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Signal-transducing adaptor protein 1 (STAP1) acts as a docking protein which operates downstream of Tec tyrosine kinase in B cell antigen receptor signaling. The STAP1 protein is directly phosphorylated by Tec in vitro where it partakes in a positive feedback loop, increasing Tec activity.

The La protein is a 47 kDa polypeptide that frequently acts as an autoantigen in systemic lupus erythematosus and Sjogren's syndrome patients. La is involved in various aspects of RNA metabolism, including binding and protecting 3-prime UUU(OH) elements of newly RNA polymerase III - transcribed RNA, processing 5-prime and 3-prime ends of pre-tRNA precursors, acting as an RNA chaperone, and binding viral RNAs linked to hepatitis C virus. It occurs in both the nucleus and the cytoplasm, where it assumes different roles. In the nucleus, La protein facilitates the production of tRNAs, acting as an RNA polymerase III (RNAP III) transcription factor by attaching to the U-rich 3'UTR of nascent transcripts, aiding in their folding and maturation. In the cytoplasm, La protein facilitates the translation of specific mRNAs, acting as a translation factor. As an RNA binding protein (RBP), La protein associates with subsets of mRNAs which contain a 5'-terminal oligopyrimidine (5'TOP) motif known to direct protein synthesis. The binding of La protein to particular classes of RNA molecules regulates their downstream processing, guards them from endonuclease digestion, and organizes their export from the nucleus. La/SS-B appears to be readily disposed to proteolysis, which results in many smaller (42kD, 320, and 270) nevertheless still immunoreactive polypeptides. La/SS-B antigen is strongly conserved across species. Anti-La/SS-B autoantibodies were originally found as precipitating autoantibodies in sera of Sjogren's Syndrome patients and referred to as SjT. Anti-La/SS-B precipitins are most frequently found in Sjogren's Syndrome, Systemic Lupus Erythematosus (SLE) and Subacute Cutaneous Lupus. Also, there seems to be a correlation between anti-La/SS-B and the absence of nephritis in SLE patients.

DKK1 is part of the dickkopf family. DKK1 is a secreted protein with 2 cysteine rich regions and takes part in embryonic development through its inhibition of the WNT signaling pathway. High levels of DKK1 in bone marrow plasma and peripheral blood is associated with the presence of osteolytic bone lesions in patients with multiple myeloma. Induction of DKK1 contributes to the pathological cascade triggered by beta-amyloid and is significantly involved in the development of tau phosphorylation.
DKK1 reduces the differentiation of osteoblastic precursor cells. DKK1 is an important member in multiple myeloma bone disease. DKK1 expression is reduced in human colon tumors, implying that DKK-1 plays a role as a tumor suppressor gene in this neoplasia; the Wnt/beta-catenin pathway is downregulated by the induction of DKK1 expression, a mechanism that is missing in colon cancer.

MVK is a member of the GHMP kinase family. Mevalonate is a vital mediator, and MVK an important early enzyme, in isoprenoid and sterol synthesis. MVK deficiency can result in gene mutation associated with Mevalonic aciduria, an illness which causes psychomotor retardation, failure to thrive hepatosplenomegaly, anemia and frequent febrile crises. Mutations in this gene also cause hyperimmunoglobulinaemia D and sporadic fever syndrome, in which the person suffers from recurrent episodes of fever related with lymphadenopathy, skin rash, gastrointestinal dismay and arthralgia.

ArsA Arsenite Transporter, ATP-Binding, Homolog 1 (ASNA1) is a part of the arsA ATPase family. ASNA1 is the human homolog of the bacterial arsA gene. ArsA ATPase is the catalytic component of a multisubunit oxyanion pump In E.coli, which is in charge for resistance to arsenicals and antimonials. ASNA1 is also a main component of a transmembrane domain (TMD) recognition complex (TRC) which is involved in the post-translational delivery of tail-anchored (TA) proteins from the cytosol to the endoplasmic reticulum (ER).

