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Semaphorin-4D (CD100) is a member of the semaphorin family containing 1 Ig-like C2-type domain, 1 PSI domain and 1 Sema domain. CD100 is the cell surface receptor forPLXN1B and PLXNB2 which plays a central role in cell-cell signaling. CD100 stimulates the migration of cerebellar granule cells and of endothelial cells, regulates dendrite and axon branching and morphogenesis. In addition, CD100 has a role in the immune system; it promotes signaling via SRC and PTK2B/PYK2, which subsequently mediates activation of phosphatidylinositol 3-kinase and of the AKT1 signaling cascade.

Heparanase is an endo β-D-glucuronidase, which degrades heparan sulfate side chains of heparan sulfate proteoglycans (HSPGs) in the extracellular matrix. Heparanase plays an important role in ECM degradation, facilitating the migration and extravasation of tumor cells and inflammatory leukocytes (1,2,3). Upon degradation, heparanase releases growth factors and cytokines that stimulate cell proliferation and chemotaxis (4,5). Heparanase is a heterodimer comprised of a 50 kDa subunit harboring the active site and a 8 kDa subunit. It is produced as a latent 65 kDa precursor and proteolytically processed to its active form (1,6). Heparanase is highly expressed in myeloid leukocytes (i.e. neutrophils) in platelets and in human placenta. Human heparanase was found to be upregulated in various types of primary tumors, correlating in some cases with increased tumor invasiveness and vascularity and with poor prospective survival (7,8).

Hepatoma-derived growth factor, related protein 3 (HDGFRP3/HDGF2) is the original member of a family of polypeptides labeled HDGF related proteins (HRPs). The HDGF2 protein augments DNA synthesis and may play a part in cell proliferation. HDGF2 is expressed primarily in the testis and the brain, to an intermediate extent in the heart, and to a slight extent in the ovaries, kidneys, spleen, and liver in humans.

Coagulation factor VIII participates in the intrinsic pathway of blood coagulation; factor VIII is a cofactor for factor IXa which, in the presence of Ca+2 and phospholipids, converts factor X to the activated form Xa. This gene produces two alternatively spliced transcripts. Transcript variant 1 encodes a large glycoprotein, isoform a, which circulates in plasma and associates with von Willebrand factor in a noncovalent complex. This protein undergoes multiple cleavage events. Transcript variant 2 encodes a putative small protein, isoform b, which consists primarily of the phospholipid binding domain of factor VIIIc. This binding domain is essential for coagulant activity. Defects in this gene results in hemophilia A, a common recessive X-linked coagulation disorder.

Serpin Peptidase Inhibitor, Clade A Member 8 (SERPINA8), which is a pre-angiotensinogen or angiotensinogen precursor, is expressed in the liver and cleaved by the enzyme renin in response to lowered blood pressure. The ensuing product, angiotensin I, is at that point cleaved by angiotensin converting enzyme (ACE) to produce the physiologically active enzyme angiotensin II. SERPINA8 protein is involved in maintaining blood pressure and in the pathogenesis of essential hypertension and preeclampsia. SERPINA8 gene mutations are linked with susceptibility to essential hypertension, and may cause renal tubular dysgenesis, which is a severe disorder of renal tubular development. Defects in the SERPINA8 gene are also linked with non-familial structural atrial fibrillation, and inflammatory bowel disease.

HP-NAP protects DNA from oxidative damage by sequestering intracellular Fe2+ ion and storing it in the form of Fe3+ oxyhydroxide mineral. One hydrogen peroxide oxidizes two Fe2+ ions, thus preventing hydroxyl radical production by the Fenton reaction. HP-NAP is necessary for the survival in the presence of oxidative stress. Dps is also a virulence factor which activates neutrophils, mast cells and monocytes. HP-NAP binds to neutrophil-glycosphingolipids and to sulfated carbohydrates on mucin. HP-NAP might play a part in the accumulation of neutrophils and monocytes at the site of infection. HP-NAP induces superoxide anion generation, adhesion and chemotaxis of neutrophils, via a pertussis toxin-sensitive pathway involving MAP kinases.

