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Membrane cofactor protein isoform 14 (CD46), is a type I membrane protein which has cofactor activity for inactivation of complement components C3b and C4b by serum factor I. This function resides in the complement control protein repeats (CCPs), with CCP1–4 vital for regulation. CD46 is also involved in the fusion of the spermatozoa with the oocyte during fertilization. CD46 is common in thymocytes, T cells, B cells, monocytes, granulocytes, NK cells, platelets, endothelial cells, epithelial cells, fibroblasts, placenta and sperm.

Growth/differentiation factors (GDF1-GDF15) belong to the BMP family of TGF-beta superfamily proteins. These factors are produced as inactive preproproteins which are subsequently cleaved and assembled into active secreted homodimers. BMP13 is a growth factor which controls proliferation and cellular differentiation in the retina and bone formation. BMP13 has a central role in regulating apoptosis during retinal development. GDF proteins are vital during embryonic development, particularly in the skeletal, nervous, and muscular systems. BMP13 gene mutations result in colobomata, which are congenital abnormalities in ocular development, and in Klippel-Feil syndrome (KFS), which is a congenital disorder of spinal segmentation.

Chemokine (C-X-C motif) ligand 9 (CXCL9) is a small cytokine belongs to the CXC chemokine family that is also known as Monokine induced by gamma INF (MIG). CXCL9 is closely related to two other CXC chemokines called CXCL10 and CXCL11, whose genes are located near the gene for CXCL9 on human chromosome 4. CXCL9, CXCL10 and CXCL11 all elicit their chemotactic functions by interacting with the chemokine receptor CXCR3.

Neutrophil Cytosolic Factor 4 (NCF4) is a cytosolic regulatory factor of the superoxide-producing phagocyte NADPH-oxidase, which is a multicomponent enzyme system imperative for host defense. The NCF4 protein is preferentially expressed in cells of myeloid lineage. NCF4 interacts mainly with neutrophil cytosolic factor 2 (NCF2/p67-phox) to create a complex with neutrophil cytosolic factor (NCF1/p47-phox), which further interacts with the small G protein RAC1 and translocates to the membrane upon cell stimulation. This complex subsequently activates flavocytochrome b, the membrane-integratedcatalytic core of the enzyme system. The PX domain of the NCF4 protein can bind phospholipid products of the PI(3) kinase, suggesting its part in PI(3) kinase-mediated signaling events. The phosphorylation of the NCF4 protein negatively regulates the enzyme activity.

MHC Class II is consists of 2 membrane spanning proteins. Each of these proteins is roughly 30 kDa, and has of two Globular domains, Alpha-1, Alpha-2, Beta-1 and Beta-2. The two regions farthest away from the membrane are alpha-1 and beta-1. The two proteins link without Covalent Bonds. The MHC Class II protein mainly presents peptides, which have been digested from external sources. MHC Class II is normally only expressed by Antigen Presenting Cells (APC) which digest foreign protein. Within the RER the alpha and beta proteins of the molecule, associate with each other, while a third protein called the "invariant chain," is necessary for stabilizing the complex, without it, they will not associate. The MHC-invariant complex is then passed from the RER, into and out of, the Golgi body. It fuses with an Endocytic compartment, where an external protein has been sampled and degraded.

MHC Class II is consists of 2 membrane spanning proteins. Each of these proteins is roughly 30 kDa, and has of two Globular domains, Alpha-1, Alpha-2, Beta-1 and Beta-2. The two regions farthest away from the membrane are alpha-1 and beta-1. The two proteins link without Covalent Bonds. The MHC Class II protein mainly presents peptides, which have been digested from external sources. MHC Class II is normally only expressed by Antigen Presenting Cells (APC) which digest foreign protein. Within the RER the alpha and beta proteins of the molecule, associate with each other, while a third protein called the "invariant chain," is necessary for stabilizing the complex, without it, they will not associate. The MHC-invariant complex is then passed from the RER, into and out of, the Golgi body. It fuses with an Endocytic compartment, where an external protein has been sampled and degraded.

