Helicase-like transcription factor (Hltf)-deletion activates Hmgb1-Rage axis and granzyme A-mediated killing of pancreatic β cells resulting in neonatal lethality
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA564434 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR10083376_1.fastq.gz | Fastqsanger.gz | |||
| SRR10083376_2.fastq.gz | Fastqsanger.gz | |||
| SRR10083377_1.fastq.gz | Fastqsanger.gz | |||
| SRR10083377_2.fastq.gz | Fastqsanger.gz | |||
| SRR10083378_1.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 28 |
Similar Datasets
Project description:Epigenetic mechanisms are integral to pancreatic β cell function. Promoter hypermethylation of the helicase like-transcription factor (HLTF) gene—a component of the cellular DNA damage response that contributes to genome stability—has been implicated in age-associated changes in β cells. To study HLTF, we generated global and β cell-specific (β) Hltf knockout (KO) immune competent (IC) and immune deficient (ID) Rag2-/IL2- mice. IC global and β Hltf KO mice were neonatal lethal whereas ID global and β Hltf KO newborn mice had normal survival. This focused our investigation on the effects of Rag2 interruption with common gamma chain interruption on β cell function/survival. Three-way transcriptomic (RNAseq) analyses of whole pancreata from IC and ID newborn β Hltf KO and wild type (Hltf +/+) controls combined with spatially resolved transcriptomic analysis of formalin fixed paraffin embedded tissue, immunohistochemistry and laser scanning confocal microscopy showed DNA damage caused by β Hltf KO in IC mice upregulated the Hmgb1-Rage axis and a gene signature for innate immune cells. Perforin-delivered granzyme A (GzmA) activation of DNase, Nme1, showed damaged nuclear single-stranded DNA (γH2AX immunostaining). This caspase-independent method of cell death was supported by transcriptional downregulation of Serpinc1 gene that encodes a serine protease inhibitor of GzmA. Increased transcriptional availability of complement receptors C3ar1 and C5ar1 likely invited crosstalk with Hmgb1 to amplify inflammation. This study explores the complex dialog between β cells and immune cells during development. It has implications for the initiation of type I diabetes in utero when altered gene expression that compromises genome stability invokes a localized inflammatory response.
2023-05-01 | GSE137060 | GEO
Project description:Epigenetic mechanisms are integral to pancreatic β cell function. Promoter hypermethylation of the helicase like-transcription factor (HLTF) gene-a component of the cellular DNA damage response that contributes to genome stability-has been implicated in age-associated changes in β cells. To study HLTF, we generated global and β cell-specific (β) Hltf knockout (KO) immune competent (IC) and immune deficient (ID) Rag2-/IL2- mice. IC global and β Hltf KO mice were neonatal lethal whereas ID global and β Hltf KO newborn mice had normal survival. This focused our investigation on the effects of Rag2 interruption with common gamma chain interruption on β cell function/survival. Three-way transcriptomic (RNAseq) analyses of whole pancreata from IC and ID newborn β Hltf KO and wild type (Hltf +/+) controls combined with spatially resolved transcriptomic analysis of formalin fixed paraffin embedded tissue, immunohistochemistry and laser scanning confocal microscopy showed DNA damage caused by β Hltf KO in IC mice upregulated the Hmgb1-Rage axis and a gene signature for innate immune cells. Perforin-delivered granzyme A (GzmA) activation of DNase, Nme1, showed damaged nuclear single-stranded DNA (γH2AX immunostaining). This caspase-independent method of cell death was supported by transcriptional downregulation of Serpinc1 gene that encodes a serine protease inhibitor of GzmA. Increased transcriptional availability of complement receptors C3ar1 and C5ar1 likely invited crosstalk with Hmgb1 to amplify inflammation. This study explores the complex dialog between β cells and immune cells during development. It has implications for the initiation of type I diabetes in utero when altered gene expression that compromises genome stability invokes a localized inflammatory response.