ANXA4 is part of the annexin family of calcium-dependent phospholipid binding proteins. ANXA4 has 45%-59% identity with other proteins of its family and shares a related size and exon-intron organization. ANXA4 interacts with ATP, and has in vitro anticoagulant activity and also inhibits phospholipase A2 activity. ANXA4 is exclusively expressed in epithelial cells. ANXA4 is a Calcium/phospholipid-binding protein which promotes membrane fusion and is involved in exocytosis.

GH 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, GH 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.

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.

Clusterin also named Apolipoprotein J (APO-J) is a 75-80 kD disulfide-linked heterodimeric protein containing about 30% of N-linked carbohydrate rich in sialic acid but truncated forms targeted to the nucleus have also been identified.
The precursor polypeptide chain is cleaved proteolytically to remove the 22-mer secretory signal peptide and subsequently between residues 227/228 to generate the a and b chains. These are assembled in anti-parallel to give a heterodimeric molecule in which the cysteine-rich centers are linked by five disulfide bridges and are flanked by two predicted coiled-coil a-helices and three predicted amphipathic a-helices.
Across a broad range of species clusterin shows a high degree of sequence homology ranging from 70% to 80%. It is nearly ubiquitously expressed in most mammalian tissues and can be found in plasma, milk, urine, cerebrospinal fluid and semen.
It is able to bind and form complexes with numerous partners such as immunoglobulins, lipids, heparin, bacteria, complement components, paraoxonase, beta amyloid, leptin and others. Clusterin has been ascribed a plethora of functions such as phagocyte recruitment, aggregation induction, complement attack prevention, apoptosis inhibition, membrane remodeling, lipid transport, hormone transport and/or scavenging, matrix metalloproteinase inhibition.
A genuine function of clusterin has not been defined. One tempting hypothesis says that clusterin is an extracellular chaperone protecting cells from stress induced insults caused by degraded and misfolded protein precipitates.
Clusterin is up- or down regulated on the mRNA or protein level in many pathological and clinically relevant situations including cancer, organ regeneration, infection, Alzheimer disease, retinitis pigmentosa, myocardial infarction, renal tubular damage, autoimmunity and others.

Vesicular overexpressed in cancer prosurvival protein 1 (VOPP1) has been previously shown to be over-expressed in human glioblastoma multiform and squamous cell carcinoma. VOPP1 is a crucial regulator of NF-kappaB signaling, and this high-level, amplification-mediated VOPP1 expression, such as that occurring in tumors with amplified EGFR, might impact the resistance to apoptosis.

HIV-1 and HIV-2 appear to package their RNA differently. HIV-1 binds to any appropriate RNA whereas HIV-2 preferentially binds to mRNA which creates the Gag protein itself. This means that HIV-1 is better able to mutate. HIV-2 is transmitted in the same ways as HIV-1: Through exposure to bodily fluids such as blood, semen, tears and vaginal fluids.
Immunodeficiency develops more slowly with HIV-2.
HIV-2 is less infectious in the early stages of the virus than with HIV-1.
The infectiousness of HIV-2 increases as the virus progresses.
Major differences include reduced pathogenicity of HIV-2 relative to HIV-1, enhanced immune control of HIV-2 infection and often some degree of CD4-independence. Despite considerable sequence and phenotypic differences between HIV-1 and 2 envelopes, structurally they are quite similar. Both membrane-anchored proteins eventually form the 6-helix bundles from the N-terminal and C-terminal regions of the ectodomain, which is common to many viral and cellular fusion proteins and which seems to drive fusion.
HIV-1 gp41 helical regions can form more stable 6-helix bundles than
HIV-2 gp41 helical regions however HIV-2 fusion occurs at a lower threshold temperature (25°C), does not require Ca2+ in the medium, is insensitive to treatment of target cells with cytochalasin B, and is not affected by target membrane glycosphingolipid composition.

