Project description:Retinal ganglion cell (RGC) death is the final consequence of many blinding diseases, where there is considerable variation in the time course and severity of RGC loss. Indeed, this process appears to be influenced by a wide variety of genetic and environmental factors. In this study we explored the genetic basis for differences in ganglion cell death in two inbred strains of mice. We found that RGCs are more susceptible to death following optic nerve crush in C57BL/6J mice (54% survival) than in DBA2/J mice (62% survival). Using the Illumina Mouse-6 microarray, we identified 1,580 genes with significant change in expression following optic nerve crush in these two strains of mice. Our analysis of the changes occurring after optic nerve crush demonstrated that the greatest amount of change (44% of the variance) was due to the injury itself. This included changes associated with ganglion cell death, reactive gliosis, and abortive regeneration. The second pattern of gene changes (23% of the variance) was primarily related to differences in gene expressions observed between the C57BL/6J and DBA/2J mouse strains. The remaining changes in gene expression represent interactions between the effects of optic nerve crush and the genetic background of the mouse. We extracted one genetic network from this dataset that appears to be related to tissue remodeling. One of the most intriguing sets of changes included members of the crystallin family of genes, which may represent a signature of pathways modulating the susceptibility of cells to death. Differential responses to optic nerve crush between two widely used strains of mice were used to define molecular networks associated with ganglion cell death and reactive gliosis. These results form the basis for our continuing interest in the modifiers of retinal injury. 18 Samples: 9 per strain (C57BL/6J & DBA/2J); 3 conditions per strain
Project description:Retinal ganglion cell (RGC) death is the final consequence of many blinding diseases, where there is considerable variation in the time course and severity of RGC loss. Indeed, this process appears to be influenced by a wide variety of genetic and environmental factors. In this study we explored the genetic basis for differences in ganglion cell death in two inbred strains of mice. We found that RGCs are more susceptible to death following optic nerve crush in C57BL/6J mice (54% survival) than in DBA2/J mice (62% survival). Using the Illumina Mouse-6 microarray, we identified 1,580 genes with significant change in expression following optic nerve crush in these two strains of mice. Our analysis of the changes occurring after optic nerve crush demonstrated that the greatest amount of change (44% of the variance) was due to the injury itself. This included changes associated with ganglion cell death, reactive gliosis, and abortive regeneration. The second pattern of gene changes (23% of the variance) was primarily related to differences in gene expressions observed between the C57BL/6J and DBA/2J mouse strains. The remaining changes in gene expression represent interactions between the effects of optic nerve crush and the genetic background of the mouse. We extracted one genetic network from this dataset that appears to be related to tissue remodeling. One of the most intriguing sets of changes included members of the crystallin family of genes, which may represent a signature of pathways modulating the susceptibility of cells to death. Differential responses to optic nerve crush between two widely used strains of mice were used to define molecular networks associated with ganglion cell death and reactive gliosis. These results form the basis for our continuing interest in the modifiers of retinal injury.
Project description:We used two groups of C57BL/6J mice, one with optic nerve crush on one eye, and another with no crush as control. Three mice were subjected to optic nerve crush, with sample names 121, 113, 114 and two were used as control with sample names 118 and 119. For the optic nerve crush, a surgical peritomy was made behind and above the eyeball and the eye muscles were gently retracted to expose the optic nerve. Dumont #5 forceps (FST) were used to crush the optic nerve approximately 0.5-1 mm behind the globe without damaging retinal vessels or affecting the blood supply.
Project description:Reactive gliosis is a complex process that involves profound changes in gene expression. We used microarray to indentify differentially expressed genes and to investigate the molecular mechanisms of reactive gliosis in optic nerve head in response to optic nerve crush injury. C57Bl/6 female mice were 6-8 weeks old at the time of optic nerve crush surgery. The optic nerve in the left eye was crush 1 mm behind the globe for 10 seconds and the right eye served as contralateral control. The animals were allowed to recover for 1 day, 3 day, 1 week, 3 weeks and 3 months before the optic nerve heads were collected. The naive control mice did not receive any surgery in either eye. Due to the small tissue size of the mouse optic nerve head, two optic nerve heads were pooled together for each microarray chip. The left eyes and the right eyes of two mice were combined respectively to form one pair of experiment and control samples. There were five biological replicates (10 mice) for each condition.
