JPH2 Junctophilin-2: Membrane-binding protein that provides a structural bridge between the plasma membrane and the sarcoplasmic reticulum and is required for normal excitation-contraction coupling in cardiomyocytes. Provides a structural foundation for functional cross-talk between the cell surface and intracellular Ca(2+) release channels by maintaining the 12-15 nm gap between the sarcolemma and the sarcoplasmic reticulum membranes in the cardiac dyads. Necessary for proper intracellular Ca(2+) signaling in cardiac myocytes via its involvement in ryanodine receptor-mediated calcium ion release. Contributes to the construction of skeletal muscle triad junctions. Junctophilin-2 N-terminal fragment: Transcription repressor required to safeguard against the deleterious effects of cardiac stress. Generated following cleavage of the Junctophilin-2 chain by calpain in response to cardiac stress in cardiomyocytes. Following cleavage and release from the membrane, translocates to the nucleus, binds DNA and represses expression of genes implicated in cell growth and differentiation, hypertrophy, inflammation and fibrosis. Modifies the transcription profile and thereby attenuates pathological remodeling in response to cardiac stress. Probably acts by competing with MEF2 transcription factors and TATA-binding proteins. Belongs to the junctophilin family. Specifically expressed in skeletal muscle and heart. 2 alternatively spliced human isoforms have been reported. Note: This description may include information from UniProtKB.
Protein type: Contractile; Endoplasmic reticulum; Membrane protein, integral
Chromosomal Location of mouse Ortholog: 2|2 H2-H3
Cellular Component:  endoplasmic reticulum; endoplasmic reticulum membrane; junctional membrane complex; membrane; nucleus; plasma membrane; sarcoplasmic reticulum; Z disc
Molecular Function:  core promoter sequence-specific DNA binding; DNA binding; DNA-binding transcription repressor activity, RNA polymerase II-specific; phosphatidic acid binding; phosphatidylinositol-3,4,5-trisphosphate binding; phosphatidylinositol-3,5-bisphosphate binding; phosphatidylinositol-3-phosphate binding; phosphatidylinositol-4,5-bisphosphate binding; phosphatidylinositol-4-phosphate binding; phosphatidylinositol-5-phosphate binding; phosphatidylserine binding; protein binding
Biological Process:  calcium ion homeostasis; multicellular organism development; negative regulation of DNA-templated transcription; negative regulation of transcription by RNA polymerase II; positive regulation of cytosolic calcium ion concentration; positive regulation of ryanodine-sensitive calcium-release channel activity; regulation of cardiac muscle tissue development
Reference #:  Q9ET78 (UniProtKB)
Alt. Names/Synonyms: 1110002E14Rik; JP-; JP-2; Jp2; JP2NT; Jph2; junctophilin 2; Junctophilin type 2; Junctophilin-2; Junctophilin-2 N-terminal fragment; OTTMUSP00000001086
Gene Symbols: Jph2
Molecular weight: 74,692 Da
Basal Isoelectric point: 8.16  Predict pI for various phosphorylation states
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Protein Structure Not Found.

Cross-references to other databases:  AlphaFold  |  STRING  |  BioGPS  |  Pfam  |  Phospho.ELM  |  NetworKIN  |  UniProtKB  |  Entrez-Gene  |  GenPept  |  Ensembl Gene  |  Ensembl Protein