PTPRN2

The protein encoded by this gene is a member of the protein tyrosine phosphatase (PTP) family. PTPs are known to be signaling molecules that regulate a variety of cellular processes including cell growth, differentiation, mitotic cycle, and oncogenic transformation. This PTP possesses an extracellular region, a single transmembrane region, and a single intracellular catalytic domain, and thus represents a receptor-type PTP. The catalytic domain of this PTP is most closely related to PTPRN/IA-2beta. This PTP and PTPRN are both found to be major autoantigens associated with insulin-dependent diabetes mellitus. Three alternatively spliced transcript variants of this gene, which encode distinct proteins, have been reported. [provided by RefSeq]

Full Name

protein tyrosine phosphatase, receptor type, N polypeptide 2

Function

Plays a role in vesicle-mediated secretory processes. Required for normal accumulation of secretory vesicles in hippocampus, pituitary and pancreatic islets. Required for the accumulation of normal levels of insulin-containing vesicles and preventing their degradation. Plays a role in insulin secretion in response to glucose stimuli. Required for normal accumulation of the neurotransmitters norepinephrine, dopamine and serotonin in the brain. In females, but not in males, required for normal accumulation and secretion of pituitary hormones, such as luteinizing hormone (LH) and follicle-stimulating hormone (FSH) (By similarity).
Required to maintain normal levels of renin expression and renin release (By similarity).
May regulate catalytic active protein-tyrosine phosphatases such as PTPRA through dimerization (By similarity).
Has phosphatidylinositol phosphatase activity; the PIPase activity is involved in its ability to regulate insulin secretion. Can dephosphorylate phosphatidylinositol 4,5-biphosphate (PI(4,5)P2), phosphatidylinositol 5-phosphate and phosphatidylinositol 3-phosphate (By similarity).
Regulates PI(4,5)P2 level in the plasma membrane and localization of cofilin at the plasma membrane and thus is indirectly involved in regulation of actin dynamics related to cell migration and metastasis; upon hydrolyzation of PI(4,5)P2 cofilin is released from the plasma membrane and acts in the cytoplasm in severing F-actin filaments (PubMed:26620550).

Biological Process

Insulin secretion involved in cellular response to glucose stimulusISS:UniProtKB
Lipid metabolic processIEA:UniProtKB-KW
Neurotransmitter secretionISS:UniProtKB
Protein dephosphorylationManual Assertion Based On ExperimentTAS:ProtInc
Regulation of secretionManual Assertion Based On ExperimentIBA:GO_Central

Involvement in disease

Autoantigen in insulin-dependent diabetes mellitus (IDDM).

Topology

Extracellular: 22-615
Helical: 616-636
Cytoplasmic: 637-1015

PTM

Subject to proteolytic cleavage at multiple sites.