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Calretinin is an intracellular calcium-binding protein belonging to the troponin C superfamily characterized by a structural motif described as the EF-hand domain. The immunohistochemical detection of calretinin in developing cerebellum is restricted to the later stages indicated by weak staining from week 21 of gestation, in Purkinje and basket cells and in neurons of the dentate nucleus. The intensity of staining increases as the cerebellum matures. In tumors, calretinin has been detected in mesotheliomas and some pulmonary adenocarcinomas.

CYR61 is a growth factor-inducible, immediate-early gene that has multifaceted activities in various cancers. CYR61 is a secreted, cysteine-rich, binding protein which is encoded by a growth factor-inducible immediate-early gene. Acting as an extracellular, matrix-associated signaling molecule, CYR61 promotes the adhesion of endothelial cells through interaction with integrin and enhances growth factor-induced DNA synthesis in the same cell type.

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. Galectin-8 is a tandem-repeat-type member of the galectin family, consisting of 2 CRDs attached by a linker peptide. Galectin-8 is greatly expressed in lung carcinomas, a number of forms of prostate carcinomas, in addition to other tumor cells. Galectin-8 attaches to a subset of cell surface integrins to modulate ECM-integrin interactions. Once immobilized, Galectin-8 promotes cell adhesion by ligation and clustering of cell surface integrin receptors. On the other hand, as a soluble ligand, Galectin-8 can inhibit cell adhesion.

SIVA1, also referred to asApoptosis regulatory protein Siva isoform 1, is a death domain-containing proapoptotic protein. It is known as glucocorticoid-induced TNFR family-related gene, and also as an intracellular ligand of CD27, which are both members of the TNFR family expressed on lymphoid cells. There isn’t much known about the signalling pathway underlying the Siva-induced apoptosis.SIVA1 expression is modulated in multiple pathological processes.

ULBP2 is a member of the MHC class I family. ULBP2 is ligand for the NKG2D receptor, composed with at least ULBP1 and ULBP3. ULBPs promote multiple signaling pathways in primary NK cells, triggering the production of cytokines and chemokines. Binding of ULBPs ligands to NKG2D encourages calcium mobilization and activation of the JAK2, STAT5, ERK and PI3K kinase/Akt signal transduction pathway. In CMV infected cells, ULBP2 cooperates with soluble CMV glycoprotein UL16. This cooperation is blocked with the NKG2D receptor, providing a mechanism in which CMV infected cells can escape the immune system. Additionally, UL16 causes ULBP2 to be held in the ER and cis-Golgi apparatus so that it does not reach the cell surface.

FKBPL is related to the immunophilin protein family, which take part in immunoregulation and regular cellular processes involving protein folding and trafficking. FKBPL has an important function in the induced radioresistance and participates in the control of the cell cycle. FKBPL has a role in cellular response to stress. FKBPL interacts with Hsp90, glucocorticoid receptor and dynamitin and is involved in signalling, like other FKBPs.

Nephroblastoma Overexpressed (NOV) which is encoded by the NOV gene is a part of the CCN (CTGF/CYR61/NOV) family. NOV takes part in reducing tumorgenicity and proliferation of certain cancer cell lines. NOV interacts with numerous proteins and is involved in both internal and external cell signaling. NOV is expressed in particular tumors, including Wilm’s tumor and most nephroblastomas and is also exerts proangiogenic activities.

ZMAT3 is a protein with a nuclear localization signal and 3 zinc finger domains. The mRNA and the protein of this gene are upregulated by wildtype p53. When overexpressed, ZMAT3 can produce tumor cell growth, indicating that ZMAT3 takes part in the p53-dependent growth regulatory pathway. Alternative splicing of ZMAT3 produce two transcript variants encoding two isoforms differing in only one amino acid.

S100A13 is a member of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 family members are localized in the cytoplasm and/or nucleus of a wide range of cells, and are involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. S100A13 is extensively expressed in various types of tissues with an elevated expression level in the thyroid gland. In smooth muscle cells, S100A13 co-expresses with other family members in the nucleus and in stress fibers, suggesting diverse functions in signal transduction.

