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Cytokeratin 17 also known as KRT17 is a type I cytokeratin. KRT17 is found in nail beds, hair follicles, sebaceous glands, and other epidermal appendages. Mutations in KRT17 lead to Jackson-Lawler type pachyonychia congenita and steatocystoma multiplex. KRT17 takes part in the formation and maintenance of a variety of skin appendages, particularly in determining shape and orientation of hair. KRT17 also modulates the function of TNF-alpha in the precise context of hair cycling. Moreover, KRT17 regulates protein synthesis and epithelial cell growth all through binding to the adapter protein SFN and by stimulating Akt/mTOR pathway.

LZIC is a member of the CTNNBIP1 family. LZIC protein is universally expressed, with largest levels in kidney and up-regulated in various cases of gastric cancers. LZIC has no interaction with CTNNB1.

RAC1 is a GTPase which belongs to the RAS superfamily of small GTP-binding proteins. Members of this superfamily appear to regulate a diverse array of cellular events, including the control of cell growth, cytoskeletal reorganization, and the activation of protein kinases. RAC-1 regulates the actin cytoskeleton but also other cellular processes. RAC1 have been shown to be involved in the regulation of cell-cell adhesion.

Excess adiposity is the most important risk in the development of type 2 diabetes mellitus (T2DM). Adipose tissue produces several proteins (adipocytokines) such as leptin, adiponectin, resistin, tumor necrosis factor-a, and IL-6, that modulate sensitivity and appear to play an important role in the pathogenesis, diabetes, dyslipidemia, inflammation, and atherosclerosis. Visfatin, also known as pre-B cell colony-enhancing factor (PBEF), is a cytokine that is highly expressed in visceral fat and was originally isolated as a secreted factor that synergizes with IL-7 and stem cell factors to promote the growth of B cell precursors. Visfatin homologs have been identified in carp, invertebrate mollusks, and bacteria, as well as in vertebrates, including humans and the mouse. It has been postulated to play a role in innate immunity.
Visfatin exerts mimetic effects that are dose-dependent and quantitatively similar to stimulating muscle and adipocyte glucose transport, and in inhibiting hepatocyte glucose production. Intravenous injection of recombinant visfatin in mice decreased plasma glucose in a dose-dependent fashion. In keeping with its mimetic effects, visfatin was as effective in reducing hyperglycemia in deficient diabetic mice. Visfatin was also found to be bound to and activate receptor, causing receptor phosphorylation and the activation of downstream signaling molecules. However, visfatin did not compete for binding to the receptor, indicating that the two proteins were recognized by different regions of the receptor. Thus, visfatin might play a role in glucose homeostasis and dysregulation in biosynthesis or signal transduction, and might contribute to the pathogenesis of diabetes.

Bronchoalveolar lavage fluid from mice with experimentally induced allergic pulmonary inflammation contains a novel 9.4 kDa cysteine-rich secreted protein, RELM-alpha (FIZZ1, found in inflammatory zone). RELM-alpha is a secreted protein that has a restricted tissue distribution with highest levels in adipose tissue stroma. Murine RELM-alpha (FIZZ1) is the founding member of a new gene family including two other murine genes expressed, respectively, in intestinal crypt epithelium (RELM-beta) and white adipose tissue (Resistin), and two related human genes.
RELMalpha inhibits the differentiation of 3T3-L1 preadipocytes into adipocytes but has no effect on proliferation of 3T3-L1 preadipocytes. RELMalpha is able to form heterooligomers with resistin but not RELMbeta. Since RELMalpha is expressed by adipose tissue and it is a secreted factor, our findings suggest that RELMalpha may be involved in the control of the adipogenesis as well as in the process of muscle differentiation.
In the lung, RELM-alpha is induced by hypoxia and was renamed as hypoxia-induced mitogenic factor (HIMF). HIMF strongly activated Akt phosphorylation. The phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 (10 micromol/L) inhibited HIMF-activated Akt phosphorylation. It also inhibited HIMFstimulated RPSM proliferation. Thus, the PI3K/Akt pathway, at least in part, mediates the proliferative effect of HIMF. Further studies showed that HIMF had angiogenic and vasoconstrictive properties. HIMF increased pulmonary arterial pressure and vascular resistance. Further studies suggest that HIMF regulates apoptosis and may participate in lung alveolarization and maturation.

