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Polypeptide hormones secreted by the parathyroid glands, which promote release of calcium from bone to extracellular fluid by activating osteoblasts and inhibiting osteoclasts, indirectly promote increased intestinal absorption of calcium, and promote renal tubular reabsorption of calcium and increased renal excretion of phosphates. It is a major regulator of bone metabolism. Secretion of parathyroid hormone increases when the level of calcium in the extracellular fluid is low. Its action is opposed by calcitonin.
PTH (7-34), which is a PTH/PTHrP receptor antagonist, can stimulate hair growth and epidermal proliferation in mice.

Avidin is a tetrameric protein of 4 identical subunits (homotetramer) each of which can bind to biotin with a high degree of affinity and specificity. Avidin molecular weight in its tetrameric form is estimated to be between 66-69 kDa. Avidin is produced in the oviducts of birds, reptiles and amphibians and is subsequently deposited in the whites of their eggs. In the chicken egg white, avidin makes up roughly 0.05% of total protein (approximately 1.8 mg per egg). 10% of Avidin’s molecular weight is ascribed to carbohydrate content which is composed of four to five mannose and three N-acetylglucosamine residues. Avidin has at least three distinctive oligosaccharide structural type which are similar in structure and composition. The dissociation constant (KD) of avidin is approximately 10-15M, making it one of the strongest known non-covalent bonds.

Maltose Binding Protein is a member of the maltose/maltodextrin system of E.Coli, which is accountable for the uptake and efficient catabolism of maltodextrins. The maltose/maltodextrin is a complex regulatory and transport system involving many proteins and protein complexes. MBP elevates the yield of its fusion partner in many cases and is often able to promote the solubility of polypeptides to which it is fused.

Growth hormone receptor, also known as GHR is part of the cytokine receptor family. GHR binds 2 receptor molecules and in this manner induces signal transduction through receptor dimerization. Furthermore, at high concentrations, growth hormone performs as an antagonist since there is a large difference in affinities at the respective binding sites. The antagonist action can be enhanced further by reducing binding in the low affinity binding site.

LASP1 has a vital part in the regulation of dynamic actin-based, cytoskeletal activities. Agonist-dependent changes in LASP1 phosphorylation can additionally assist in regulation of actin-associated ion transport activities in the parietal cell and in several other F-actin-rich secretory epithelial cell types.

Transcription elongation factor A protein-like 8 (TCEAL8) is a member of the TFS-II family and TFA subfamily. TCEAL8 is involved in transcriptional regulation and localized in nucleus. TFS-II family members contain TFA domains and act as nuclear phosphoproteins which control transcription in a promoter context-dependent mode. Numerous family members are found on the X chromosome.

All three VEGF receptors belong to the class III subfamily of receptor tyrosine kinases (RTKs) characterised by the seven immunoglobulin-like loops in the extracellular domain. The expression of VEGFR-1 to -3 is almost exclusively restricted to hematopoietic precursor cells, vascular and lymphatic endothelial cells and to the monocyte/macrophage lineage. They play key roles in vasculogenesis, hematopoiesis, angiogenesis and lymphangiogenesis. The FLT-4 cDNA encodes a 1298 amino acid (aa) residue precursor protein with a 23 aa residue signal peptide. Mature VEGFR-3/FLT-4 is composed of a 751 aa residue extracellular domain, a 22 aa transmembrane domain and a 482 aa residue cytoplasmic domain. Both VEGF family members VEGF-C and VEGF-D have been shown to bind and activate VEGFR-3/FLT-4. The Flt-4 gene is widely expressed in the early embryo but becomes restricted to the lymphatic endothelial a latter stages of development. It is important for lymphangiogenesis.

Chromogranin A is a 439 amino acid protein which is encoded on chromosome 14 and is present in neuroendocrine cells throughout the body, including the neuroendocrine cells of the large and small intestine, adrenal medulla and pancreatic islets. It is an excellent marker for carcinoid tumors, phenochromocytomas, paragangliomas, and other neuroendocrine tumors.
Coexpression of chromogranin A and neuron specific enolase (NSE) is common in neuroendocrine neoplasms.