Alpha 1-microglobulin (A1M) is a lipocalin superfamily member (kernal lipocalins). A1M is a low molecular weight protein component of plasma. A1M is distributed in plasma and extravascular compartments of all organs. Alpha-1 Microglobulin is found in mammals, birds, amphibians and fish. The primary sites of A1M synthesis are the liver and the kidney. Around the opening of the lipocalin pocket three lysyl residues are situated; those residues carry yellow-brown modification derived from the binding and degradation of heme and kynurenin (a tryptophan metabolite). A1-Microglobulin’s reductase and dehydrogenase have broad biological substrate specificity properties due to its’ free cysteine side-chain which is located in a flexible loop. Alpha-1-microglobulin is glycosylated by three separate carbohydrate chains: two complex carbohydrates which are N-linked to asparagines at residues 17 and 96, and the other simple carbohydrate which is O-linked to threonine at position 5. The carbohydrates comprise 22% of the total molecular mass of the protein. The glycosylation varies between species.
A1M exists in two forms- a free form and complexed to other macromolecules: in humans- complexed to immunoglobulin A (IgA), in rat- complexed to alpha-1-inhibitor-3. Free A1M is exceptionally heterogeneous in charge (therefore also known as protein HC), and is found tightly linked to a chromophore. The free Alpha-1-microglobulin is a monomeric protein composed of one 188 residue polypeptide and contains three cysteines, two of which (residues 75 and 173) form a conserved intra-molecular disulphide link. The chromophoric group is covalently bound to the free cysteine residue at position 34. A1M binds retinol as a major ligand, but this is probably distinct from its covalent chromophore.
Half of all human plasma A1M (approximately 0.03mg/ml) forms a 1:1 complex with about 5% of plasma immunoglobulin A. The resulting macromolecular complexes’ molecular weight is 200000, and a plasma concentration of 0.3mg/ml. The complex can exhibit both antibody activity and affect many of the biological actions of free Alpha-1-microglobulin.
Alpha-1-microglobulin was first discovered in pathological human urine.
It was suggested that A1M might be involved in tissue defense against reactive oxygen species, oxidation by heme and kynurenin. Evidence also suggests that A1M functions in the regulation of the immune system. Other functions include inhibition of stimulation of cultured lymphocytes by protein antigens; induction of cell division of lymphocytes, a mitogenic effect that can either be enhanced or inhibited by the action of other plasma components; inhibition of neutrophil granulocyte migration in vitro; and inhibition of chemotaxis.

MAK16 is a member of the MAK16 family.

Adipocyte fatty acid binding protein FABP4 is a 15 kDa member of the intracellular fatty acid binding protein (FABP) family, which is known for the ability to bind fatty acids and related compounds (bile acids or retinoids) in an internal cavity. FABP4 is expressed in a differentiation-dependent fashion in adipocytes and is a critical gene in the regulation of the biological function of these cells.
In mice, targeted mutations in FABP4 provide significant protection from hyperinsulinemia and insulin resistance in the context of both dietary and genetic obesity. Adipocytes obtained from FABP4-deficient mice also have reduced efficiency of ipolysis in vitro and in vivo, and these mice exhibited moderately improved systemic dyslipidemia. Recent studies also demonstrated FABP4 expression in macrophages upon differentiation and activation. In these cells, FABP4 modulates inflammatory responses and cholesterol ester accumulation, and total or macrophage-specific FABP4 deficiency confers dramatic protection against atherosclerosis in the apoE-/- mice. These results indicate a central role for FABP4 in the development of major components of the metabolic syndrome through its distinct actions in adipocytes and macrophages.

SCGN is a secreted calcium-binding protein which is found in the cytoplasm. It is related to calbindin D-28K and calretinin. Secretagogin is involved in KCL-stimulated calcium flux and cell proliferation.
Secretagogin plays a role in human non-functional pituitary adenomas.

PEBP1 (Phosphatidylethanolamine binding protein 1) belongs to the phosphatidylethanolamine-binding protein family and a serine protease inhibitor that inhibits thrombin, neuropsin. PEBP1 plays a key modulatory part in several protein kinase signaling cascades. PKC phosphorylates PEBP1, resulting in the release of Raf-1 and activation of MEK and ERK. PEBP1 is expressed in many tissues and implicated in the regulation of such physiological processes as membrane biosynthesis, spermatogenesis, neural development, and metastasis suppression.
PEBP1 binds ATP, opioids and phosphatidylethanolamine, however it has lower affinity for phosphatidylinositol and phosphatidylcholine. PEBP1 may also be involved in the function of the presynaptic cholinergic neurons of the CNS. PEBP1 increases the production of choline acetyltransferase although not acetylcholinesterase. Furtheremore, PEBP1 functions in potentially sequestering toxic compounds, including locostatin which may have harmful effects on cells.
Loss of PEBP1 expression may have a significant role as prognostic marker in Gastrointestinal stromal tumors. In addition, PEBP1 is found differentially expressed in the Wernicke's Area from schizophrenia patients. PEBP1 is also, an invasion suppressor protein in nasopharyngeal carcinoma.

