Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Junctophilin-2 Regulates Store-Operated Calcium Entry to Drive Cardiac Fibroblast Activation, Fibrotic Repair, and Angiogenesis After Myocardial Infarction

ABSTRACT: Calcium homeostasis in cardiac fibroblasts (CFs) are thought to play a critical role in myocardial repair and remodeling following injury. Junctophilin-2 (JP2) is a structural protein known to regulate intracellular calcium signaling and excitation-contraction coupling in cardiomyocytes. However, the role of JP2 in CF biology remains unexplored. To investigate the functional role of JP2 in CFs, we transduced primary CFs with adenoviruses expressing GFP, JP2, or a JP2 targetting shRNA and determined differentially expressed genes via RNA-sequencing. JP2 overepression and silencing had opposite effects on the expression of genes associated with fibrosis, migration, and cell division.

ORGANISM(S): Mus musculus

PROVIDER: GSE287096 | GEO | 2025/06/23

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

Preventing Site-specific Calpain Proteolysis of Junctophilin-2 Protects Against Stress-induced E-C Uncoupling and Heart Failure

Project description:Junctophilin-2 (JP2) is an essential component of the excitation-contraction coupling apparatus in cardiomyocytes and becomes proteolytically cleaved in response to stress. We previously mapped the primary calpain cleavage site to JP2 residues 565-566 using in vitro assays. To determine whether this site is responsible for JP2 cleavage in vivo, we generated calpain resistant JP2 (JP2CR) knock-in mice lacking this site. We find JP2 is not cleaved in JP2CR mice during pressure overload stress resulting in better cardiac outcomes and an attenuated transcriptional response relative to wildtype mice.

2024-08-01 | GSE235601 | GEO

Calpain Cleavage of Junctophilin-2 generates a Spectrum of Calcium-dependent Cleavage Products and DNA-rich NT1-Fragment Domains in Cardiomyocytes

Project description:Calpains are calcium (Ca2+) activated neutral proteases that are involved in several essential signaling pathways. One Calpain-specific proteolytic target is Junctophilin-2 (JP2), an important structural protein of Ca2+ release units required for the excitation-contraction coupling in cardiomyocytes. While downregulation of JP2 by Calpain cleavage in mouse models of heart failure has been reported previously, the precise molecular identity of the Calpain cleavage sites and the (patho-) physiological roles of the JP2 proteolytic products remain controversial. We systematically analyzed the JP2 cleavage fragments as function of Calpain-1 versus Calpain-2 proteolytic activities, revealing that both Calpain isoforms preferentially cleave mouse JP2 at R565 but subsequently also at three additional secondary Calpain cleavage sites. We identified the Calpain-specific primary cleavage products not only in mouse but also in human iPSC-derived cardiomyocytes (hiPSC-CMs). Knockout of RyR2 in hiPSC-CMs destabilized JP2 resulting in an increase of the Calpain-specifc cleavage fragments. The primary N-terminal cleavage product (NT1) accumulated in the nucleus of mouse and human cardiomyocytes in a Ca2+ dependent manner, closely associated with DNA-rich chromosomal regions, where NT1 is proposed to function as a cardioprotective transcriptional regulator in heart failure. Taken together, our data suggest that stabilizing NT1 by preventing secondary cleavage events by Calpain and other proteases could be an important therapeutic target for future studies.

2022-08-12 | PXD031321 | Pride

Calpain Cleavage of Junctophilin-2 generates a Spectrum of Calcium-dependent Cleavage Products and DNA-rich NT1-Fragment Domains in Cardiomyocytes - PRM Dataset