| S-EPMC10456192 | biostudies-literature
Project description:Cognitive impairment is a frequent manifestation of neuropsychiatric systemic lupus erythematosus (NPSLE), present in up to 80% of patients and leading to a diminished quality of life. We have developed a model of lupus-like cognitive impairment which is initiated when anti-DNA, anti-N-methyl D-aspartate receptor (NMDAR) cross- reactive antibodies, which are present in 30% of SLE patients, penetrate the hippocampus. This leads to immediate, self-limited excitotoxic death of CA1 pyramidal neurons followed by loss of dendritic arborization in the remaining CA1 pyramidal neurons and impaired spatial memory. Both microglia and C1q are required for dendritic loss. Here we show that this pattern of hippocampal injury creates a maladaptive homeostasis that is sustained for at least one year. It requires HMGB1 secretion by neurons to bind RAGE, a receptor for HMGB1 expressed on microglia, and leads to decreased expression of microglial LAIR-1, an inhibitory receptor for C1q. The angiotensin converting enzyme (ACE) inhibitor captopril, which can restore a healthy homeostasis, microglial quiescence, and intact spatial memory, leads to upregulation of LAIR-1. This paradigm highlights HMGB1:RAGE and C1q:LAIR-1 interactions as pivotal pathways in the microglial–neuronal interplay that defines a physiologic versus a maladaptive homeostasis.
2023-05-01 | GSE230077 | GEO
Project description:Background: We previously identified that high-mobility group box-1 (HMGB1) is increased and undergoes post-translational modifications (PTMs) in response to alcohol consumption. Here we hypothesized that specific PTMs, occurring mostly in hepatocytes and myeloid cells, could contribute to the pathogenesis of alcohol-associated liver disease (AALD). Methods: We used the Lieber-DeCarli (LDC) model of early alcohol-induced liver injury, combined with engineered viral vectors and genetic approaches to regulate the expression of HMGB1, its PTMs (reduced [H], oxidized [O], acetylated [Ac], both [O+Ac]), and its receptors (RAGE, TLR4) in a cell-specific manner (hepatocytes and/or myeloid cells). Results: Hmgb1 ablation in hepatocytes or myeloid cells partially protected, while ablation in both prevented steatosis, inflammation, IL1B production, and alcohol-induced liver injury. Hepatocytes were a major source of [H], [O], and [Ac] HMGB1, whereas myeloid cells produced only [H] and [Ac] HMGB1. Neutralization of HMGB1 prevented, whereas injection of [H] HMGB1 increased AALD, which was worsened by injection of [O] HMGB1. While [O] HMGB1 induced liver injury, [Ac] HMGB1 protected and counteracted the effects of [O] HMGB1 in AALD. [O] HMGB1 stimulated macrophage (MF) migration, activation, IL1B production and secretion. Ethanol-fed RageΔMye but not Tlr4ΔMye, RageΔHep, or Tlr4ΔHep mice were protected from AALD, indicating a crucial role of RAGE in myeloid cells for AALD. [O] HMGB1 recruited and activated myeloid cells through RAGE and contributed to steatosis, inflammation, and IL1B production in AALD. Conclusion: These results provide evidence for targeting [O] HMGB1 of hepatocyte origin as a ligand for RAGE signaling in myeloid cells and a driver of steatosis, inflammatory cell infiltration, and IL1B production in AALD. Importantly, we reveal that [Ac] HMGB1 offsets the noxious effects of [O] HMGB1 in AALD.
2024-09-28 | GSE278350 | GEO
Project description:Cell surface heparan sulfate (HS) plays an essential role in RAGE signaling by inducing RAGE oligomerization. To understand the physiological significance of HS-induced RAGE oligomerization in vivo, we generated RAGE knock-in mice (RageAHA/AHA) by introducing point mutations to specifically disrupt HS–RAGE interaction. The RAGE variant expressed by RageAHA/AHA mice demonstrated normal ligand-binding but greatly impaired capacity of HS-binding and oligomerization. To grasp the full scale of the alteration in gene expression caused by knocking out Rage, we performed a RNAseq analysis of mature neutrophils and lung from WT, RageAHA/AHA and Rage-/- mice. The overall number of differently regulated genes (DEGs) in Rage-/- neutrophils were almost 2.5 times higher than in RageAHA/AHA neutrophils (603 vs. 247). In contrast, the number of DEGs were much less in lungs compared to neutrophils in both strains (202 DEGs in Rage-/- lungs and merely 31 DEGs in RageAHA/AHA lungs), however the difference between the two genotypes was even more dramatic in lungs (7-fold) than we observed in neutrophils (2.5-fold). By comparing transcriptomes of neutrophils and lung tissues from RageAHA/AHA and Rage-/- mice, we present clear evidence that complete deficiency of RAGE had much broader impact on global gene expression compared to point mutations of RAGE.