Kallikrein-3 (KLK3) is a part of the kallikrein-related peptidase family. Kallikreins are a subgroup of serine proteases having various physiological functions. Numerous kallikreins take part in carcinogenesis and some may be prospective cancer and other disease biomarkers. Kallikrein-3 is 1 of the 15 kallikrein subfamily members located in a cluster on chromosome 19 and is a protease present in seminal plasma. KLK3 hydrolyzes semenogelin-1 consequently leading to the liquefaction of the seminal coagulum. KLK3 acts normally in the liquefaction of seminal coagulum, probably by hydrolysis of the high molecular mass seminal vesicle protein. Serum level of the KLK3 protein, called PSA in the clinical setting, is beneficial in the diagnosis and monitoring of prostatic carcinoma.

Killer cell immunoglobulin-like receptor 2DL4, also known as KIR2DL4 is part of the killer cell Ig-like receptor (KIR) family. KIR proteins with the long cytoplasmic domain transduce inhibitory signals through an immune tyrosine-based inhibitory motif (ITIM), whereas KIR proteins which contain the short cytoplasmic domain, lack the ITIM motif and as a substitute associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals. KIR2DL4 stimulates NK cells to produce IFN-gamma and stimulation with IL-2 upregulates cell surface expression on CD56dimcells and leads to the inhibition of the cytolytic NK cell function.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is wilyde used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

Ara h 2 comprises of 2 isoforms: Ara h 2.0101 and Ara h 2.0201. Ara h 2.0201 is the most important peanut allergen which binds IgE. Ara h 2.0201 is a Weak inhibitor of trypsin and is a conglutin storage protein which accounts together with Ara h 6.0101 for the majority of the IgE immune response.

ASF1A is part of the H3/H4 family of histone chaperone proteins corresponding to the anti-silencing function-1 gene in yeast. ASF1A is an important element of the histone donor complex that functions in nucleosome assembly. ASF1A interacts with histones H3 and H4, and functions together with a chromatin assembly factor during DNA replication and repair. Deletion of ASF1A in yeast and Drosophila confers sensitivity to various DNA damaging agents and inhibitors of DNA replication, increases genomic instability and sister chromatid exchange, and activates the DNA damage checkpoint.

PPIF is a part of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIF accelerates the folding of proteins. It catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides. PPIF is key component of the mitochondrial permeability transition pore in the inner mitochondrial membrane. Activation of this pore is thought to be involved in the induction of apoptotic and necrotic cell death.

CD68 encodes a 110-kD transmembrane glycoprotein that is highly expressed by human monocytes and tissue macrophages. It is a member of the lysosomal/endosomal-associated membrane glycoprotein (LAMP) family. The protein primarily localizes to lysosomes and endosomes with a smaller fraction circulating to the cell surface. It is a type I integral membrane protein with a heavily glycosylated extracellular domain and binds to tissue- and organ-specific lectins or selectins. The protein is also a member of the scavenger receptor family. Scavenger receptors typically function to clear cellular debris, promote phagocytosis, and mediate the recruitment and activation of macrophages. Alternative splicing results in multiple transcripts encoding different isoforms.

XCL1 is a small cytokine belongs to the XC chemokine family that is also known as lymphotactin. XCL1 is found in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

Exedin-4 Recombinant is a like peptide-1 receptor agonist. The native hormone is produced in the gut of Gila monster Heloderma suspectrum (a type of reptile found in the desert) that stimulates production without causing threateningly low blood sugar, which can occur after using some anti-diabetes products. Recently, researchers used extracted saliva from gila monsters to create an unprecedented breakthrough in Diabetes Type 2 treatment. Unlike other products taken for type 2 diabetes, Exedin-4 has not been linked with weight gain and actually resulted in weight loss, according to the researchers. Exedin-4 enhances glucose-dependant secretion, suppresses inappropriately elevated secretion and slows gastric emptying in vivo. It also promotes B-cell proliferation and neogenesis in vitro and in animal models. Exedin-4 stimulates an increase in acinar cAMP, without stimulating the release of amylase.