Zinc-alpha-2-glycoprotein (ZAG) is found in body fluids such as serum, sweat, and seminal and breast cyst fluids. It is identical in amino acid sequence to tumor-derived lipid mobilizing factor (LMF), a protein associated with the dramatic loss of adipose body stores in cancer cachexia, and has been shown to stimulate lipolysis by adipocytes in vivo and in vitro. A role for ZAG has been proposed in the regulation of body weight, and age-dependent changes in genetically influenced obesity, and also it regulates melanin production by normal and malignant melanocytes. It has also recently been classified as a novel adipokine in that it is produced by both white and brown fat adipocytes and may act in a local autocrine fashion in the reduction of adiposity in cachexia. Controlling ZAG/LMF's activity could be life-saving in the management of certain cancers and other cachexiainducing conditions, and its possible normal role in body fat store homeostasis is deserving of understanding in its own right. ZAG exhibits a class I major histocompatibility complex (MHC) fold but is a soluble protein rather than being anchored to plasma membranes and does not associate with alpha-2-microglobulin in humans. Like antigen-presenting MHC class I proteins, ZAG has an open apical groove, and X-ray crystallography of human derived ZAG revealed an unidentifiable electron density in a similar position to that occupied by antigenic peptides in classical MHC proteins and glycolipids in isoforms of CD1. This presumptive ligand is not a peptide, and the groove is too small to hold a glycolipid such as is presented by CD1 isoforms. By analogy with all other MHC class I-related proteins that have an open apical groove [some do not ], occupancy by a ligand is probably crucial to ZAG's biological function. Despite all of the structural and biochemical evidence that ZAG binds a ligand, none has so far been found by extraction from protein isolated from biological fluids. This difficulty could be because the ligand is labile, heterogeneous, or readily lost during purification procedures. Knowing more about how ZAG interacts with the compounds it has been found to bind, both natural and artificial, will inform searches for the elusive ligand(s) and its/their role in ZAG's signaling function.

Zinc-alpha-2-glycoprotein (ZAG) is found in body fluids such as serum, sweat, and seminal and breast cyst fluids. It is identical in amino acid sequence to tumor-derived lipid mobilizing factor (LMF), a protein associated with the dramatic loss of adipose body stores in cancer cachexia, and has been shown to stimulate lipolysis by adipocytes in vivo and in vitro. A role for ZAG has been proposed in the regulation of body weight, and age-dependent changes in genetically influenced obesity, and also it regulates melanin production by normal and malignant melanocytes. It has also recently been classified as a novel adipokine in that it is produced by both white and brown fat adipocytes and may act in a local autocrine fashion in the reduction of adiposity in cachexia. Controlling ZAG/LMF's activity could be life-saving in the management of certain cancers and other cachexiainducing conditions, and its possible normal role in body fat store homeostasis is deserving of understanding in its own right. ZAG exhibits a class I major histocompatibility complex (MHC) fold but is a soluble protein rather than being anchored to plasma membranes and does not associate with alpha-2-microglobulin in humans. Like antigen-presenting MHC class I proteins, ZAG has an open apical groove, and X-ray crystallography of human derived ZAG revealed an unidentifiable electron density in a similar position to that occupied by antigenic peptides in classical MHC proteins and glycolipids in isoforms of CD1. This presumptive ligand is not a peptide, and the groove is too small to hold a glycolipid such as is presented by CD1 isoforms. By analogy with all other MHC class I-related proteins that have an open apical groove [some do not ], occupancy by a ligand is probably crucial to ZAG's biological function. Despite all of the structural and biochemical evidence that ZAG binds a ligand, none has so far been found by extraction from protein isolated from biological fluids. This difficulty could be because the ligand is labile, heterogeneous, or readily lost during purification procedures. Knowing more about how ZAG interacts with the compounds it has been found to bind, both natural and artificial, will inform searches for the elusive ligand(s) and its/their role in ZAG's signaling function.

EBAG9 is a type III transmembrane protein that is primarily located in the Golgi. EBAG9 is a tumor-associated antigen that is expressed at high frequency in a variety of cancers, such as advanced breast and prostate cancers. while the EBAG9 acts to inhibit the growth of receptor-binding cells and induced apoptosis of immune cells, cancer cells may evade immune surveillance. Thus immunodetection of EBAG9 expression can be a negative prognostic indicator. EBAG9 promotes progression of bladder cancer. In rheumatoid arthritis, the deficiency of EBAG9 induces CTL infiltration through failure to evade immune attack, therefore leading to apoptosis of the synovial lining cells. EBAG9 is involved in controlling exocytosis processes. EBAG9 expression plays a role in the progression of oral squamous cell carcinoma. EBAG9 plays a specific role in premature stages of breast carcinogenesis.

