Junctophilin-2 Rabbit Polyclonal Antibody (0407-9)

UNIPROT #

Q9BR39

PROTEIN NAME

Junctophilin-2

SYNONYMS

FLJ40969 antibody;JP-2 antibody;JP2 antibody;Jph2 antibody;JPH2_HUMAN antibody;Junctophilin 2 antibody;Junctophilin type 2 antibody;Junctophilin-2 antibody;OTTHUMP00000031651 antibody;OTTHUMP00000031652 antibody

SEQUENCE SIMILARITIES

Belongs to the junctophilin family.

TISSUE SPECIFICITY

Specifically expressed in skeletal muscle and heart.

POST-TRANSLATIONAL MODIFICATION

Phosphorylation on Ser-165, probably by PKC, affects RYR1-mediated calcium ion release, interaction with TRPC3, and skeletal muscle myotubule development.; Proteolytically cleaved by calpain in response to cardiac stress. The major cleavage site takes place at the C-terminus and leads to the release of the Junctophilin-2 N-terminal fragment chain (JP2NT).

SUBCELLULAR LOCATION

Cell membrane, Sarcoplasmic reticulum membrane, Endoplasmic reticulum membrane; Nucleus.

FUNCTION

Junctophilin 2, also known as JPH2, is a protein which in humans is encoded by the JPH2 gene. Alternative splicing has been observed at this locus and two variants encoding distinct isoforms are described. Junctional complexes between the plasma membrane and endoplasmic/sarcoplasmic reticulum are a common feature of all excitable cell types and mediate cross talk between cell surface and intracellular ion channels. The protein encoded by this gene 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 membrane occupation and recognition nexus (MORN) domain that shows specific affinity for the plasma membrane. JPH2 is a member of the junctophilin gene family (the other members of the family are JPH1, JPH3, and JPH4) and is the predominant isoform in cardiac tissue, but is also expressed with JPH1 in skeletal muscle. The JPH2 protein product plays a critical role in maintaining the spacing a geometry of the cardiac dyad - the space between the plasma membrane and sarcoplasmic reticulum. These cardiac dyads also known as junctional membrane complexes or calcium release units are thought to play a key role in calcium induced calcium release by approximating L-type calcium channels on the plasma membrane and ryanodine receptor type 2 on the sarcoplasmic reticulum. JPH2 also contains an evolutionarily conserved nuclear localization signal and a DNA binding domain. During (heart) disease, stress-activated calpain converts the full length JPH2 into fragments. The N-terminal fragment (including nuclear localization signal and DNA binding domain) is translocated to nucleus and regulates gene transcription.