SARS Coronavirus is an enveloped virus containing three outer structural proteins, namely the membrane (M), envelope (E), and spike (S) proteins. Spike (S)-glycoprotein of the virus interacts with a cellular receptor and mediates membrane fusion to allow viral entry into susceptible target cells. Accordingly, S-protein plays an important role in virus infection cycle and is the primary target of neutralizing antibodies.It has recently been shown that SARS is caused by a human coronavirus. Human coronaviruses are the major cause of upper respiratory tract illness in humans, such as the common cold. Coronaviruses are positive-stranded RNA viruses, featuring the largest viral RNA genomes known to date (27-31 kb). The first step in coronavirus infection is binding of the viral spike protein, a 139-kDa protein, to certain receptors on host cells. The spike protein is the main surface antigen of the coronavirus. The most prominent protein in the culture supernatants infected with SARS virus is a 46 kDa nucleocapsid protein. This suggests that the nucleocapsid protein is a major immunogen that may be useful for early diagnostics.

Chemokine (C-C motif) ligand 13 (CCL13 / MCP-4) is a small cytokine belonging to the CC chemokine family. The MCP-4 gene is located on human chromosome 17 within a large cluster of other CC chemokines. MCP-4 induces chemotaxis in monocytes, eosinophils, T lymphocytes, and basophils by binding cell surface G-protein linked chemokine receptors such as CCR2, CCR3 and CCR5. Activity of the MCP-4 chemokine has been implicated in allergic reactions such as asthma. MCP-4 can be induced by the inflammatory cytokines interleukin-1 and TNF-a.

SPARC, an acronym for “secreted protein, acidic and rich in cysteine”, is also known as osteonectin or BM-40. It is the founding member of a family of secreted matricellular proteins with similar domain structure. The 303 amino acid, 43 kDa protein contains a 17 aa signal sequence, an N-terminal acidic region that binds calcium, a follistatin domain containing Kazal-like sequences, and a C-terminal extracellular calcium (EC) binding domain with two EF-hand motifs. SPARC is produced by fibroblasts, capillary endothelial cells, platelets and macrophages, especially in areas of tissue morphogenesis and remodeling. SPARC shows context-specific effects, but generally inhibits adhesion, spreading and proliferation, and promotes collagen matrix formation. For endothelial cells, SPARC disrupts focal adhesions and binds and sequesters PDGF and VEGF. SPARC is abundantly expressed in bone, where it promotes osteoblast differentiation and inhibits adipogenesis.

Inhibins are dimeric peptide hormones produced by female ovarian granulose cells and male Sertoli cells as well as a variety of other tissues. Inhibins have two isoforms, A and B, with the same alpha subunit but different beta subunits. Inhibin A is a dimer of alpha and beta A subunits, inhibin B is a dimer of alpha and beta B subunits.
Inhibins are thought to inhibit the production of follicle-stimulating hormone (FSH) by the pituitary gland. In addition, Inhibins are also thought to play a role in the control of gametogenesis, and embryonic and fetal development.

SLAMF7 belongs to the CS2 family of cell surface receptors. SLAMF7 is a single-pass type 1 membrane protein, SLAMF7 Isoform 1 mediates NK cell activation via aSH2D1A-independent extracellular signal-regulated ERK-mediated pathway. SLAMF7 functions in lymphocyteadhesion. Furthermore, SLAMF7 can exert activating of inhibitory influences on cells of the immune system depending on cellular context as well as the availability of effector proteins.

RERG is a 199 amino acid protein which localizes in the cytoplasm and is a member of the Ras subfamily of small GTPases. RERG is expressed in the pancreas, liver, skin, lung, brain, kidney and heart tissue. RERG is a vital mediator of diverse cell signaling pathways, including those leading to cell proliferation, cytoskeletal organization and secretion.