S100b is a member of the S100 family of proteins which are a family of EF-hand calcium binding proteins that exist mostly as dimers of the 20 currently identified individual S100 monomers. The S100B homodimer is expressed in cells of the central nervous system, glial cells and in certain peripheral cells e.g. Schwann cells, melanocytes, adipocytes and chondrocytes. S100 proteins are localized either in the cytoplasm or the nucleus of a wide range of cells. S100 proteins are involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. There are at least 13 members in the S100 gene family, which are located as a cluster on chromosome 1q21; however, S100b is located at 21q22.3. The determination of S100B in serum levels may be used to monitor the extent of brain injury and malignant melanoma. S100b proteins may have a role in Neurite extension, proliferation of melanoma cells, stimulation of Ca2+ fluxes, inhibition of PKC-mediated phosphorylation, astrocytosis and axonal proliferation, and inhibition of microtubule assembly. Chromosomal rearrangements and altered expression of the S100b gene are implicated in several neurological, neoplastic, and other types of diseases, including Alzheimer's disease, Down's syndrome, epilepsy, amyotrophic lateral sclerosis, melanoma, and type I diabetes.

GDP-fucose protein O-fucosyltransferase 1 (POUFUT1), belongs to the glycosyltransferase O-Fuc family. POUFUT1 encodes a member of the glycosyltransferase O-Fuc family and Expressed mainly in pancreas, kidney, lung, heart, brain, liver, placenta and skeletal muscle.POUFUT1 adds O-fucose through an O-glycosidic linkage to Preserve serine or threonine residues in the epidermal growth factor-like repeats of a number of cell surface and emitted proteins. POUFUT1 is involved in ligand-induced receptor signaling. Alternative splicing of this gene results in 2 transcript variants encoding different isoforms.POFUT1 participates in Notch signaling, as Notch ligands can use as POFUT1 substrates.

Otubain 1 (OTUB1) belongs to the ovarian tumor (OUT) superfamily of predicted cysteine proteases and inhibits cytokine gene transcription in the immune system through its interaction with a ubiquitin protease and E3 ubiquitin ligase. OTUB1 is a highly specific ubiquitin iso-peptidase, it cleaves ubiquitin from branched poly-ubiquitin chains but not from ubiquitinated substrates. OTUB1 is believed to work in specific ubiquitin-dependent pathways, possibly by providing an editing function of polyubiquitin chain growth. OTUB1 is a hydrolase that removes conjugated ubiquitin from proteins in vitro and may therefore have a significant regulatory role in the level of protein turnover by preventing degradation. Additionally, OTUB1 is a regulator of T-cell anergy, a phenomenon that occurs when T-cells are rendered impassive to antigen re-challenge and no longer respond to their cognate antigen. OTUB1 acts via its interaction with RNF128/GRAIL, which is an essential inductor of CD4 T-cell anergy.

MMAB protein catalyzes the last step in the conversion of vitamin B(12) into adenosylcobalamin (AdoCbl), a vitamin B12 containing coenzyme for methylmalonyl-CoA mutase(MCM). Decreased MMAB activity leads to the inherited disorder vitamin B12 dependent methylmalonic aciduria linked to the cblB complementation group.

SAR1A is a member of the small GTPase superfamily. SAR1A is a vital component of COPII vesicle coats involved in export of cargo from the ER (Endoplasmic Reticulum). The GTPase activity of SAR1A serves as a molecular switch to control protein-protein and protein-lipid interactions which dictate vesicle budding from the ER. SAR1A, while GDP-bound interacts with the membrane-bound exchange factor Sec12 and trades its bound GDP for GTP. SAR1A is also involved in the transport from the ER to the Golgi apparatus. SAR1A is required to maintain SEC16A localization at distinct locations on the ER membrane possibly by preventing its dissociation. SAR1A-GTP-dependent compilation of SEC16A on the ER membrane creates a structured scaffold defining endoplasmic reticulum exit sites.

Interleukin-18 Binding Protein (IL18BP) serves as an inhibitor of the proinflammatory cytokine, IL18. IL18BP binds IL18, inhibits the binding of IL18 to its receptor, and consequently inhibits IL18-induced IFN-gamma production, resulting in reduced T-helper type 1 immune responses. The IL18BP protein is constitutively expressed and secreted in mononuclear cells. Elevated levels of IL18BP protein are detected in the intestinal tissues of patients with Crohn's disease.