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Complement Factor B, also known as CFB, encodes complement factor B which is a component of the alternative pathway of complement activation. Factor B circulates in the blood as a single chain polypeptide. Once the alternative pathway is activated it is cleaved by complement factor D yielding the noncatalytic chain Ba and the catalytic subunit Bb. The active subunit Bb is a serine protease which connects with C3b to form the alternative pathway C3 convertase. Also, Bb is involved in the proliferation of preactivated B lymphocytes, while Ba inhibits their proliferation.

Cystatins are a superfamily of cysteine proteinase inhibitors found in both plants and animals. They comprise a group of proteinase inhibitors, widely distributed in tissues and body fluids, and form tight complexes with cysteine proteases such as cathepsin B, H, L and S. Cystatin C, a secreted molecule of this family, is of interest from biochemical, medicine and evolutionary points of view. Cystatin C, with molecular weight of 13260 Da, is composed of 120 amino acids, lacks carbohydrate and has two disulfide bridges located near the carboxyl terminus. Cystatin C is increased in patients with malignant diseases, and is related to the insufficiency of renal function and appears to be a better marker than creatinine. On the other hand, low levels of cystatin C involve cause the breakdown of the elastic laminae and, subsequently, the atherosclerosis and abdominal aortic aneurysm.

MED7 is a member of the Mediator complex subunit 7 family. The activation of gene transcription is a multistep course which is initiated by factors which identify transcriptional enhancer sites in DNA and collaborate with co-activators to direct transcriptional initiation by the RNA polymerase II apparatus. The gene encode a subunit of the CRSP (cofactor required for SP1 activation) complex, that, together with TFIID, is needed for effective activation by SP1. Additionally, MED7 is also an element of other multisubunit complexes e.g. thyroid hormone receptor-(TR-) associated proteins that cooperate with TR and enables TR function on DNA templates in conjunction with initiation factors and cofactors.

Cytohesin 3 (CYTH3) belongs to the PSCD family, whose members have identical structural organization which consists of an N-terminal coiled-coil motif, a central Sec7 domain, and a C-terminal pleckstrin homology (PH) domain, and seem to mediate the regulation of protein sorting and membrane trafficking. CYTH3 is involved in the regulation of Golgi structure and function, and it might have a physiological role in regulating ADP-ribosylation factor protein 6 (ARF) functions, in addition to acting on ARF1.

Leukocyte-associated immunoglobulin-like receptor 2 (LAIR2) is a secreted, 131 amino acids protein which contains one IglikeC2 type domain, rendering it a member of the Ig superfamily. Even though one is secreted and one is membrane bound, the 2 LAIR proteins are assumed to have evolved from a common gene ancestor and seem to share similar adhesion profiles, suggesting that LAIR2 may compete with LAIR1 for ligand binding. LAIR2 was discovered by its similarity to LAIR1, which is an inhibitory receptor present on mononuclear leukocytes. The LAIR2 gene maps to a region of 19q13.4, dubbed the leukocyte receptor cluster, which contains 29 genes in the immunoglobulin superfamily, including LAIR1. The function of the LAIR2 protein is unknown, though it is assumed to be secreted and may help modulate mucosal tolerance.

PTB domain-containing engulfment adapter protein 1 (GULP1) is an evolutionarily conserved adaptor protein essential for efficient phagocytosis of apoptotic cells by phagocytes. Furthermore, GULP1 helps modulate cellular glycosphingolipid and cholesterol transport. In addition, GULP1 may have a role in the internalization and endosomal trafficking of various LRP1 ligands, such as PSAP. Increased cytoplasmic levels of GULP1 are linked with increases in cellular levels of GTP-bound ARF6.

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.

Osteoprotegerin acts as decoy receptor for rankl and thereby neutralizes its function in osteoclastogenesis. OPG inhibits the activation of osteoclasts and promotes osteoclast apoptosis in vitro. Bone homeostasis seems to depend on the local rankl/opg ratio. Osteoprotegerin may also play a role in preventing arterial calcification. May act as decoy receptor for trail and protect against apoptosis. Trail binding blocks the inhibition of osteoclastogenesis.