Project description:Mlycd encodes malonyl-CoA decarboxylase (MCD), which is an enzyme that localizes in the cytosolic, mitochondrial, and peroxisomal compartments and catalyzes the conversion of malonyl-CoA into acetyl-CoA. Malonyl-CoA can be converted into malonylcarnitine (C3DC). Patients with an autosomal recessive defect of MCD and MCD KO mice have pronounced elevations of C3DC. Analysis of plasma C3DC levels in the BxD genetic reference population revealed increased levels in BxD strains that harbor the DBA/2J haplotype at the site of the Mlycd gene. RNA sequencing was performed on two samples of DBA/2J mouse livers and two C57BL/6J mouse livers. Decreased expression of Mlycd gene as well as intronic reads in intron 2 were observed in DBA/2J livers. Long-read sequecing of DBA/2J livers in the Mlycd region confirmed an intracisternal A-particle (IAP) retrotransposon in intron 2 of the DBA/2J Mlycd sequence. To confirm the causal nature of the variant, DBA/2J mice with and without the C57BL/6J variant of Mlycd spliced in were tested for products of MCD enzymatic activity, and the C57BL/6J variant was able to rescue the phenotype seen in the DBA/2J mice.
Project description:Regulation of the immune response to Salmonella enterica serovar Typhimurium (S. Typhimurium) infection is a complex process, influenced by the interaction between genetic and environmental factors. Different inbred strains of mice exhibit distinct levels of resistance to S. Typhimurium infection, ranging from susceptible (e.g., C57BL/6J) to resistant (e.g., DBA/2J) strains. However, the underlying molecular mechanisms contributing to the host response remain elusive. In this study, we present a comprehensive proteomics profiling of spleen tissues from C57BL/6J and DBA/2J strains with different doses of S. Typhimurium infection by tandem tag mass coupled with two-dimensional liquid chromatography-tandem mass spectrometry (TMT-LC/LC-MS/MS). We identified and quantified 3,986 proteins, resulting in 475 differentially expressed proteins (DEPs) between C57BL/6J and DBA/2J strains. Functional enrichment analysis unveiled that the mechanism of innate immune responses to S. Typhimurium infection could be associated with several signaling pathways, including the interferon signaling pathway. We experimentally validated the roles of interferon signaling pathway in innate immune response to S. Typhimurium infection using IFN-γ neutralization assay. We further illustrated the roles of macrophage cells and pro-inflammatory cytokines in the mechanisms underlying the resistance to S. Typhimurium using qRT-PCR. Taken together, our results provide new insights into the genetic regulation of the immune response to S. Typhimurium infection in mice and might provide potential protein targets for controlling the infection.
Project description:Glaucoma is a common ocular disorder that is a leading cause of blindness worldwide. It is characterized by the dysfunction and loss of retinal ganglion cells (RGCs). Although many studies have implicated various molecules in glaucoma, no mechanism has been shown to be responsible for the earliest detectable damage to RGCs and their axons in the optic nerve. Here, we show that the leukocyte transendothelial migration pathway is activated in the optic nerve head at the earliest stages of disease in an inherited mouse model of glaucoma. This resulted in proinflammatory monocytes entering the optic nerve prior to detectable neuronal damage. A 1-time x-ray treatment prevented monocyte entry and subsequent glaucomatous damage. A single x-ray treatment of an individual eye in young mice provided that eye with long-term protection from glaucoma but had no effect on the contralateral eye. Localized radiation treatment prevented detectable neuronal damage and dysfunction in treated eyes, despite the continued presence of other glaucomatous stresses and signaling pathways. Injection of endothelin-2, a damaging mediator produced by the monocytes, into irradiated eyes, combined with the other glaucomatous stresses, restored neural damage with a topography characteristic of glaucoma. Together, these data support a model of glaucomatous damage involving monocyte entry into the optic nerve. Genome-wide assessment of gene expression changes was performed in DBA/2J-Gpnmb+, DBA/2J mice and irradiated DBA/2J mice at 8.5 and 10.5 months of age.
Project description:Susceptible and Resistant mouse strain, e.g. DBA/2J and C57BL/6J respectively, were inoculated with a highly pathogenic H5N1 influenza A virus (A/Hong Kong/213/2003) for 72 hours. Differences in expression were analyzed and use to identify candidate genes and pathways that contributed to the difference in H5N1 pathogenesis in these two strains. Recombinant inbred BXD strains are derived from the DBA/2J and C57BL/6 parent and were used to identify genetic loci associated with resistant to H5N1 infection.
Project description:This dataset is populated with transcriptome data across embryonic and postnatal development from two standard mouse strains, C57BL/6J and DBA/2J. Users can evaluate expression profiles across cerebellar development in a deep time series.
Project description:We used microarrays to analyse expression profiles of zebrafish retina after optic nerve crush to identify potential regulatory mechanisms that underpin central nerve regeneration Total RNA extracted from 4 samples (pooling 4 animals) of Zebrafish retinae after performing optic nerve crush (at day 3 post crush) vs 4 samples (pooling 4 animals) of control (unoperated) Zebrafish retinae