Search results

Plasminogen activator inhibitor-1 is the principal inhibitor of tissue plasminogen activator(tPA) and uPA, the activators of plasminogenand hence fibrinolysis(the physiological breakdown of blood clots). It is a serine protease inhibitor(serpin) protein (SERPINE1). The other PAI, plasminogen activator inhibitor-2(PAI-2) is secreted by the placentaand only present in significant amounts during pregnancy. In addition, protease nexinacts as an inhibitor of tPA. SERPINE1, however, is the main inhibitor of the plasminogen activators.

Adhesion Molecule with Ig-Like Domain 2, also known as AMIGO2 is a member of the leucine-rich repeat family. AMIGO2 arbitrates homophilic in addition to heterophilic cell-cell interaction with AMIGO1 or AMIGO3. Furthermore, AMIGO2 contributes to signal transduction via its intracellular domain and is also essential for tumorigenesis of a subset of gastric adenocarcinomas.

P4HB is a multifunctional and highly abundant enzyme that is part of the protein disulfide isomerase family. When present as a tetramer consisting of two alpha and two beta subunits, P4HB has a role in hydroxylation of prolyl residues in preprocollagen. P4HB is a disulfide isomerase containing two thioredoxin domains that catalyze the formation, breakage and rearrangement of disulfide bonds.

PDCD1 is a cell surface membrane protein of the immunoglobulin superfamily. PDCD1 is expressed in pro-B-cells and is thought to have a role in their differentiation. In mice, expression of PDCD1 gene is induced in the thymus when anti-CD3 antibodies are injected and large numbers of thymocytes undergo apoptosis. Mice deficient for the PDCD1 gene bred on a BALB/c background developed dilated cardiomyopathy and died from congestive heart failure. These studies suggest that the PDCD1 gene product may also be important in T cell function and contribute to the prevention of autoimmune diseases.

TRIM21 is a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. The 52 kDa Ro protein is part of the RoSSA ribonucleoprotein, which includes a single polypeptide and one of four small RNA molecules. The RoSSA particle localizes to both the cytoplasm and the nucleus. Ro/SSA interacts with autoantigens in patients with Sjogren syndrome and systemic lupus erythematosus. Ribonucleoprotein particle is composed of a single polypeptide and one of four small RNA molecules. The RoSSA is present in all mammalian cells studied but has no known function. At least 2 isoforms are present in nucleated and red blood cells, and tissue specific differences in Ro/SSA proteins were identified.

Procalcitonin is a peptide hormone mainly produced by the C cells of the thyroid and certain endocrine cells of the lung. Under normal expression conditions, procalcitonin is immediately cleaved into three specific fragments, an N terminal residue, calcitonin and katacalcin. Levels of unprocessed procalcitonin rise significantly after bacterial infection, trauma or shock.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets. Its major physiologic role appears to be neutralization of molecules on the endothelial surface of blood vessels, thereby inhibiting local activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemocinfamily.

Phosphatidylinositol transfer protein beta isoform (PITPNB) is found in the cytoplasm, where it catalyzes the transfer of phosphatidylinositol (PI) and phosphatidylcholine (PC) between membranes. PITPNB mobilizes PI from the endoplasmic reticulum and regulates its release from stored vesicles in the Golgi network. PITPNB is extensively expressed in various tissues.

Immunoglobulin J chain (IGJ) helps to link 2 monomer units of either IgM or IgA and also also helps to bind these immunoglobulins to secretory component. When it comes to IgM, the J chain-joined dimer is a nucleating unit for the IgM pentamer and in the case of IgA it induces larger polymers.

Immunoglobulin G (IgG) are antibody molecules. Each IgG is composed of four peptide chains - 2 heavy chains g and 2 light chains. Also, each IgG has 2 antigen binding sites. IgG antibodies are involved in primarily the secondary immune response. The presence of specific IgG, generally, relates to maturation of the antibody response. IgG also has an imperative role in Antibody-dependent cell-mediated cytotoxicity (ADCC) and Intracellular antibody-mediated proteolysis, in which it binds to TRIM21 (the receptor with greatest affinity to IgG in humans) in order to direct marked virions to the proteasome in the cytosol.

Galectin-3 mediates with the alpha-3, beta-1 integrin the stimulation by cspg4 of endothelial cells migration. Galectin-3 plays an necessary part during the acquisition of vasculogenic mimicry and angiogenic properties associated with melanoma progression. LGALS3 overexpression is highly expressed in early stages of papillary carcinoma, and its expression intensity declines during tumor progression. Serum levels of LGALS3 are high in patients with thyroid malignancy but there is considerable overlap in serum LGALS3 concentrations between those with benign and malignant nodular thyroid disease. LGLAS3 takes part as an immune regulator to inhibit T-cell immune responses and promote tumor growth, as a result providing a new mechanism for tumor immune tolerance.