EDA2R (ectodysplasin A2 receptor) mediates the activation of the NF-kappa-B and JNK pathways. Activation seems to be mediated through binding to TRAF3 and TRAF6. In addition, Mutations in EDA give rise to a clinical syndrome characterized by loss of hair, sweat glands, and teeth. EDA2R specifically binds to EDA-A2 isoform. This protein is a type III transmembrane protein of the TNFR (tumor necrosis factor receptor) superfamily, and contains 3 cysteine-rich repeats and a single transmembrane domain however it lacks an N-terminal signal peptide. Alternatively spliced transcript variants have been found for this gene. Among the diseases associated with EDA2R are ectodermal dysplasia 1, hypohidrotic, x-linked, and hypohidrotic ectodermal dysplasia.

CCNA2 is a member of the highly conserved cyclin family, whose members are characterized by a dramatic periodicity in protein abundance through the cell cycle. Cyclins act as regulators of CDK kinases. Various cyclins demonstrate distinct expression and degradation patterns which contribute to the temporal coordination of each mitotic event. Contrary to cyclin A1, which is present only in germ cells, CCNA2 is expressed in all tissues tested. CCNA2 binds and activates CDC2 or CDK2 kinases, and consequently promotes both cell cycle G1/S and G2/M transitions.

GDF15 is part of the TGF-Beta superfamily that is involved in regulating inflammatory and apoptotic pathways in injured tissues and throughout disease processes. GDF15 is most abundant in the liver. Its expression in liver can be considerably up-regulated in during injury of organs such as liver, kidney, heart and lung. GDF-15 promotes proliferation or growth arrest and differentiation due to differences in cellular differentiation. GDF15 prevents apoptosis in cerebellar granule neurons by activating Akt and inhibiting endogenously active ERK. GDF15 is a novel autocrine/endocrine factor that antagonizes the hypertrophic response and loss of ventricular performance.

SIL1 is localized to endoplasmic reticulum (ER). SIL1 is an N-linked glycoprotein with an N-terminal ER targeting sequence, 2 putative N-glycosylation sites, and a C-terminal ER retention signal. SIL1 acts as a nucleotide exchange factor for another unfolded protein response protein. Mutations in SIL1 are linked to Marinesco-Sjogren syndrome.

Ectodysplasin A Receptor, also known as EDAR belongs to the tumor necrosis factor receptor family. EDAR is a receptor for the soluble ligand ectodysplasin A, and is capable of activating the nuclear factor-kappaB, JNK, as well as caspase-independent cell death pathways. EDAR is necessary for the development of hair, teeth, and other ectodermal derivatives. Furthermore, mutations in EDAR resulted in autosomal dominant and recessive forms of hypohidrotic ectodermal dysplasia.

Chemokine (C-C motif) ligand 19 (CCL19) is a small cytokine belonging to the CC chemokine family that is also known as EBI1 ligand chemokine (ELC) and macrophage inflammatory protein-3-beta (MIP-3-beta). CCL19 is expressed abundantly in thymus and lymph nodes, with moderate levels in trachea and colon and low levels in stomach, small intestine, lung, kidney and spleen. The gene for CCL19 is located on human chromosome 9. This chemokine elicits its effects on its target cells by binding to the chemokine receptor chemokine receptor CCR7. It attracts certain cells of the immune system, including dendritic cells and antigen-engaged B cells.

BNIP1 belongs to the of the BCL2/adenovirus E1B 19 kd-interacting protein (BNIP) family. BNIP1 interacts with the E1B 19 kDa protein, which defends cells from virally-induced cell death. In addition, BNIP1 interacts with E1B 19 kDa-like sequences of BCL2 which is an additional apoptotic protector. Adding up, BNIP1 is implicated in vesicle transport into the endoplasmic reticulum. Alternative splicing results of BNIP1 in four protein products with identical N- and C-termini have been found.