2021-05-11 | GSE174178 | GEO
Project description:G-quadruplexes (G4s) form throughout the genome and influence important cellular processes, but their deregulation can challenge DNA replication fork progression and threaten genome stability. Here, we demonstrate an unexpected, dual role for the dsDNA translocase HLTF in G4 metabolism. First, we find that HLTF is enriched at G4s in the human genome and suppresses G4 accumulation throughout the cell cycle using its ATPase activity. This function of HLTF affects telomere maintenance by restricting alternative lengthening of telomeres, a process stimulated by G4s. We also show that HLTF and MSH2, a mismatch repair factor that binds G4s, act in independent pathways to suppress G4s and to promote resistance to G4 stabilization. In a second, distinct role, HLTF restrains DNA synthesis upon G4 stabilization by suppressing PrimPol-dependent repriming. Together, the dual functions of HLTF in the G4 response prevent DNA damage and potentially mutagenic replication to safeguard genome stability.
2024-08-13 | GSE247967 | GEO
Project description:The multi-ligand Receptor for AGE (RAGE) contributes to atherosclerosis in apolipoprotein (ApoE) null mice in both the non-diabetic and diabetic states. Previous studies using soluble RAGE, the extracellular ligand-binding domain of RAGE, or homozygous RAGE null mice showed that blockade or deletion of RAGE resulted in marked reduction in atherosclerotic lesion area and complexity compared to control animals. In parallel, significant down-regulation of inflammatory mediators and matrix metalloproteinases was evident in ApoE null mice aortas devoid of RAGE compared to those of ApoE null RAGE-expressing mice. Although these findings suggested that RAGE triggered pro-atherogenic mechanisms via regulation of inflammatory gene expression, these studies did not reveal the broader pathways by which RAGE contributed to atherosclerosis in ApoE null mice. Therefore, we performed Affymetrix gene expression arrays on aortas of non-diabetic and diabetic ApoE null mice expressing RAGE or devoid of RAGE at nine weeks of age, as this reflected a time point at which frank atherosclerotic lesions were not yet present, but, that we would be able to identify the genes likely involved in diabetes- and RAGE-dependent atherogenesis. The comparisons were as follows: 1. diabetic ApoE null relative to non-diabetic ApoE null; 2. non-diabetic ApoE null / RAGE null relative to non-diabetic ApoE null; 3. diabetic ApoE null / RAGE null relative to non-diabetic ApoE null / RAGE null; and 4. diabetic ApoE null / RAGE null relative to diabetic ApoE null aorta. Our data reveal that there is very little overlap of the genes which are differentially expressed both in the onset of diabetes in ApoE null mice, and in the effect of RAGE deletion in diabetic ApoE null mice. We next performed a Pathway-Express analysis to determine the pathways that were most associated with the onset of diabetes in ApoE null mice and the effect of RAGE gene deletion in diabetic ApoE null mice. Rigorous statistical analysis was undertaken and revealed that the transforming growth factor-beta pathway (tgf-beta) and focal adhesion pathways might be expected to play a significant role in both the mechanism by which diabetes facilitates the formation of atherosclerotic plaques in ApoE null mice, and the mechanism by which deletion of RAGE ameliorates this effect. We focused on three genes of the tgf-betafamily which were found to be up-regulated in diabetic vs. non-diabetic ApoE null aorta, and which were reduced by deletion of RAGE. These included: thrombospondin1 (Thbs1), transforming growth factor-beta (tgf-beta) and rho-associated kinase (ROCK1). Real-time quantitative polymerase chain reaction and Western blotting experiments were