Eotaxin-2, also called MPIF2 & Ckb6, is a novel CC chemokine produced by activated monocytes and T lymphocytes. Eotaxin-2 selectively chemoattracts cells expressing CCR3 including eosinophils, basophils, Th2 T cells, mast cells, and certain subsets of dendritic cells. Furthermore, Eotaxin-2 inhibits the proliferation of multipotential hematopoietic progenitor cells. The mature protein, which includes C-terminal truncation, contains 78 amino acids (92 amino acids for the mouse homolog, without C-terminal truncation).
CCL24 functions as a chemotactic chemokine for resting t-lymphocytes, and eosinophils. CCL24 has lower chemotactic activity for neutrophils but none for monocytes and activated lymphocytes. CCL24 is a strong suppressor of colony formation by a multipotential hematopoietic progenitor cell line and binds to CCR3.

Nucleolin (NCL) which is a eukaryotic nucleolar phosphoprotein, involved in the synthesis and maturation of ribosomes. Nucleolin is the key nucleolar protein of growing eukaryotic cells. NCL is found linked with intranucleolar chromatin and pre-ribosomal particles. NCL induces chromatin decondensation by binding to histone H1. Nucleolin is assumed to have a role in pre-rRNA transcription and ribosome compilation. Nucleolin may also have a role in the process of transcriptional elongation. Nucleolin is located primarily in the dense fibrillar regions of the nucleolus. The Human NCL gene consists of 14 exons with 13 introns and spans approximately 11kb.

HEXA is the alpha subunit of the lysosomal enzyme beta-hexosaminidase which, combined with the cofactor GM2 activator protein, catalyzes the degradation of the ganglioside GM2, and other molecules having N-acetyl hexosamines terminus. The two subunits composing Beta-hexosaminidase, alpha and beta, belong to the glycosyl hydrolases family and are encoded by distinct genes. Alpha subunit gene mutations can cause Tay-Sachs disease (GM2-gangliosidosis type I).

EPCAM is a carcinoma-associated antigen and belongs to a family which includes at least 2 type I membrane proteins. The EPCAM protein has a role in embryonic stem cells proliferation and differentiation. EPCAM is used as a target for immunotherapy treatment of human carcinomas. EPCAM is expressed on most normal epithelial cells and gastrointestinal carcinomas and acts as a homotypic calcium-independent cell adhesion molecule. Epithelial cell adhesion molecules (EPCAM) can act as a physical homophilic interaction molecule between intestinal epithelial cells (IECs) and intraepithelial lymphocytes (IELs) at the mucosal epithelium for supplying immunological barrier as a first line of defense against mucosal infection. EPCAM gene mutations result in congenital tufting enteropathy.

TNFR1 belongs to the TNF-receptor superfamily. TNFR1 is a receptor for TNFSF2/TNF-alpha and homotrimeric TNFSF1/lymphotoxin-alpha.
There are 2 types of soluble TNF receptors: sTNFR-I and sTNFR-II, which act to neutralize the biological activities of TNF alpha and TNF beta. The levels of these soluble receptors seem to increase as a result of shedding of the extracellular domains of the membrane bound receptors. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.
TNFR1 is capable of signaling both cell survival and apoptosis. TNFR1-induced apoptosis requires 2 sequential signaling complexes. TNFR1 is capable of activating NF-kappaB, mediate apoptosis, and function as a regulator of inflammation. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNFR1 contributes to the induction of non-cytocidal TNF effects including anti-viral state and activation of the acid sphingomyelinase. Human TNFR1 has a major region which controls cell surface expression. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women.
Germline mutations of the extracellular domains of TNFR1 are linked to the autosomal dominant periodic fever syndrome. The impaired receptor clearance is believed to be a mechanism of the disease. Familial hibernian fever (FHF) is caused by defects in TNFRSF1A gene.