Uteroglobin (SCGB1A1) which belongs to the Secretoglobin (SCGBs) superfamily, is a multifunctional protein that exerts anti-inflammatory and anti-tumorigenic effects by binding small hydrophobic molecules such as phospholipids and prostaglandins. Uteroglobin is involved in numerous functions including anti-inflammation, inhibition of phospholipase A2 and the sequestering of hydrophobic ligands. SCGB1A1 is expressed by Clara cells, the non-ciliated, non-mucous secretory cells predominant in lung bronchioles, and by other epithelia which communicate with the external environment. On top of sequestering pro-inflammatory mediators and carcinogens, Uteroglobin is implicated in the inhibition of cell migration and invasion, platelet aggregation, and T cell differentiation. SCGB1A1 gene defects are associated with a susceptibility to asthma.

Resistin, a product of the RSTN gene, is a peptide hormone belonging to the class of cysteine-rich secreted proteins which is termed the RELM family, and is also described as ADSF (Adipose Tissue- Specific Secretory Factor) and FIZZ3 (Found in Inflammatory Zone). Human resistin contains 108 amino acids as a prepeptide, and its hydrofobic signal peptide is cleaved before its secretion. Resistin circulates in human blood as a dimeric protein consisting of two 92 amino acid polypeptides, which are disulfide-linked via Cys26.
Resistin may be an important link between obesity resistance. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity. They have also suggested that resistin is present at elevated levels in blood of obese mice, and is down regulated by fasting and antidiabetic drugs. Way et al., on the other hand, have found that resistin expression is severly suppressed in obesity and is stimulated by several antidiabetic drugs.
Other studies have shown that mouse resistin increases during the differentiation of adipocytes, but it also seems to inhibit adipogenesis. In contrast, the human adipogenic differentiation is likely to be associated with a down regulation of resistin gene expression.

ANXA6 is part of the family of calcium-dependent membrane and phospholipid binding proteins. ANXA6 mediats the endosome aggregation and vesicle fusion in secreting epithelia during exocytosis. ANXA6 correlates with CD21. ANXA6 regulates the release of Ca(2+) from intracellular stores. ANXA6 is differentially expressed in the lumbar spinal cord from rats submitted to peripheral lesion during neonatal period.

Chemokine (C-C motif) ligand 1 (CCL1) is a small glycoprotein secreted by activated T cells that belongs to a family inflammatory cytokines known as chemokines. CCL1 attracts monocytes, NK cells, and immature B cells and dendritic cells by interacting with a cell surface chemokine receptor called CCR8. This chemokine resides in a large cluster of CC chemokines on human chromosome 17.

Native human C8 is a glycosylated protein consist of 3 polypeptide chains: The alpha chain and the gamma chain are disulfide linkedwhereas, The beta chain is non-covalently bound to the a-g complex. C8 is necessary for formation of the membrane attack complex and is activated by binding on the cell membrane newly-formed C5b,C6,C7 complexes. Each pathway of complement activation generates proteolytic enzyme complexes which bind the target surface. These enzymes cleave a peptide bond in the larger alpha chain of C5 releasing C5a and activating C5b. Although C5b is unstable it remains bound to the activating complex for a few minutes during which it binds a single C6 from the surrounding fluid or it decays and is no longer capable of forming MAC.The C5b,6 complex may also remain connected to the C3/C5 convertase where the binding of a single C7 exposes a membrane-binding region and C5b,6,7 can enter into the bilipid layer of the target cell. Each C5b-7 complex can bind 1 molecule of C8 causing the complex to enter more firmly into the membrane.

CD86, also known as B7-2 or Cluster of Differentiation 86 is a protein necessary for T cell activation and survival, it is expressed on cells that are antigen-presenting cells and acts as costimulatory signals for T cells. CD86 is the ligand for CD28 (for autoregulation and intercellular association) and CTLA-4 (for attenuation of regulation and cellular disassociation), two different proteins.

ASB8 is a substrate-recognition component of a SCF-like ECS (Elongin-Cullin-SOCS-box protein) E3 ubiquitin-protein ligase complex that facilitates the ubiquitination and consequent proteasomal degradation of objective proteins.

The Defensin family are highly similar in their protein sequence and are microbicidal & cytotoxic peptides made by neutrophils. Beta Defensin-1 is an antimicrobial peptide having the resistance of epithelial surfaces to microbial colonization. Beta Defensin-1 has close proximity to Defensin Alpha-1 and has been implicated in the pathogenesis of cystic fibrosis.
Skin of patients having atopic dermatitis patients and mycosis fungoides (non-lesional and lesional) show lower human Beta Defensin-1 mRNA expression and higher human Beta Defensin-2 and human Beta Defensin-3 mRNA expression.
Beta Defensin is highly expressed by epithelial cells.
Beta-defensin 1 may play a role in the pathogenesis of severe sepsis.

