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Prolactin is a pituitary hormone that plays a role in the stimulation of milk production, salt and water regulation, growth, development and reproduction. The primary step in its action is the binding to a specific membrane receptor (prolactin receptor) which belongs to the superfamily of class 1 cytokine receptors. Prolactin is a hormone involved in a range of significant functions including ion transport and osmoregulation, stimulation of milk, protein synthesis as well as the regulation of numerous reproductive functions. Prolactin exerts its influence on different cell types through a signal transduction pathway which begins with the binding of the hormone to a transmembrane Prolactin receptor. PRLR varies in size (short and long forms) with tissue source and species, from ~40 kDa to 100 kDa. The PRL-R consists of at least 3 separate domains: an extracellular region with 5 cysteines which contains the prolactin binding site, a single transmembrane domain and a cytoplasmic region, the length of which appears to influence ligand binding and regulate cellular function.

Glucagon-like peptide-1 (GLP-1) is derived from the transcription product of the proglucagon gene. The major source of GLP-1 in the body is the intestinal L cell that secretes GLP-1 as a guthormone. The biologically active forms of GLP-1 are: GLP-1-(7-37) and GLP-1-(7-36)NH2.
GLP-1 secretion by L cells is dependent on the presence of nutrients in the lumen of the small intestine. The secretagogues (agents that causes or stimulates secretion) of this hormone include major nutrients like carbohydrate, proteinand lipid. Once in the circulation, GLP-1 has a half life of less than 2 minutes, due to rapid degradation by the enzyme dipeptidyl peptidase-4.
GLP-1 possesses several physiological properties that make it a subject of intensive investigation as a potential treatment of diabetes mellitus. The known physiological functions of GLP-1 include: Increases insulin secretion from the pancreas in a glucose-dependent manner, decreases glucagon secretion from the pancreas, increases beta cells mass and insulin gene expression, inhibits acid secretion and gastric emptying in the stomach, decreases food intake by increasing satiety.

TUBG1 belongs to the tubulin superfamily. TUBG1 localizes to the centrosome and binds to microtubules to create the gamma-tubulin ring complex. TUBG1 facilitates the microtubule nucleation and is essential for microtubule formation and progression of the cell cycle.

Galectins are a family of animal lectins with an affinity for beta-galactosides. This family has at least 14 identified members. Galectins share similarities in the CRD (the carbohydrate recognition domain). Galectins are synthesized as cytosolic proteins. Though localized principally in the cytoplasm and lacking a classical signal peptide, galectins can also be stimulated to secretion by non-classical pathways or alternatively targeted to the nucleus. Galectins are involved in modulating cell-cell and cell-matrix interactions. Human Galectin-7 belongs to the prototypical Galectins containing a single CRD, which is initially identified in human epidermis as a monomer. The Galectin-7 expression is induced by tumor suppressor protein p53 and associated with apoptosis. Galectin-7 is a pro-apoptotic protein which functions intracellularlly upstream of JNK activation and mitochondrial cytochrome c release. The correlation of Galectin-7 with the UV-induced apoptosis of keratinocytes presents a critical mechanism in the maintenance of epidermal homeostasis. Human Galectin-7 is localized in both nucleus and cytoplasm.

Vaspin (visceral adipose-specific SERPIN), a newly identified adipokine, which is a member of serine protease inhibitor family. Vaspin is also a unique insulin sensitizing adipocytokine in obesity. A recent publication indicates that induction of human vaspin mRNA expression in adipose tissue is regulated in a fat depot-specific manner and could be associated with parameters of obesity, insulin resistance, and glucose metabolism.

Haptoglobin is a glycoprotein which is synthesized in the liver and circulates in the blood. Haptoglobin is produced typically by hepatocytes but also by other tissues: e.g. skin, lung, and kidney. It is a positive acute phase protein that binds free hemoglobin and removes it from the circulation to prevent kidney injury, and iron loss following hemolysis. The haptoglobin-hemoglobin complex is subsequently removed by the reticuloendothelial system (generally the spleen). As the reticuloendothelial system removes the haptoglobin-hemoglobin complex from the body, haptoglobin levels are reduced in hemolytic anaemias. In the course of binding hemoglobin, haptoglobin sequesters the iron inside hemoglobin, preventing iron-utilizing bacteria from benefitting from hemolysis.
Haptoglobin consists of two A- and two B-chains, connected by disulfide bonds. Three major haptoglobin phenotypes are known to exist (Hp 1-1, Hp 2-1, and Hp 2-2). Hp 1-1 is biologically the most effective in binding free hemoglobin and suppressing inflammatory responses associated with free hemoglobin. Hp 2-2 is biologically the least active, and Hp 2-1 is moderately active. Haptoglobin’s molecular mass ranges from 8-200 kDa.
Reduced levels can be seen in haemolysis and impaired liver function. High levels are a marker for acute or chronic inflammation. Ahaptoglobinemia or hypohaptoglobinemia are caused by mutations in the haptoglobin gene and/or its regulatory regions. Haptoglobin is also linked to diabetic nephropathy, the incidence of coronary artery disease in type 1 diabetes, Crohn's disease, inflammatory disease behavior, primary sclerosing cholangitis, susceptibility to idiopathic Parkinson's disease, and a reduced incidence of Plasmodium falciparum malaria.