Thymic Stromal Lymphopoietin Receptor (TSLPR) is a member of the type I cytokine receptor family. TSLPR alongside the interleukin 7 receptor (IL7R) activate STAT3, STAT5, and JAK2 pathways, which is regulated processes such as cell proliferation and development of the hematopoietic system. Two transcript variants encoding dissimilar isoforms have been found for this gene. TSLPR is expressed in heart, skeletal muscle, kidney and adult and fetal liver.

The adipose tissue exclusively expresses and secretes Adiponectin (Acrp30). Acrp30 is involved in various physiological processes such as energy homeostasis, insulin sensitivity, hormonal processes, fatty acid metabolism and obesity.
Adiponectin circulates in the plasma. Decreased levels of Adiponectin are associated with insulin resistance and hyperinsulinemia, as seen in people with obesity insulin resistance, and diabetes type 2, whose plasma levels of adiponectin are reduced.
The modular structure of Acrp30 is comprised of N-terminal collagenous domain followed by a C-terminal globular domain.
Acrp30 also acts as a significant negative regulator in hematopoiesis and immune systems; it may be involved in ending inflammatory responses through its inhibitory functions. Adiponectin inhibits endothelial NF-kappa-b signaling through a cAMP-dependent pathway, it also inhibits TNF-alpha- induced expression of endothelial adhesion molecules.

Ostreolysin is extracted from Pleurotus ostreatus (oyster mushroom). It is a pore forming protein, which contains a lytic part to both cholesterol and sphingomyelin containing membranes. Because of their cholesterol content and the appearance of ostreolysin in the detergent resistant membranes, ostreolysin is cytotoxic towards the ovary cells of Chinese hamster. It seems that Ostreolysin spots a rich lipid cholesterol phase, presumably the liquid ordered phase.

Folate Receptor 1, also known as FOLR1, is a part of the folate receptor family whose members bind folic acid. FOLR1 binds to folate and reduced folic acid derivatives and facilitates transfer of 5-methyltetrahydrofolate and folate analogs into the cells. FOLR1 is either attaches to membranes through a glycosyl-phosphatidylinositol linkage or exists in a soluble form. FOLR1 is also needed for embryonic development and normal cell proliferation.

FSTL1 protein resembles follistatin, an ACTV-binding protein. FSTL1 is an autoantigen associated with rheumatoid arthritis and it holds an FS section, a follistatin-like sequence having 10 conserved cysteine residues.

RARRES2 is a secreted chemotactic protein that initiates chemotaxis through the ChemR23 G protein-coupled seven-transmembrane domain ligand. RARRES2 is upregulated by the synthetic retinoid tazarotene and found in a vast variety of tissues. RARRES2 acts as an adipokine, and is truncated on both termini from the proprotein. RARRES2 is structurally related to the cathelicidin precursors, cystatin C and kininogens. RARRES2 promotes calcium mobilization and chemotaxis of immature dendritic cells and macrophages. RARRES2 is secreted as a precursor of little biological activity, which requires proteolytic cleavage of its COOH-terminal domain to be exchangeed into a potent and highly specific agonist of ChemR23. RARRES2 signals via its receptor, ChemR23 (CMKLR1), as a positive regulator of adipocyte differentiation and metabolic function. The Chemerin receptor acts as a coreceptor for SIV and some primary HIV-1 strains. The Chemerin receptor has another ligand, called tazarotene-induced gene.