Matrix metalloproteinases are a family of zinc and calcium-dependent endopeptidases that break down extracellular matrix proteins. The MMP9 is secreted as a 92kDa zymogen. Cleavage of ProMMP-9 results in the active enzyme, having a molecular weight of approximately 82kDa. MMP9 is composed of the following domains: a gelatin-binding domain consisting of three fibronectin type II units, a catalytic domain containing the zinc-binding site, a proline-rich type V collagen-homologous domain and a hemopexin-like domain. MMP9 is produced by the several cell types: monocytes, macrophages, neutrophils, keratinocytes, fibroblasts, osteoclasts and endothelial cells. MMP9 is involved in inflammatory responses, tissue remodeling, wound healing, tumor growth and metastasis. MMP9 may also play an important part in local proteolysis of the extracellular matrix and in leukocyte migration, as well as in bone osteoclastic resorption. MMP9 cleaves type IV and type V collagens into large C-terminal three quarter fragments and shorter N-terminal one quarter fragments. MMP9 can also degrade fibronectin but not laminin or Pz-peptide.
MMP9 defects may be a cause of susceptibility to intervertebral disc disease (IDD), also known as lumbar disk herniation (LDH).

Crystallin, Mu (CRYM) is a taxon-specific crystallin protein which binds NADPH and has sequence similarity to bacterial ornithine cyclodeaminases. CRYM doesn’t perform a structural role in lens tissue; instead CRYM binds thyroid hormone for possible regulatory or developmental roles. CRYM gene mutations are linked with autosomal dominant non-syndromic deafness. CRYM specifically catalyzes the reduction of imine bonds in brain substrates which may include cystathionine ketamine and lanthionine ketamine.

S100A8 is a part of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a broad range of cells, and participate in the regulation of cellular processes such as cell cycle progression and differentiation. S100A8 plays a role in the inhibition of casein kinase and as a cytokine. S100A8 altered expression is related with cystic fibrosis disease. S100A8 is a calcium-binding protein that has antimicrobial activity against bacteria and fungi.S100A8 is crucial for resistance towards invasion by pathogenic bacteria. S100A8 up-regulates transcription of genes that are under the control of NF-kappa-B. S100A8 plays a role in the development of endotoxic shock in response to bacterial lipopolysaccharide. S100A8 endorses tubulin polymerization and promotes phagocyte migration and infiltration of granulocytes at sites of wounding. S100A8 takes part as a pro-inflammatory mediator in acute and chronic inflammation and up-regulates the release of IL8 and cell-surface expression of ICAM1.

HES7 belongs to the Hairy and enhancer of split family of bHLH transcription factors. The mouse ortholog of the HES7 is set by Notch signaling. The protein serves as a transcriptional repressor, and is involved in correct patterning of the axial skeleton. A mutation in HES7 has been shown to result in spondylocostal dysostosis. Multiple transcript variants encoding different isoforms have been discovered for HES7.

Alpha 1 ACT is an early-stage acute-phase plasma protein and a serpin that preferentially inactivates chymotrypsin, cathepsin G, and chymase. Alpha-1-ACT, a serine protease inhibitor, is tightly associated with amyloid plaques in Alzheimer's disease (AD) and in normal aged human and monkey brain.
Regulation of the serine proteases and serine protease inhibitors plays an important role in neuromuscular differentiation. Prostate specific antigen (PSA), a chymotrypsin-like serine protease, is predominantly complexed to Alpha-1-ACT.