Mediator Complex Subunit 20 (MED20) is a subunit of the Mediator complex, which is a multiprotein coactivator of RNA transcription that interacts with DNA-bound transcriptional activators, RNA polymerase II, and general initiation factors. The Mediator functions as a link to transmit information from gene-specific regulatory proteins to the basal RNA polymerase II transcription apparatus. Mediator is recruited to promoters by direct interactions with regulatory proteins and functions as a scaffold for the compilation of a functional preinitiation complex with RNA polymerase II and the general transcription factors.

Mediator complex subunit 4 (MED4) is a component of the Mediator complex, a coactivator involved in the regulated transcription of nearly all RNA polymerase II-dependent genes. MED4 is a component of the vitamin D receptor-interacting protein (DRIP) complex which functions as a nuclear receptor coactivator. The DRIP complex is able to activate nuclear receptors in a ligand-dependent manner. MED4 functions as a link to convey information from gene-specific regulatory proteins to the basal RNA polymerase II transcription apparatus. MED4 is recruited to promoters by direct interactions with regulatory proteins and serves as a scaffold for the assembly of a functional preinitiation complex with RNA polymerase II and the general transcription factors.

RGS17 weakens the signaling activity of G-proteins by binding to activated GTP-bound G alpha subunits and performing as a GTPase activating protein (GAP), increasing the rate of conversion of the GTP to GDP. This hydrolysis allows the G alpha subunits to bind G beta/gamma subunit heterodimers, creating inactive G-protein heterotrimers, which terminates the signal. RGS17 has a vital part in ending the signaling by mu opioid receptors and development of tolerance to opioid analgesic drugs.

Relaxin-3 (RLN3) belongs to the relaxin family. Relaxins are endocrine and autocrine/paracrine hormones. Relaxin, which is produced by the ovary, targets the mammalian reproductive system to ripen the cervix, elongate the pubic symphysis and inhibit uterine contraction. Unlike human Relaxins 1 and 2, Relaxin 3 does not seem to have a role in reproduction; however it is involved in stress response in the brain stem. RLN3 is the only known ligand for the G-protein-coupled receptor GPCR135, titled RXFP3. In addition, RLN3 binds the LGR7 (RXFP1) receptor, however with lower affinity than Relaxin-2. Even though binding of RLN3 to LGR7 increases intracellular cAMP, binding to GPCR135 suppresses cAMP accumulation, indicating coupling to Gi, Go, or Gz by this receptor.

Regulation of nuclear pre-mRNA domain-containing protein 1B (RPRD1B) interacts with phosphorylated C-terminal heptapeptide repeat domain (CTD) of the largest RNA polymerase II subunit POLR2A, and participates in dephosphorylation of the CTD. RPRD1B stimulates binding of RNA polymerase II to the CCDN1 promoter and to the termination region before the poly-A site but decreases its binding after the poly-A site. RPRD1B inhibits RNA polymerase II from reading through the 3' end termination site and may allow it to be drafted back to the promoter through promotion of the formation of a chromatin loop. In addition, RPRD1B enhances the transcription of several other cell cycle-related genes including CDK2, CDK4, CDK6 and cyclin-E but not CDKN1A, CDKN1B or cyclin-A. RPRD1B also promotes cell proliferation.

Von Willebrand Factor A Domain Containing 2 (VWA2) is an extracellular matrix protein containing vWA-like domains. VWA2 contains a signal peptide sequence, an N-terminal VWA domain connected to 2 additional tandem vWA domains by a cysteine-rich sequence and an EGF-like domain. Also, another EGF-like domain is located at the C-terminus. Expression of VWA2 is induced in stage II, III and IV colon cancers and colon adenomas and is considered a novel serum marker for the diagnosis of early-stage colon cancer.

IFN-gamma produced by lymphocytes activated by specific antigens or mitogens. IFN-gamma, in addition to having antiviral activity, has important immunoregulatory functions, it is a potent activator of macrophages, and has antiproliferative effects on transformed cells and it can potentiate the antiviral and antitumor effects of the type interferons.

IL11 is a member of the gp130 family of cytokines. These cytokines drive the assembly of multisubunit receptor complexes, all of which contain at least one molecule of the transmembrane signaling receptor IL6ST (gp130). IL-11 is shown to stimulate the T-cell-dependent development of immunoglobulin-producing B cells. It is also found to support the proliferation of hematopoietic stem cells and megakaryocyte progenitor cells.