LIN7B (VELI2), is a member of the Velis family. Velis family contains minor synaptic proteins which interact with other proteins at the post-synaptic density (PSD) of neuronal synapses. Velis which contain the PDZ motif, participate in recruiting cell adhesion molecules, receptors, and channels. Lin7B protein is ubiquitously expressed with a high expression in the brain, liver, and testis. Lin7B localizes at the synaptic junctions in neurons, bind to CASK, which is a neurexin-binding protein highly concentrated in synapses, and Mint1, a binding partner with a vesicle trafficking protein.

Connective Tissue Growth Factor belongs to the CCN family of proteins. The CCN family presently consists of six members in human also known as: Cyr61 (Cystein rich 61), CTGF (Connective Tissue Growth Factor), Nov (Nephroblastoma Overexpressed gene), WISP-1, 2 and 3 (Wnt-1 Induced Secreted Proteins). The CCN genes encode secreted proteins associated with the Extracellular Matrix (ECM) and cell membrane. CCN proteins are matricellular proteins which are involved in the regulation of various cellular functions including: proliferation, differentiation, survival, adhesion and migration. They are expressed in derivatives of the three embryonic sheets and are implicated in the development of kidney, nervous system, muscle, bone marrow, cartilage and bone. During adulthood, they are implicated in wound healing, bone fracture repair, and pathologies such as: fibrosis, vascular ailments and tumorigenesis.
Full length secreted CCN proteins can show an antiproliferative activity, whereas truncated isoforms are likely to stimulate proliferation and behave as oncogenes. The full length protein consists of four modulesModule I shares partial identity with the N-terminal part of the Insulin-like Growth Factor Binding Proteins (IGFBPs).
Module II includes a stretch of 70amino acid residues – which shares sequence identity with the Von Willebrand Factor Type C repeat (VWC).
Module III contains sequences sharing identity with the Thrombospondin type 1 repeat (TSP1) (WSXCSXXCG), which is thought to be implicated in the binding of sulfated glycoconjugates and to be important for cell adhesion. Module IV, also designated CT, is encoded by exon5. It is the leasts conserved one of the four domains at the level of nucleotide sequence, but it appears to be critical for several of the biological functions attributed to the CCN proteins. Module IV resembles the CT domain of several extracellular protein including, Von Willebrand's factor and mucins. Sequence similarities to heparin-binding motifs are also found within this domain.
Proteolysis of the secreted full-length CCN proteins that has been reported in the case of CCN2 and CCN3 might result in the production of CCN-derived peptides with high affinity for ligands that full-length CNN proteins bind only poorly. Amino-truncated CCN2 isoforms were biologically active whereas no specific biological activity has been attributed to the truncated CCN3. Although the molecular processes underlying the production of these secreted isoforms is presently unknown, it is important to note that proteolysis occur at the same amino acid residues in both CCN2 and CCN3. An elevated expression of CCN2 has also been detected by Northern blotting in human invasive mammary ductal carcinomas, dermatofibromas, pyogenic granuloma, endothelial cells of angiolipomas and angioleiomyomas, and in pancreatic tumors. A study performed with chondrosarcomas representative of various histological grades established that CCN2 expression was closely correlated with increasing levels of malignancy. In agreement with CCN2 playing a role in brain tumor angiogenesis, immunocytochemistry studies indicated that both glioblastoma tumor cells and proliferating endothelial cells stained positive for CCN2. In astrocytomas, CCN2 expression was particularly elevated in high grade tumors, with a marked effect of CCN2 on cell proliferation. Downregulation of CCN2 expression in these cells was associated with a growth arrest at the G1/S transition while over-expression of CCN2 induced a two-fold increase of the number of cells in the G1 phase. Gene profiling analysis allowed to identify a set of about 50 genes whose expression might account for the proliferative activity of CCN2 in these cells. CCN2 was seen in a higher proportion of mononuclear cells of patients with acute lymphoblastic leukemia.

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.

Atosiban is the first oxytocin antagonist to be specifically developed for the treatment of preterm labor. Atosiban has a specific mode of action, inhibiting oxytocin-induced uterine contractions by blocking oxytocin receptors in the uterus. Extensive clinical investigations have shown Atosiban to be at least as effective as current tocolytic agents. In addition, due to its novel and specific mode of action, Atosiban has a markedly improved maternal side effects profile compared with conventional therapies.