ARG2 participates in the regulation of extra-urea cycle arginine metabolism and also in down-regulation of nitric oxide synthesis. Extrahepatic arginase functions to regulate L-arginine bioavailability to NO synthase. Since NO synthase is found in the penile corpus cavernosum smooth muscle, the clitoral corpus cavernosum and the vagina, ARG2 takes part in both male and female sexual arousal and therefore a potential target for the treatment of male and female sexual arousal disorders.

STAT1 is a member of the Signal Transducers and Activators of Transcriptionfamily of transcription factors. STAT1 is involved in upregulating genes due to a signal by either type Ior type IIinterferons. In response to IFN-?stimulation, STAT1 forms homodimers or heterodimers with STAT3that bind to the GAS (Interferon-Gamma Activated Sequence) promoter element; in response to either IFN-? or IFN-?stimulation, STAT1 forms a heterodimer with STAT2that can bind the ISRE (Interferon Stimulated Response Element) promoter element. In either case, binding of the promoter element leads to an increased expression of ISG (Interferon Stimulated Genes).

Cytidine deaminase (CDA) is an enzyme that scavenges exogenous and endogenous cytidine and 2'-deoxycytidine for UMP synthesis. CDA is one of several deaminases responsible for maintaining the cellular pyrimidine pool. CDA also catalyzes the deamination of chemotherapeutic cytosine nucleoside analogs such as Ara-C and 5-azacytidine, which results in the loss of their cytotoxic and antitumor function. CDA can form homotetramers and is generally expressed in granulocytes. Mutations in the CDA gene are linked to decreased sensitivity to the cytosine nucleoside analogue cytosine arabinoside used in the treatment of certain childhood leukemias.

Macrophage Inflammatory Proteins belong to the family of chemotactic cytokines known as chemokines. In humans, there are two major forms, MIP-1a and MIP-1b that are now also named CCL3 and CCL4. Both factors are produced by macrophages after they are stimulated with bacterial endotoxins. MIP-1a and MIP-1b activate human granulocytes (neutrophils, eosinophils and basophils) which can lead to acute neutrophilic inflammation. MIP-1a and MIP-1b induce synthesis and release of other pro-inflammatory cytokines such as interleukin-1 (IL-1), IL-6 and TNF-alpha from fibroblasts and macrophages. CCL3 and CCL4 genes are both located on human chromosome 17.

Annexin VII is a member of the annexin family of calcium-dependent phospholipid binding proteins. Annexin VII has molecular weight of approximately 51 kDa with a unique, highly hydrophobic N-terminal domain of 167 amino acids and a conserved C-terminal region of 299 amino acids. The latter domain is composed of alternating hydrophobic and hydrophilic segments. Structural analysis of the protein suggests that Annexin VII is a membrane binding protein with diverse properties including voltage-sensitive calcium channel activity, ion selectivity and membrane fusion.

ASB13 belongs to the ankyrin repeat and SOCS box-containing (ASB) family of proteins which contains ankyrin repeat sequence and a SOCS box domain. ASB13 is a protein coding gene that plays a role as a substrate-recognition part of a SCF-like ECS E3 ubiquitin-protein ligase complex which arbitrates the ubiquitination and subsequent proteasomal degradation of target proteins.

Fractalkine soluble form is chemotactic for t-cells and monocytes, but not for neutrophils. Fractalkine membrane-bound form promotes adhesion of those leukocytes to endothelial cells. Fractalkine regulates leukocyte adhesion and migration processes at the endothelium and binds to CX3CR1. Natural Human Fractalkine is produced as a long protein (373-amino acid) with an extended mucin-like stalk and a chemokine domain on top. The mucin-like stalk permits it to bind to the cell surface. Fractalkine gene is located on human chromosome 16 along with some CC chemokines known as CCL17 and CCL22.

SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor. The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

TNFAIP3-interacting protein 1 (TNIP1) interacts with zinc finger protein A20/TNFAIP3 and inhibits TNF-induced NF-kappa-B-dependent gene expression by interfering with a RIP- or TRAF2-mediated transactivation signal. Furthermore, TNIP1 interacts with HIV-1 matrix protein and is packaged into virions and its overexpression can inhibit viral replication. TNIP1 can regulate matrix nuclear localization, both nuclear import of Preintegration complex (PIC) and export of GAG polyprotein and viral genomic RNA during virion production.