Actin-related protein 2/3 complex subunit 2 (ARPC2), is a part of the Rho family of small GTPases and one of seven subunits of the human Arp2/3 protein complex. The Arp2/3 protein complex has been implicated in the control of actin polymerization in cells and has been conserved through evolution. Nevertheless, the exact role of the protein (the p34 subunit) has yet to be determined.

CAMP belongs to the antimicrobial peptide family, contains highly conserved N-terminal signal peptide, a cathelin domain and a structurally variable cationic antimicrobial peptide that produced by extracellular proteolysis from the C-terminus. CAMP has numerous functions besides the antimicrobial activity such as: cell chemotaxis, immune mediator induction and inflammatory response regulation.

Tubulointerstitial Nephritis Antigen Like 1 also known as TINAGL1 is similar in sequence to tubulointerstitial nephritis antigen, a secreted glycoprotein which is identified by antibodies in several types of immune-related tubulointerstitial nephritis. Three transcript variants encoding different isoforms are known for TINAGL1.

Mouse MIP-1 gamma is 75% identical in its amino acid compostion as compared to the rat specie. MIP-1 gamma is a CC chemokine localized in murine blood and a widespread range of murine tissues, without having an identified human homolog. MIP-1 gamma signals through the CCR1 receptor. MIP-1 gamma chemoattracts neutrophils and also inhibits colony formation of bone marrow myeloid immature progenitors. MIP-1 gamma has six cysteines including the four highly conserved cysteine residues present in CC chemokines.

GDNF Family Receptor Alpha 3 (GFRA3) belongs to the GDNF receptor family. GFRA3 creates a signaling receptor complex with RET tyrosine kinase receptor and binds the ligand, artemin (ARTN).

Prorelaxin H2 (RLN2) is a member of the insulin gene superfamily. This family which is produced by the ovary, targets the mammalian reproductive system to ripen the cervix, elongate the pubic symphysis and inhibit uterine contraction. It may also have other roles in boosting sperm motility, regulating blood pressure, controlling heart rate and releasing oxytocin and vasopressin. RLN2 is a peptide hormone linked to several therapeutically relevant physiological effects, including regulation of collagen metabolism and multiple vascular control pathways. The active form of the RLN2 protein consists of an A chain and a B chain linked by disulfide bonds.

Cystatins are a superfamily of cysteine proteinase inhibitors found in both plants and animals. They comprise a group of proteinase inhibitors, widely distributed in tissues and body fluids, and form tight complexes with cysteine proteases such as cathepsin B, H, L and S. Cystatin C, a secreted molecule of this family, is of interest from biochemical, medicine and evolutionary points of view. Cystatin C, with molecular weight of 13260 Da, is composed of 120 amino acids, lacks carbohydrate and has two disulfide bridges located near the carboxyl terminus. Cystatin C is increased in patients with malignant diseases, and is related to the insufficiency of renal function and appears to be a better marker than creatinine. On the other hand, low levels of cystatin C involve cause the breakdown of the elastic laminae and, subsequently, the atherosclerosis and abdominal aortic aneurysm.

Fibroblast Growth Factors (FGFs) comprise a family of at least eighteen structurally realted proteins that are involved in a multitude of physiological and pathological cellular processes, including cell growth, differentation, angiogenesis, wound healing and tumorgenesis. The biological activities of the FGFs are mediated by a family if type I transmembrane tyrosine kinases which undergo dimerization and autophosphorylation after ligand binding. Four distinct genes encoding closely related FGF receptors, FGFR-1to -4 are known. Multiple forms of FGFR-1 to -3 are generated by alternative splicing of the mRNAs. A frequent splicing event involving FGFR-1 and -2 results in receptors containing all three Ig domains, referred to as the alpha isoform, or only IgII and IgIII, referred to as the ? isoform. Only the alpha isoform has been identified for FGFR-3 and FGFR-4. Additional splicing events for FGFR-1 to -3, involving the C-terminal half of the IgIII domain encoded by two mutually exclusive alternative exons, generate FGF receptors with alternative IgIII domains (IIIb and IIIc). A IIIa isoform which is a secreted FGF binding protein containing only the N-terminal half of the IgIII domain plus some intron sequences has also been reported for FGFR-1. Mutations in FGFR-1 to -3 have been found in patients with birth defects involving craniosynostosis.

Hepatitis A virus cellular receptor 1 (HAVCR1) is a membrane receptor for both human hepatitis A virus (HHAV) and TIMD4. HAVCR1 is a type I trans-membrane structural glycoprotein located in the renal proximal tubule epithelial cells. HAVCR1 protein may be involved in the control of asthma and allergic diseases. The reference genome represents an allele which retains a MTTVP amino acid segment that presents defense against atopy in HHAV seropositive individuals.