The epidermal growth factor receptor (EGF R) subfamily of receptor tyrosine kinases comprises four members: EGF R (also known as HER1, ErbB1 or ErbB), ErbB2 (Neu, HER-2), ErbB3 (HER-3), and ErbB4 (HER-4). All family members are type I transmembrane glycoprotein that has an extracellular domain which contains two cysteine-rich domains separated by a spacer region that is involved in ligand-binding, and a cytoplasmic domain which has a membrane-proximal tyrosine kinase domain and a C-terminal tail with multiple tyrosine autophosphorylation sites. The human EGF R gene encodes a 1210 amino acid (aa) residue precursor with a 24 aa putative signal peptide, a 621 aa extracellular domain, a 23 aa transmembrane domain, and a 542 aa cytoplasmic domain. EGF R has been shown to bind a subset of the EGF family ligands, including EGF, amphiregulin, TGF-a , betacellulin, epiregulin, heparin-binding EGF and neuregulin-2 in the absence of a co-receptor. Ligand binding induces EGF R homodimerization as well as heterdimerization with ErbB2, resulting in kinase activation, tyrosine phosphorylation and cell signaling. EGF R can also be recruited to form heterodimers with the ligand-activated ErbB3 or ErbB4. EGF R signaling has been shown to regulate multiple biological functions including cell proliferation, differentiation, motility and apoptosis. In addition, EGF R signaling has also been shown to play a role in carcinogenesis.

The FGFs are a family of more than 20 small (~17–26 kDa) secreted peptides. The initial characterization of these proteins focused on their ability to stimulate fibroblast proliferation. This mitogenic activity was mediated through FGF receptors (FGFRs) 1, 2, or 3. A fourth closely related tyrosine kinase receptor (FGFR4) was able to bind the FGFs but did not lead to a mitogenic response.
FGFs modulate cellular activity via at least 5 distinct subfamilies of high-affinity FGF receptors (FGFRs): FGFR-1, -2, -3, and -4, all with intrinsic tyrosine kinase activity and, except for FGFR-4, multiple splice isoforms, and FGFR-5, which lacks an intracellular kinase domain. There is growing evidence that FGFRs can be important for regulation of glucose and lipid homeostasis. The overexpression of a dominant negative form of FGFR-1 in ? cells leads to diabetes in mice, which thus implies that proper FGF signaling is required for normal ? cell function and glycemia maintenance. FGFR-2 appears to be a key molecule during pancreatic development. Moreover, FGFR-4 has been implicated in cholesterol metabolism and bile acid synthesis.
FGF-21 is preferentially expressed in liver, but an exact knowledge of FGF-21 bioactivity and its mode of action have been lacking to date. FGF-21 is a potent activator of glucose uptake on adipocytes, protects animals from diet-induced obesity when overexpressed in transgenic mice, and lowers blood glucose and triglyceride levels when therapeutically administered to diabetic rodents.

Inhibitor of Growth Family, Member 2 (ING2) belongs to the inhibitor of growth (ING) family. ING family members associate with and modulate the activity of histone acetyltransferase (HAT) and histone deacetylase (HDAC) complexes and serve in DNA repair and apoptosis. ING2 appears to be involved in p53/TP53 activation and p53/TP53-dependent apoptotic pathways, most likely by enhancing acetylation of p53/TP53. ING2 is a component of an mSin3A-like corepressor complex, which is probably involved in deacetylation of nucleosomal histones. ING2 activity is modulated by binding to phosphoinositides (PtdInsPs).

Chemokine (C-C motif) ligand 2 (CCL2) is a small cytokine belonging to the CC chemokine family that is also known as monocyte chemotactic protein-1 (MCP-1). It is found at the site of tooth eruption and bone degradation. In the bone, CCL2 is expressed by mature osteoclasts and osteoblasts and is under the control of nuclear factor ?B (NF?B). CCL2 recruits immune cells, such as monocytes, to sites of tissue injury and infection. This chemokine is produced as a protein precursor containing signal peptide of 23 amino acids and a mature peptide of 76 amino acids. It is a monomeric polypeptide, with a molecular weightof approximately 13kDa. As with many other CC chemokines, CCL2 is located on chromosome 17 in humans. The cell surface receptors that bind CCL2 are CCR2 and CCR5.

FCER2, or Fc epsilon RII, is a receptor for IgE with low affinity, which is critical to regulation of IgE levels. IgE is an antibody isotype that attached to allergy and resistance to parasites. FCER2 is a C-type lectin, contrary to many of the receptors for antibodies. FCER2 is located on activated macrophages, mature B cells, follicular dendritic cells, platelets and eosinophils.

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 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.