Harmonizome 3.0

spastic paraplegia 21 (autosomal recessive, Mast syndrome)

The protein encoded by this gene binds to the hydrophobic C-terminal amino acids of CD4 which are involved in repression of T cell activation. The interaction with CD4 is mediated by the noncatalytic alpha/beta hydrolase fold domain of this protein. It is thus proposed that this gene product modulates the stimulatory activity of CD4. Mutations in this gene are associated with autosomal recessive spastic paraplegia 21 (SPG21), also known as mast syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2014]

histamine N-methyltransferase

In mammals, histamine is metabolized by two major pathways: N(tau)-methylation via histamine N-methyltransferase and oxidative deamination via diamine oxidase. This gene encodes the first enzyme which is found in the cytosol and uses S-adenosyl-L-methionine as the methyl donor. In the mammalian brain, the neurotransmitter activity of histamine is controlled by N(tau)-methylation as diamine oxidase is not found in the central nervous system. A common genetic polymorphism affects the activity levels of this gene product in red blood cells. Multiple alternatively spliced transcript variants that encode different proteins have been found for this gene. [provided by RefSeq, Jul 2008]

carboxypeptidase A3 (mast cell)

This gene encodes a member of the carboxypeptidase A family of zinc metalloproteases. The encoded preproprotein is proteolytically processed to generate a mature protease that is released by mast cells and may be involved in the degradation of endogenous proteins and the inactivation of venom-associated peptides. Expression of this gene may be elevated in human asthma patients. [provided by RefSeq, Nov 2015]

mast cell immunoglobulin-like receptor 1

Predicted to enable transmembrane signaling receptor activity. Predicted to be involved in cell surface receptor signaling pathway; mast cell degranulation; and negative regulation of mast cell activation. Predicted to be located in plasma membrane. Predicted to be active in external side of plasma membrane. [provided by Alliance of Genome Resources, Mar 2025]

histamine receptor H4

Histamine is a ubiquitous messenger molecule released from mast cells, enterochromaffin-like cells, and neurons. Its various actions are mediated by a family of histamine receptors, which are a subset of the G-protein coupled receptor superfamily. This gene encodes a histamine receptor that is predominantly expressed in haematopoietic cells. The protein is thought to play a role in inflammation and allergy reponses. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2009]

histamine receptor H2

Histamine is a ubiquitous messenger molecule released from mast cells, enterochromaffin-like cells, and neurons. Its various actions are mediated by histamine receptors H1, H2, H3 and H4. Histamine receptor H2 belongs to the family 1 of G protein-coupled receptors. It is an integral membrane protein and stimulates gastric acid secretion. It also regulates gastrointestinal motility and intestinal secretion and is thought to be involved in regulating cell growth and differentiation. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Aug 2008]

histamine receptor H3

Histamine is a ubiquitous messenger molecule released from mast cells, enterochromaffin-like cells, and neurons. Its various actions are mediated by histamine receptors H1, H2, H3 and H4. This gene encodes one of the histamine receptors (H3) which belongs to the family 1 of G protein-coupled receptors. It is an integral membrane protein and can regulate neurotransmitter release. This receptor can also increase voltage-dependent calcium current in smooth muscles and innervates the blood vessels and the heart in cardiovascular system. [provided by RefSeq, Jul 2008]

histamine receptor H1

Histamine is a ubiquitous messenger molecule released from mast cells, enterochromaffin-like cells, and neurons. Its various actions are mediated by histamine receptors H1, H2, H3 and H4. The protein encoded by this gene is an integral membrane protein and belongs to the G protein-coupled receptor superfamily. It mediates the contraction of smooth muscles, the increase in capillary permeability due to contraction of terminal venules, the release of catecholamine from adrenal medulla, and neurotransmission in the central nervous system. It has been associated with multiple processes, including memory and learning, circadian rhythm, and thermoregulation. It is also known to contribute to the pathophysiology of allergic diseases such as atopic dermatitis, asthma, anaphylaxis and allergic rhinitis. Multiple alternatively spliced variants, encoding the same protein, have been identified. [provided by RefSeq, Jan 2015]

mast cell-expressed membrane protein 1

This gene encodes a single-pass transmembrane protein. Based on its expression pattern, it is speculated to be involved in regulating mast cell differentiation or immune responses. [provided by RefSeq, Jul 2008]

chymase 1, mast cell

This gene encodes a chymotryptic serine proteinase that belongs to the peptidase family S1. It is expressed in mast cells and is thought to function in the degradation of the extracellular matrix, the regulation of submucosal gland secretion, and the generation of vasoactive peptides. In the heart and blood vessels, this protein, rather than angiotensin converting enzyme, is largely responsible for converting angiotensin I to the vasoactive peptide angiotensin II. Alternative splicing results in multiple variants. [provided by RefSeq, Apr 2015]

Ca++-dependent secretion activator 2

This gene encodes a member of the calcium-dependent activator of secretion (CAPS) protein family, which are calcium binding proteins that regulate the exocytosis of synaptic and dense-core vesicles in neurons and neuroendocrine cells. Mutations in this gene may contribute to autism susceptibility. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Nov 2009]

secretion associated, Ras related GTPase 1A

Enables G protein activity and amino acid sensor activity. Involved in COPII-coated vesicle budding; cellular response to leucine starvation; and negative regulation of TORC1 signaling. Is active in COPII vesicle coat; endoplasmic reticulum exit site; and lysosomal membrane. [provided by Alliance of Genome Resources, Mar 2025]

secretion associated, Ras related GTPase 1B

The protein encoded by this gene is a small GTPase that acts as a homodimer. The encoded protein is activated by the guanine nucleotide exchange factor PREB and is involved in protein transport from the endoplasmic reticulum to the Golgi. This protein is part of the COPII coat complex. Defects in this gene are a cause of chylomicron retention disease (CMRD), also known as Anderson disease (ANDD). Two transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Mar 2010]

wntless Wnt ligand secretion mediator

Enables Wnt-protein binding activity and identical protein binding activity. Involved in positive regulation of cell communication and protein transport. Located in several cellular components, including Golgi apparatus; early endosome; and endoplasmic reticulum membrane. Implicated in Zaki syndrome. [provided by Alliance of Genome Resources, Mar 2025]

Ca++-dependent secretion activator

This gene encodes a novel neural/endocrine-specific cytosolic and peripheral membrane protein required for the Ca2+-regulated exocytosis of secretory vesicles. The protein acts at a stage in exocytosis that follows ATP-dependent priming, which involves the essential synthesis of phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2). Alternative splicing has been observed at this locus and three variants, encoding distinct isoforms, are described. [provided by RefSeq, Aug 2008]

secretion regulating guanine nucleotide exchange factor

Predicted to enable guanyl-nucleotide exchange factor activity. Involved in negative regulation of protein secretion. Located in cytosol and nucleoplasm. Biomarker of atherosclerosis. [provided by Alliance of Genome Resources, Mar 2025]