JPH2 Antibody – Rabbit Polyclonal

Function: Junctophilins contribute to the formation of junctional membrane complexes (JMCs) which link the plasma membrane with the endoplasmic or sarcoplasmic reticulum in excitable cells. Provides a structural foundation for functional cross-talk between the cell surface and intracellular calcium release channels. JPH2 is necessary for proper intracellular Ca2+ signaling in cardiac myocytes via its involvement in ryanodine receptor-mediated calcium ion release. Contributes to the construction of skeletal muscle triad junctions. Ref.7

Subcellular location: Cell membrane; Peripheral membrane protein

By similarity. Endoplasmic reticulum membrane; Single-pass type IV membrane protein

By similarity. Sarcoplasmic reticulum membrane; Single-pass type IV membrane protein

By similarity. Note: Localized predominantly on the plasma membrane. The transmembrane domain is anchored in endoplasmic/sarcoplasmic reticulum membrane, while the N-terminal part associates with the plasma membrane. In heart cells, it predominantly associates along Z lines within myocytes. In skeletal muscle, it is specifically localized at the junction of A and I bands

By similarity.

Tissue specificity: Specifically expressed in skeletal muscle and heart. Ref.4

Domain: The MORN (membrane occupation and recognition nexus) repeats contribute to the plasma membrane binding, possibly by interacting with phospholipids

By similarity.

Post-translational modification: Phosphorylation on Ser-165, probably by PKC, affects RYR1-mediated calcium ion release, interaction with TRPC3, and skeletal muscle myotubule development.

Involvement in disease: Cardiomyopathy, familial hypertrophic 17 (CMH17) [MIM:613873]: A hereditary heart disorder characterized by ventricular hypertrophy, which is usually asymmetric and often involves the interventricular septum. The symptoms include dyspnea, syncope, collapse, palpitations, and chest pain. They can be readily provoked by exercise. The disorder has inter- and intrafamilial variability ranging from benign to malignant forms with high risk of cardiac failure and sudden cardiac death.Note: The disease is caused by mutations affecting the gene represented in this entry. Ref.9

Sequence similarities: Belongs to the junctophilin family.Contains 8 MORN repeats.