriptional reactivation of immediate early (IE) gene expression within 48 hr. We used microarrays to profile global mouse kidney gene expression associated with transcriptional reactivation of MCMV immediate early gene expression at 48 hr after transplant of MCMV latently infected kidneys into allogeneic recipients. We identified differentially expressed genes and pathways associated with both early acute rejection and reactivation of MCMV. control vs. allograft
Project description:We aimed to elucidate biological function of A Disintegrin and Metalloprotease (Adm) A and AdmB in Aspergillus oryzae. To observe influences of admA and admB deletions, each gene deletion strain was analyzed by RNA-Seq. mRNA of Deletion-control, ∆admA∆admB, ∆admA and ∆admB cultivated in wheat bran solid culture were sequenced, in quintuplicate, using Illumina GAIIx.
Project description:Reactivation of latent HCMV is a significant infectious complication of organ transplantation, and current therapies target viral replication once reactivation of transcriptionally silent, latent virus has already occurred. The specific molecular pathways that activate viral gene expression are not well understood. Our studies aim to identify these factors, with the goal of developing novel therapies that prevent transcriptional reactivation in transplant recipients. MCMV is a valuable model for studying latency and reactivation of CMV induced by organ transplantation. We previously demonstrated that transplantation of MCMV-latently infected kidneys into allogeneic recipients induces transcriptional reactivation of immediate early (IE) gene expression within 48 hr. We used microarrays to profile global mouse kidney gene expression associated with transcriptional reactivation of MCMV immediate early gene expression at 48 hr after transplant of MCMV latently infected kidneys into allogeneic recipients. We identified differentially expressed genes and pathways associated with both early acute rejection and reactivation of MCMV.
Project description:Innate and adaptive immune cells can acquire “memory” of encounters with a diverse range of activating signals to tune their response to secondary stimuli. Group 1 innate lymphoid cells (ILC1) are recently discovered tissue-resident sentinels that are essential for early host protection from intracellular pathogens at initial sites of infection. However, whether ILC1 function as short-lived effectors or persist and refine their responsiveness following pathogen challenge is not well understood. Furthermore, whether pathogen-derived antigens directly modulate tissue-resident ILC responses remains unclear. Here, we found that liver-resident ILC1 expand locally and persist following the resolution of mouse cytomegalovirus (MCMV) infection. MCMVexperienced ILC1 acquired stable transcriptional, epigenetic, and phenotypic changes, with an enhanced protective effector response to secondary MCMV challenge. Protective memory ILC1 responses were dependent on the MCMV-encoded glycoprotein m12, but not formed during bystander cytokine activation following heterologous infection. Thus, liver ILC1 acquire adaptive features in a MCMV-specific manner.
Project description:Recent work indicates that salivary glands are able to constitutively recruit CD8+ T cells and retain them as tissue resident memory T cells (TRM), independently of local infection, inflammation or antigen. To understand the mechanisms supporting T cell recruitment to the salivary gland, we compared T cell migration to the salivary gland in mice infected or not with murine cytomegalovirus (MCMV), a herpesvirus that infects the salivary gland and promotes the accumulation of salivary gland TRM. We found that acute MCMV infection increased rapid T cell recruitment to the salivary gland, but that equal numbers of activated CD8+ 44 T cells eventually accumulated in both infected and uninfected glands. T cell recruitment to uninfected salivary glands depended on chemokines and the integrin α4. Several chemokines were expressed in the salivary glands of both infected and uninfected mice and many of these could promote the migration of MCMV-specific T cells in vitro. MCMV infection increased expression of chemokines that interact with the receptors CXCR3 and CCR5, but neither receptor was needed for T cell recruitment to the salivary gland during MCMV infection. Unexpectedly however, the chemokine receptor CXCR3 was critical for T cell accumulation in uninfected salivary glands. Together, these data suggest that CXCR3 and the integrin α4 mediate T cell recruitment to uninfected salivary glands, but that redundant mechanisms mediate T cell recruitment after MCMV infection.
Project description:Swiss murine embryonic fibroblasts (NIH-3T3) were infected with wild-type Smith strain mouse cytomegalovirus (MCMV) at a multiplicity of infection (MOI) of 10. Sequencing libraries were prepared using the cRNA-seq protocol from the indicated time points of infection as described by Whisnant A.W. et al, Nat. Commun (2020)
Project description:MCMV has been reported to infect neural stem cells in the subventricular zone. These same cells have been shown to give rise to gliomas. We wanted to test expression levels of RNA in this cell population after MCMV infection in a mouse model of glioma.