performed, as well as ROCK1 activity assays in mouse aorta, and validated the findings of the Affymetrix gene array. Further, confocal microscopy revealed that a principal cell type in the ApoE null aorta expressing these factors was the vascular smooth muscle cell. Our data suggest the novel finding that the observed reduction of accelerated atherosclerosis in diabetic ApoE null / RAGE null vs. diabetic ApoE null mice occurs, all or in part, through the ROCK1 branch of the TGF-betapathway. We have inferred a detailed mechanism for this process. Taken together, these data suggest that suppression of ROCK1 activity in the atherosclerosis-vulnerable vessel wall, especially in diabetes, but in non-diabetes as well, may underlie the beneficial effects of RAGE antagonism and genetic deletion in murine models. These findings highlight logical and novel targets for therapeutic intervention in cardiovascular disease and diabetes. 1. diabetic ApoE null relative to non-diabetic ApoE null; 2. non-diabetic ApoE null / RAGE null relative to non-diabetic ApoE null; 3. diabetic ApoE null / RAGE null relative to non-diabetic ApoE null / RAGE null; and 4. diabetic ApoE null / RAGE null relative to diabetic ApoE null aorta. There were 4 mice in each group initially. However there are only 3 non-diabetic ApoE null / RAGE null mice in the final experimental sample in group 3 due to a failure to generate cRNA from that sample. All samples were normalized to remove chip-dependent regularities using the RMA method. Chips and controls at each combination of genotype and disease sate were normalized together. The statistical significance of differential expression was calculated using the empirical Bayesian LIMMA (LInear Model for MicroArrays) method A cut-off B>0 was used for the statistical significance of gene expression.
2010-03-07 | E-GEOD-15729 | biostudies-arrayexpress
Project description:Lupus autoantibodies initiate a maladaptive homeostasis sustained by HMGB1:RAGE signaling and reversed by LAIR-1:C1q signaling
| PRJNA957326 | ENA
Project description:Testing the consequences of the absence of the chromatin-associated HMGB1 protein on the transcriptome in Arabidopsis. Keywords: Comparison of mutant and wildtype samples. Four replicate RNA extractions were performed of each genotype using independent pools of plants. hmgb1#1 (Cy5) vs. Col-0#1 (Cy3) Col-0#2 (Cy5) vs. hmgb1#2 (Cy3) dye-swap hmgb1#3 (Cy5) vs. Col-0#3 (Cy3) Col-0#5 (Cy5) vs. hmgb1#4 (Cy3) dye-swap Samples were hybridized in two dye-swaps. The data were normalized over all 4 hybridizations to obtain one, single log-ratio(Sample/Reference). The raw data files of all four of the hybridizations are attached to the Sample.
2008-11-23 | E-GEOD-10638 | biostudies-arrayexpress
Project description:High Mobility Group Box 1 (HMGB1) is a highly abundant and evolutionarily conserved non-histone chromatin component with the ability to bind and bend DNA. The protein is involved in fundamental nuclear processes including nucleosome sliding, transcription, replication, V(D)J recombination and DNA transposition. To assess the functional impact of HMGB1 on transcription we performed gene expression profile analyses of mouse embryonic fibroblasts, wild-type or knockout for the Hmgb1 gene 2 genetic backgrounds: wild-type (Wt), Hmgb1-/- (KO), 3 biological replicates (rep1, rep2, rep3; S phase synchronized cells in duplicate only), no technical replicates. Each pair of wt and Hmgb1-/- MEFs was isolated from embryos born from a single Hmgb1+/- mother crossed with a Hmgb1 +/- male. Total RNAs from three pairs of MEFs, derived from three different mothers and cultured up to passage 3, were extracted using mirVana miRNA Isolation Kit (Ambion) and analyzed on the Illumina BeadsArray platform.
2013-10-01 | E-GEOD-18463 | biostudies-arrayexpress