Project description:Calpains are calcium (Ca2+) activated neutral proteases that are involved in several essential signaling pathways. One Calpain-specific proteolytic target is Junctophilin-2 (JP2), an important structural protein of Ca2+ release units required for the excitation-contraction coupling in cardiomyocytes. While downregulation of JP2 by Calpain cleavage in mouse models of heart failure has been reported previously, the precise molecular identity of the Calpain cleavage sites and the (patho-) physiological roles of the JP2 proteolytic products remain controversial. We systematically analyzed the JP2 cleavage fragments as function of Calpain-1 versus Calpain-2 proteolytic activities, revealing that both Calpain isoforms preferentially cleave mouse JP2 at R565, but subsequently also at three additional secondary Calpain cleavage sites. We identified the Calpain-specific primary cleavage products not only in mouse but also in human iPSC-derived cardiomyocytes (hiPSC-CMs). Knockout of RyR2 in hiPSC-CMs destabilized JP2 resulting in an increase of the Calpain-specifc cleavage fragments. The primary N-terminal cleavage product (NT1) accumulated in the nucleus of mouse and human cardiomyocytes in a Ca2+ dependent manner, closely associated with DNA-rich chromosomal regions, where NT1 is proposed to function as a cardioprotective transcriptional regulator in heart failure. Taken together, our data suggest that stabilizing NT1 by preventing secondary cleavage events by Calpain and other proteases could be an important therapeutic target for future studies.

2022-08-12 | PXD031424 | Pride

Transcriptome Profile of Cultured Adult Mouse Cardiomyocytes Overexpressing JP2 or JP2NT

Project description:Calpain mediated cleavage transforms the full-length junctophilin 2 (JP2) from a structural protein into a transcriptional regulator (JP2 N-terminal trancate - JP2NT). We used affymetrix Genechip to reveal the differentially expressed transcripts induced by overexpression of JP2NT and JP2 in adult cultured mouse cardiomyocytes.

2019-01-31 | GSE121545 | GEO

Junctophilin-2 Regulates Store-Operated Calcium Entry to Drive Cardiac Fibroblast Activation, Fibrotic Repair, and Angiogenesis After Myocardial Infarction

Project description:Junctophilin-2 Regulates Store-Operated Calcium Entry to Drive Cardiac Fibroblast Activation, Fibrotic Repair, and Angiogenesis After Myocardial Infarction

| PRJNA1211116 | ENA

Gene Therapy with the N-terminus of Junctophilin-2 Improves Hypertrophy and Heart Failure in Mice

Project description:Our previous work found a variety of cardiac stresses initiate site-specific cleavage of junctophilin-2 (JP2), an essential component of the E-C coupling apparatus, producing a 75-kDa N-terminal fragment (JP2NT) which unexpectedly translocates into cardiomyocyte nuclei and functions as a transcriptional repressor. We also determined that transgenic overexpression of JP2NT in cardiomyocytes attenuates pressure-overload induced hypertrophy and heart failure by blunting the induction of maladaptive transcripts. To test whether JP2NT could be utilized by gene therapy approaches for treating heart failure, we developed cardiotropic adeno-associated GFP and JP2NT expressing viruses for testing in a preclinical model of heart failure. Our results show that the transcriptional and pathological changes from pressure overload can be reduced through viral expression of JP2NT once hypertrophy and heart failure has already begun.

2022-09-06 | GSE189475 | GEO

Differential regulation of membrane potential during store-operated calcium entry in neutrophil subsets

Project description:Calcium signals are initiated in immune cells by the process of store-operated calcium entry (SOCE), where receptor activation triggers transient calcium release from the endoplasmic reticulum, followed by opening of plasma membrane calcium-release activated calcium (CRAC) channels. ORAI1, ORAI2 and ORAI3 are known to comprise the CRAC channel, however the contributions of individual isoforms to neutrophil function is not well understood. Here we show that loss of ORAI1 partially decreases calcium influx while loss of both ORAI1 and ORAI2 completely abolishes store-operated calcium entry. In other immune cell types, loss of ORAI2 enhances SOCE. In contrast, we find that ORAI2-deficient neutrophils display decreased calcium influx, which is correlated with measurable differences in regulation of neutrophil membrane potential via KCa3.1. Decreased SOCE in ORAI1-, ORAI2- and ORAI1/2-deficient neutrophils impairs multiple neutrophil functions including phagocytosis, degranulation, leukotriene and ROS production, rendering ORAI1/2-deficient mice highly susceptible to staphylococcal infection. This study demonstrates that ORAI1 and ORAI2 are the primary components of the neutrophil CRAC channel and identifies novel subpopulations of neutrophils where cell membrane potential functions as a rheostat to modulate the SOCE response. These findings have implications for new mechanisms that modulate neutrophil function during infection, acute and chronic inflammatory conditions, and cancer.