LRPAP1 is a member of the alpha-2-MRAP family. LRPAP1 cooperates with LRP1/alpha-2-macroglobulin receptor and glycoprotein 330. LRPAP1, located on the cell surface, creates a complex with the alpha 2 macroglobulin receptor light and heavy chains and has part in the pathogenesis of membrane glomerular nephritis.

COPZ1 is a member of the adaptor complexes small subunit family. Coatomer is an oligomeric complex which contains as a minimum the alpha, beta, beta', gamma, delta, epsilon and zeta subunits. The zeta subunit has a part in regulating the coat assembly and, therefore, the rate of biosynthetic protein transport due to its association-dissociation properties with the coatomer complex.

Pancreatitis-associated protein (PAP) is a secretory protein not normally expressed in healthy pancreas but highly induced during acute pancreatitis. While PAP has been shown to be anti-bacterial and antiapoptotic in vitro, its definitive biological function in vivo is not clear. Using antisepse oligonucleotides, inhibition of PAP expression significantly worsened pancreatitis in a rat model. During pancreatitis, PAP released by the pancreas could mediate lung inflammation through induction of hepatic TNF- alpha expression and subsequent increase in circulating TNF-alpha.
PAP is activated in primary liver cancers. In normal liver, the protein is undetectable in normal mature hepatocytes and found only in some ductular cells, representing potential hepatic progenitor cells. PAP can be considered hepatic cytokine that combines mitogenic and anti-apoptotic functions regarding hepatocytes, and consequently acts as a growth factor in vivo to enhance liver regeneration. In pancreatic cancor, PAP was overexpressed in 79% (30 of 38) of pancreatic ductal adenocarcinoma, 19% (7 of 36) of chronic pancreatitis, and 29% (2 of 7) of mucinous cystadenoma. PAP was found in malignant ductular structures in pancreatic carcinomas as well as in benign proliferating ductules and acinar cells in chronic pancreatitis. Elevation of PAP in patients with pancreatic cancer is not merely explainable by concomitant pancreatitis, but seems to be due to increased PAP production by the cancer cells and is also correlated to tumour load as expressed by the UICC stages.
Epithelial expression of PAP was induced under intestinal mucosal inflammation initiated by exposure to commensal bacteria or DSS as well as inflamed IBD colon. Increased serum level of PAP diagnosed ileal location in active Crohn disease with a sensitivity of 60%, a specificity of 94%, a positive predictive value of 84% and a negative predictive value of 81%. Elevated serum PAP (> 50 ng/mL) is significantly associated with disease activity and ileal location of Crohn disease.

Prealbumin is a thyroid hormone-binding protein that transports thyroxine from the bloodstream to the brain. Prealbumin is a carrier protein which transports thyroid hormones in the plasma and cerebrospinal fluid, and also transports retinol (vitamin A) in the plasma. Transthyretin consists of a tetramer of identical subunits and is dominantly produced in the liver. Mutations in Prealbumin are related to amyloid deposition, affecting predominantly peripheral nerve and/or the heart. The diseases caused by mutations include amyloidotic polyneuropathy, euthyroid hyperthyroxinaemia, amyloidotic vitreous opacities, cardiomyopathy, oculoleptomeningeal amyloidosis, meningocerebrovascular amyloidosis, and carpal tunnel syndrome. Prealbumin is an indicator of protein-energy malnutrition since it has a circulating half life of 2 days and reacts swiftly to changes in nutritional status.

GH is a member of the somatotropin/prolactin family of hormones which play an important role in growth control. The gene, along with four other related genes, is located at the growth hormone locus on chromosome 17 where they are interspersed in the same transcriptional orientation; an arrangement which is thought to have evolved by a series of gene duplications. The five genes share a remarkably high degree of sequence identity. Alternative splicing generates additional isoforms of each of the five growth hormones, leading to further diversity and potential for specialization. This particular family member is expressed in the pituitary but not in placental tissue as is the case for the other four genes in the growth hormone locus. Mutations in or deletions of the gene lead to growth hormone deficiency and short stature.