PSME1 is a Proteasome Activator 28 subunit alpha essential for presentation of certain major histocompatibility (MHC) class I antigens. The PSME1 complex is an alternate proteasome activator which operates with no use of ubiquitin. The PSME1 complex is made out of two homologous subunits, alpha and beta, that functions in similar catalytic properties and is connected to a hexameric ring.

Ribosomes are the organelles which catalyze protein synthesis and comprised of a small 40S subunit and a large 60S subunit. Combined, the small 40S and large 60S subunits are composed of 4 RNA types and about 80 structurally distinct proteins. RPS16, a ribosomal protein, is a component of the 40S subunit and a member of the S9P family of ribosomal proteins. RPS16 is situated in the cytoplasm. Just like other genes encoding ribosomal proteins, there are numerous processed pseudogenes of RPS16 spread through the genome.

AHSG (fetuin-A) which is a glycoprotein present in the serum, is synthesized by hepatocytes. AHSG is one of the fetuin class of plasma binding proteins. It is involved in a number of functions, such as endocytosis, brain development and the formation of bone tissue. It is usually present in the cortical plate of the immature cerebral cortex and bone marrow hemopoietic matrix, hence it has been postulated that it participates in the development of the tissues. Yet, its exact significance is still vague. AHSG promotes endocytosis, hold opsonic properties and influences the mineral phase of the bone. Affinity for calcium and barium ions has been shown.

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 I interferons.

Periostin is a disulfide linked 90 kDa, 811 amino acid protein originally isolated as a osteoblast-specific factor that functions as a cell adhesion molecule for preosteoblasts and is thought to be involved in osteoblast recruitment, attachment and spreading. Additionally, periostin expression has previously been shown to be significantly increased by both transforming growth factor beta-1(TGFbeta1) and bone morphogenetic protein (BMP-2). OSF-2 has a typical signal sequence, followed by a cysteine-rich domain, a fourfold repeated domain and a C-terminal domain. The fourfold repeated domain of OSF-2 shows homology with the insect protein fasciclin
Periostin mRNA is expressed in the developing mouse embryonic and fetal heart, and that it is localized to the endocardial cushions that ultimately divide the primitive heart tube into a four-chambered heart.

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.

Polymerase (RNA) II (DNA directed) Polypeptide K, also knownas POLR2K is am ember of the archaeal RpoP/eukaryotic RPC10 RNA polymerase subunit family. POLR2K is one of the smallest subunits of RNA polymerase II, the polymerase is responsible for synthesizing messenger RNA in eukaryotes. In addition, the other two DNA-directed RNA polymerases share this subunit.

TPRKB is a member of the CGI121/TPRKB family. TPRKB is localized to nucleus and cytoplasm and is ubiquitously expressed. TPRKB is known to cooperate with TP53RK/PRPK.

Chondrosarcoma Associated Gene 1 (CSAG1) belongs to a family of tumor antigens. The CSAG1 protein is expressed in chondrosarcomas, but may also be expressed in normal tissues such as testis.

Protein Kinase, AMP-Activated, Alpha 1 (PRKAA1) is a protein coding gene which is the catalytic subunit of AMPK. AMPK is an energy sensor protein kinase which regulates cellular energy metabolism. AMPK adjusts the activity of various important metabolic enzymes by direct phosphorylation. Among its other features, AMPK protects cells from stresses that cause ATP depletion by switching off ATP-consuming biosynthetic pathways.

TNFSF15 is a cytokine that belongs to the tumor necrosis factor (TNF) ligand family. This protein is abundantly expressed in endothelial cells, but is not expressed in either B or T cells. The expression of TNFSF15 is inducible by TNF and IL-1 alpha. This cytokine is a ligand for receptor TNFRSF25 and decoy receptor TNFRSF21/DR6. It can activate NF-kappaB and MAP kinases, and acts as an autocrine factor to induce apoptosis in endothelial cells. TNFSF15 is also found to inhibit endothelial cell proliferation, and thus may function as an angiogenesis inhibitor. An additional isoform encoded by an alternatively spliced transcript variant has been reported but the sequence of this transcript has not been determined.

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 modules: Module 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.

Procalcitonin is a peptide hormone mainly produced by the C cells of the thyroid and certain endocrine cells of the lung. Under normal expression conditions, procalcitonin is immediately cleaved into three specific fragments, an N terminal residue, calcitonin and katacalcin. Levels of unprocessed procalcitonin rise significantly after bacterial infection, trauma or shock.