NK3 Homeobox1 (NKX3-1) is a homeobox-containing transcription factor, which binds preferentially the consensus sequence 5'-TAAGT[AG]-3' and may act as a transcriptional repressor. The NKX3-1 transcription factor functions as a negative regulator of epithelial cell growth in prostate tissue. NKX3-1 has an imperative role in normal prostate development, regulating proliferation of glandular epithelium and in the formation of ducts in prostate. In addition, NKX3-1 functions as a tumor suppressor controlling prostate carcinogenesis, as shown by its ability to inhibit proliferation and invasion activities of PC-3 prostate cancer cells. Abnormal expression of NKX3-1 is linked with prostate tumor progression.

Neurexophilin 1 (NXPH1) is a part of the neurexophilin family which encodes a secreted protein with a variable N terminal domain, an extremely conserved, N-glycosylated central domain, a short linker region, and a cysteine-rich Cterminal domain. NXPH1 shapes a very tight complex with alpha neurexins, a group of proteins which promote adhesion among dendrites and axons.

Eotaxin-3 (CCL26) is a small cytokine that belongs to the CC chemokine family also known as TARC (thymus and activation regulated chemokine). CCL26 is major eotaxin produced and released by alveolar epithelial cells which is involved in autoregulation of CCR3 receptors and other eotaxins. Eotaxin-3 is involved in immunoregulatory and inflammatory processes. Eotaxin-3 specifically binds and stimulates chemotaxis in T cells and elicits its effects by interacting with the chemokine receptor CCR4. CCL26 exhibits chemotactic activity for normal peripheral blood eosinophils and basophils. Eotaxin-3 may play a part in the eosinophil accumulation in atopic diseases. Eotaxin-3 is overexpressed in eosinophilic esophagitis, and the expression level correlates with disease severity. Eotaxin-3 is expressed constitutively in thymus, but only briefly in phytohemagglutinin-stimulated peripheral blood mononuclear cells. CCL26 is one of two Cys-Cys (CC) cytokine genes clustered on the q arm of chromosome 7.

STAM Binding Protein (STAMBP) is a zinc metalloprotease which specifically cleaves Lys-63-linked polyubiquitin chains, however it doesn’t cleave Lys-48-linked polyubiquitin chains. STAMBP has a role in signal transduction for cell growth and MYC induction mediated by IL-2 and GM-CSF. In addition, STAMBP potentiates BMP signaling by antagonizing the inhibitory action of SMAD6 and SMAD7. STAMBP also has a major role in regulation of cell surface receptor-mediated endocytosis and ubiquitin-dependent sorting of receptors to lysosomes. Endosomal localization of STAMBP is essential for efficient EGFR degradation but not for its internalization. STAMBP is also involved in the negative regulation of PI3K-AKT-mTOR and RAS-MAP signaling pathways.

PDCD6IP is a Class E VPS protein which participates in concentration and sorting of cargo proteins of the multivesicular body or incorporation into intralumenal vesicles that are generated by invagination and scission from the limiting membrane of the endosome. PDCD6IP binds to the phospholipid lysobisphosphatidic acid which is abundant in MVBs internal membranes. The MVB pathway appears to require the sequential function of ESCRT-O, -I,-II and -III complexes. PDCD6IP is an adapter for a subset of ESCRT-III proteins, such as CHMP4, to function at distinct membranes. PDCD6IP is mandatory for completion of cytokinesis. PDCD6IP takes part in HIV-1 virus budding. PDCD6IP replaces TSG101 in its function of supporting HIV-1 release. PDCD6IP takes part in the regulation of both apoptosis and cell proliferation. PDCD6IP is a cytoplasmic protein that cooperates with apoptosis-associated proteins (ALG-2 and PDCD6) and with the endocytosis-regulator CIN85. Overexpression of PDCD6IP and endophilin

CAPSL is a calcium-binding protein holding two conserved calcium-binding motifs (EF-hands) which are found in a superfamily of calcium sensors and calcium signal modulators. In addition, the CAPSL gene is in the same linkage disequilibrium (LD) block as the IL7R gene and there is well known association between the CAPSL-IL7R locus and type 1 diabetes.