ZW10 Interacting Kinetochore Protein (ZWINT) is involved in kinetochore function. ZWINT is part of the MIS12 complex, which is essential for kinetochore formation and spindle checkpoint activity. ZWINT is localized to the cytoplasm during interphase and to kinetochores from late prophase to anaphase. ZWINT interacts with ZW10 (Zeste White 10) and regulates the association between ZW10 and kinetochores. ZWINT gene defects are linked with the pathogenesis of Roberts’s syndrome, an autosomal recessive disorder characterized by growth retardation due to premature chromosome separation.

Activins are homodimers or heterodimers of the different β subunit isoforms, part of the TGFβ family. Mature Activin A has two 116 amino acids residues βA subunits (βA-βA). Activin displays an extensive variety of biological activities, including mesoderm induction, neural cell differentiation, bone remodelling, haematopoiesis, and reproductive physiology. Activins takes part in the production and regulation of hormones such as FSH, LH, GnRH and ACTH. Cells that are identified to express Activin A include fibroblasts, endothelial cells, hepatocytes, vascular smooth muscle cells, macrophages, keratinocytes, osteoclasts, bone marrow monocytes, prostatic epithelium, neurons, chondrocytes, osteoblasts, Leydig cells, Sertoli cells, and ovarian granulosa cells.

Cystatin 7 (CST7) is a glycosylated cysteine protease inhibitor with a putative role in immune regulation through inhibition of a unique target in the hematopoietic system. Cystatin-7 is comprised of multiple cystatin-like sequences. The superfamily is comprised of 3 inhibitory families: the type 1 cystatins (stefins), type 2 cystatins and the kininogens. Some members are active cysteine protease inhibitors, while others have lost or possibly never had this inhibitory activity. Type 2 cystatin proteins are a class of cysteine proteinase inhibitors found in various human fluids and secretions. CST7 protein expression has been observed in numerous human cancer cell lines established from malignant tumors.

SCG5 also called 7B2 protein is localized in neuroendocrine tissues. SCG5 functions as a chaperone protein for the proprotein convertase PC2 and is essential for the production of an active PC2 enzyme.

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.

BRCA2 And CDKN1A Interacting Protein (BCCIP) is a nuclear protein with multiple interacting domains which remained conserved throughout the evolution. BCCIP is an important cofactor for BRCA2 in tumor suppression, and a modulator of CDK2 kinase activity via p21. BCCIP takes also part in the regulation of BRCA2 and RAD51 nuclear focus formation, doublestrand break-induced homologous recombination, and cell cycle progression.

OLR1 is a type II membrane protein which belongs to the C-type lectin family and performs as a cell-surface receptor for Ox-LDL. Ox-LDL has a part in early ather-osclerosis, which includes the transformation of monocyte-derived macro-phages to foam cells in atherosclerotic lesions. In addition, OLR1 protein triggers the activation of the NF?B signal transduction pathway.

EPGN is an EGF-related polypeptide growth factor that signals through the ErbB receptor-1. EPGN is produced in numerous tissues, including the testis, liver, heart and in certain tumor cells. EPGN is mitogenic for fibroblasts and epithelial cells. Human EPGN is originally synthesized as a glycosylated 14.7 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a mature soluble sequence.

EPGN is an EGF-related polypeptide growth factor that signals through the ErbB receptor-1. EPGN is produced in numerous tissues, including the testis, liver, heart and in certain tumor cells. EPGN is mitogenic for fibroblasts and epithelial cells. Human EPGN is originally synthesized as a glycosylated 14.7 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a mature soluble sequence.

The bone morphogenetic proteins (BMPs) are a family of secreted signaling molecules that can induce ectopic bone growth. Many BMPs are part of the transforming growth factor-beta (TGFB) superfamily. BMPs were originally identified by an ability of demineralized bone extract to induce endochondral osteogenesis in vivo in an extraskeletal site. Based on its expression early in embryogenesis, the BMP encoded by this gene has a proposed role in early development. In addition, the fact that this BMP is closely related to BMP5 and BMP7 has lead to speculation of possible bone inductive activity.