ARL11 (ADP-ribosylation factor-like protein 11) belongs to the ARF family of the Ras superfamily of small GTPases which are known to be involved in multiple regulatory pathways altered in human carcinogenesis. ARFs are highly conserved guanine nucleotide binding proteins which enhance the ADP-ribosyltransferase activity of choleratoxin. ARFs are important in eukaryotic vesicular trafficking pathways and they have a vital role in the activation of phospholipase D (PC-PLD). ARL11 is assumed to act as a tumor suppressor which may have a role in the regulation of apoptosis.

Collapsin response mediator proteins (CRMPs) are cytosolic phosphoproteins involved in neuronal differentiation and axonal guidance. CRMP2 was previously shown to mediate the repulsive effect of Sema3A on axons and to participate in axonal specification. The X-ray crystal structure of murine CRMP1 was determined at 2.1 resolution and demonstrates that CRMP1 is a bilobed ‘lung-shaped’ protein forming a tetrameric assembly.

SIRT2 belongs to the sirtuin family of proteins, homologs to the yeast Sir2 protein. Proteins of the sirtuin family are characterized by a sirtuin core domain and grouped into four classes and take part in various processes, including transcriptional regulation, cell cycle progression, DNA-damage repair and aging. SIRT2 is a NAD-dependent deacetylase, which deacetylates the 'Lys-40' of alpha-tubulin.

CHMP2B is a member of the vacuolar sorting protein family. CHMP2B is a component of the ESCRT-III complex which is essential for sorting endosomal articles into multivesicular bodies (MVBs), and are also obligatory for the formation of these bodies. CHMP2B is usually found in brain, heart, skeletal muscle, small intestine, pancreas, lung, placenta and leukocytes.

Interleukin-8 (IL-8) is a chemokine produced by macrophages and other cell types such as epithelial cells. It is also synthesized by endothelial cells, which store IL-8 in their storage vesicles, the Weibel-Palade bodies. When first encountering an antigen, the primary cells to encounter it are the macrophages who phagocytose the particle. Upon processing, they release chemokines to signal other immune cells to come in to the site of inflammation. IL-8 is one such chemokine. It serves as a chemical signal that attracts neutrophils at the site of inflammation, and therefore is also known as Neutrophil Chemotactic Factor.

Cholera Toxin B subunit (ctxB) Cholera is a protein complex secreted by the bacterium Vibrio cholerae. ctxB is responsible for the massive, watery diarrhea characteristic of cholera infection. The cholera toxin is an oligomeric complex made up of 6 protein subunits: a single copy of the A subunit and5 copies of the B subunit, denoted as AB5. Subunit B binds while subunit A activates the G protein which activates adenylate cyclase. The five B subunits form a five-membered ring. The A subunit has 2 important segments. The A1 portion of the chain (CTA1) is a globular enzyme payload that ADP-ribosylates G proteins, while the A2 chain (CTA2) forms an extended alpha helix which sits snugly in the central pore of the B subunit ring.

SERF2 (small EDRK-rich factor 2) is a member of the SERF family. SERF2 is a protein-coding gene. Among the diseases associated with SERF2 are spinal muscular atrophy, and muscular atrophy.

Charged multivesicular body protein 6 (CHMP6) is a member of the SNF7 family. The CHMP6 protein is a core component of the endosomal sorting necessary for transport complex III (ESCRT-III) that is involved in multivesicular bodies (MVBs) formation and sorting of endosomal cargo proteins into MVBs. MVBs contain intraluminal vesicles (ILVs) which are produced by invagination and scission from the limiting membrane of the endosome and generally are transported to lysosomes facilitating degradation of membrane proteins, such as stimulated growth factor receptors, lysosomal enzymes and lipids.