JPH1

JPH1 (Junctophilin 1) encodes the protein which is a component of junctional complexes and is composed of a C-terminal hydrophobic segment spanning the endoplasmic/sarcoplasmic reticulum membrane and a remaining cytoplasmic domain that shows specific affinity for the plasma membrane. An important paralog of this gene is JPH3.

Full Name

junctophilin 1

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. JPH1 contributes to the construction of the skeletal muscle triad by linking the t-tubule (transverse-tubule) and SR (sarcoplasmic reticulum) membranes.

Biological Process

Calcium ion transport into cytosolManual Assertion Based On ExperimentTAS:BHF-UCL
Muscle organ developmentIEA:Ensembl
Regulation of ryanodine-sensitive calcium-release channel activityManual Assertion Based On ExperimentTAS:BHF-UCL

Cellular Location

Cell membrane; Endoplasmic reticulum membrane; Sarcoplasmic reticulum membrane. 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 skeletal muscle cells, it is predominantly localized at the junction of the A and I bands (By similarity).

Topology

Cytoplasmic: 1-639
Helical: 640-660