2020-09-01 | GSE157200 | GEO

Hypertrophy in skeletal myotubes induced by junctophilin-2 mutant, Y141H, involves an increase in store-operated Ca2+ entry via Orai1.

Project description:Junctophilins (JPs) play an important role in the formation of junctional membrane complexes (JMC) in striated muscle by physically linking the transverse-tubule and sarcoplasmic reticulum (SR) membranes. Researchers have found five JP2 mutants in humans with hypertrophic cardiomyopathy. Among these, Y141H and S165F are associated with severely altered Ca(2+) signaling in cardiomyocytes. We previously reported that S165F also induced both hypertrophy and altered intracellular Ca(2+) signaling in mouse skeletal myotubes. In the present study, we attempted to identify the dominant-negative role(s) of Y141H in primary mouse skeletal myotubes. Consistent with S165F, Y141H led to hypertrophy and altered Ca(2+) signaling (a decrease in the gain of excitation-contraction coupling and an increase in the resting level of myoplasmic Ca(2+)). However, unlike S165F, neither ryanodine receptor 1-mediated Ca(2+) release from the SR nor the phosphorylation of the mutated JP2 by protein kinase C was related to the altered Ca(2+) signaling by Y141H. Instead, abnormal JMC and increased SOCE via Orai1 were found, suggesting that the hypertrophy caused by Y141H progressed differently from S165F. Therefore JP2 can be linked to skeletal muscle hypertrophy via various Ca(2+) signaling pathways, and SOCE could be one of the causes of altered Ca(2+) signaling observed in muscle hypertrophy.

| S-EPMC3340289 | biostudies-literature

Store-Operated Calcium Channels.

Project description:Store-operated calcium channels (SOCs) are a major pathway for calcium signaling in virtually all metozoan cells and serve a wide variety of functions ranging from gene expression, motility, and secretion to tissue and organ development and the immune response. SOCs are activated by the depletion of Ca(2+) from the endoplasmic reticulum (ER), triggered physiologically through stimulation of a diverse set of surface receptors. Over 15 years after the first characterization of SOCs through electrophysiology, the identification of the STIM proteins as ER Ca(2+) sensors and the Orai proteins as store-operated channels has enabled rapid progress in understanding the unique mechanism of store-operate calcium entry (SOCE). Depletion of Ca(2+) from the ER causes STIM to accumulate at ER-plasma membrane (PM) junctions where it traps and activates Orai channels diffusing in the closely apposed PM. Mutagenesis studies combined with recent structural insights about STIM and Orai proteins are now beginning to reveal the molecular underpinnings of these choreographic events. This review describes the major experimental advances underlying our current understanding of how ER Ca(2+) depletion is coupled to the activation of SOCs. Particular emphasis is placed on the molecular mechanisms of STIM and Orai activation, Orai channel properties, modulation of STIM and Orai function, pharmacological inhibitors of SOCE, and the functions of STIM and Orai in physiology and disease.

| S-EPMC4600950 | biostudies-literature

Selective modulation of gene expression in activated normal human peripheral blood mononuclear cells by store-operated calcium entry blocker BTP2

Project description:Calcium is a critical signaling molecule in many cell types including immune cells. The calcium-release activated calcium channels (CRAC) responsible for store-operated calcium entry (SOCE) in immune cells are gated by STIM family members functioning as sensors of Ca2+ store content in the endoplasmic reticulum. We investigated the effect of SOCE blockers BTP2 and CM4620 on human peripheral blood mononuclear cells (PBMCs) polyclonally-stimulated with the mitogen phytohemagglutinin (PHA).

2025-04-28 | GSE295784 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data