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Membrane Metalloendopeptidase, also known as MME is a zinc metallopeptidase which is expressed at the cell surface of various cells. MME degrades the amyloid beta peptide whose abnormal misfolding as well as aggregation in neural tissue has been implicated as the cause for Alzheimer's disease. MME is expressed in an extended range of tissues and is especially plentiful in the kidney. MME is also a common acute lymphocytic leukemia antigen which is a significant cell surface marker in the diagnosis of human acute lymphocytic leukemia (ALL). MME is used in hematological diagnosis because it is expressed by early B, pro-B and pre-B lymphocytes, and also by lymph node germinal centers.

SFTPB is an amphipathic surfactant protein critical for lung function and homeostasis after birth. Pulmonary surfactant is a surface-active lipoprotein complex composed of 90% lipids and 10% proteins which consist of plasma proteins and apolipoproteins SPA, SPB, SPC and SPD. Pulmonary surfactant-associated proteins support alveolar stability by lowering the surface tension at the air-liquid interface in the peripheral air spaces. The SPB improves the rate of spreading and increases the stability of surfactant monolayers in vitro. SPB increases the collapse pressure of palmitic acid to approximately 70 millinewtons per meter.

R-spondin-3 (RSPO3) belongs to the thrombospondin type 1 repeat supergene family. RSPO3 is a secreted protein which is widely expressed in many tissues. RSPO3 contains 2 Furin-like repeats which have been found in various eukaryotic proteins involved in the mechanism of signal transduction by receptor tyrosine kinases, and one TSP type-1 domain. RSPO3 acts as an activator of the beta-catenin signaling cascade, initiating TCF-dependent gene activation.

CTNNBIP1 binds CTNNB1 and avoids interaction between CTNNB1 and TCF (T-cell transcription factor) family members. CTNNBIP1 is a negative regulator of the Wnt signaling pathway.

SAT-1 is a member the acetyltransferase family, and is a rate-limiting enzyme in the catabolic pathway of polyamine metabolism. SAT1 catalyzes the acetylation of spermidine and spermine, and is involved in the regulation of the intracellular concentration of polyamines and their transport out of cells. Therefore, SAT-1’s role is essential in polyamine homoeostasis, given that acetylated products are either excreted from the cell or oxidized by acetylpolyamine oxidase. Increased SAT1 activity causes variety of other effects which include pancreatic cells death, obstruction of regenerative tissue growth, behavioral changes, keratosis follicularis spinulosa decalvans (KFSD), and hair loss.
Defects in the SAT1 gene are linked to KFSD (keratosis follicularis spinulosa decalvans), which is a rare X-linked disorder affecting the skin and the eye. The KFSD affected men show thickening of the skin of the neck, ears, and extremities, particularly the palms and soles, loss of eyebrows, eyelashes and beard, thickening of the eyelids with blepharitis and ectropion, and corneal degeneration. Even though the majority of the affected families are compatible with an X-linked inheritance, KFSD are found to be clinically and genetically heterogeneous.

SMAD3 is part of the SMAD family of proteins that mediate signal transduction by the TGF-beta/activin/BMP-2/4 cytokine superfamily from receptor Ser/Thr protein kinases at the cell surface to the nucleus. SMAD3 has a role as a transcriptional modulator activated by TGF-Beta and is involved in the regulation of carcinogenesis. SMAD3 mutations are related with the pathogenesis of human osteoarthritis. SMAD3 expression take part in tumor suppression in the premature stages of gastric carcinogenesis. SMAD3 is involved in nuclear translocation of beta-catenin.

Serine/threonine-protein kinase 16 (STK16) is a membrane-associated protein kinase which phosphorylates on serine and threonine residues. STK16 is involved in secretory vesicle trafficking or intracellular signaling. Furthermore, the STK16 protein may have a role in regulating stromal-epithelial interactions which occur during ductal morphogenesis in the mammary gland. STK16 can autophosphorylate on Tyr residue; it is however unclear whether STK16 has tyrosine-protein kinase toward other proteins. STK16 may also be involved in TGF-beta signaling.

CCL25 (Teck) is a novel CC chemokine, which is distantly related (about 20% amino acid sequence identity) to other CC chemokines. The mouse CCL25 cDNA has also been cloned and shown to encode a 144 a.a. protein, which exhibits 49% a.a. sequence identity to the human CCL25. Human and mouse CCL25 expression was shown to be greatly restricted to the thymus and small intestine. While dendritic cells are identified as the source of CCL25 production in the thymus, dendritic cells derived from bone marrow do not express CCL25. CCL25 signals through the CCR9 receptor. Teck is possibly involved in T-cell development.
Recombinant human and mouse Teck were shown to be chemotactic for activated macrophages, dendritic cells and thymocytes. The recombinant protein demonstrates chemotactic activity on thymocytes, macrophages, THP-1 cells, and dendritic cells but is inactive on peripheral blood lymphocytes and neutrophils.

Caspase Recruitment Domain Family, Member 17 (CARD17) is a regulator of procaspase-1/CASP1 activation involved in the regulation of the proteolytic maturation of pro-IL-1beta/IL1B and its release throughout inflammation. CARD17 inhibits the release of IL1B in reaction to LPS in monocytes. Though, unlike CASP1, CARD17 do not induce NF-kappa-B activation.

VCPKMT is a member of the methyltransferase superfamily. VCPKMT is a protein-lysine N-methyltransferase which specifically trimethylates 'Lys-315' of VCP/p97; this alteration reduces VCP ATPase activity.

Numerous forms of Bartonellosis are caused by Bartonella henselae as well as Cat Scratch Disease & Bacillary Angiomatosis. It has been found that up to 95% of patients with Cat Scratch Disease show antibodies against Bartonella henselae antigens. Highly immunoreactive proteins which are produced by the Bartonella henselae are the most important antigens used for the diagnosis of Cat Scratch Disease. The immunogenic protein dihydrolipoamide-succinyltransferase also named SucB is an enzyme of the alpha-ketoglutarate dehydrogenase complex, which catalyzes the transport of a succinyl group from the S-succinyldihydrolipoyl moiety to coenzyme A.

Yersinia enterocolitica is a Gram-negative bacillus-shaped bacterium, which is a member of the Enterobacteriaceae family. Y.Enterocolitica is motile at temperatures between 22-29°C, however becomes non-motile at normal human body temperature. Y. Enterocolitica infection causes the yersiniosis disease, which is an animal-borne disease occurring in humans, as well as in a various groups of animals such as cattle, deer, pigs, and birds. Yersinia enterocolitica is a heterogeneous group of strains, which are conventionally classified by bio-typing into six bio-groups on the basis of phenotypic characteristics, and by serotyping into more than 57 “O” serogroups, on the basis of their O (lipopolysaccharide or LPS) surface antigen. Five of the six biogroups (1B and 2–5) are considered as pathogens. Nevertheless, only a few of these serogroups have been linked with disease in either humans or animals. Strains which belong to serogroups O:3 (biogroup 4), O:5,27 (biogroups 2 and 3), O:8 (biogroup 1B), and O:9 (biogroup 2) are most frequently isolated worldwide from human samples. Still, the main Y. enterocolitica serogroup in many European countries is serogroup O:3 followed by O:9, whereas the serogroup O:8 is mostly detected in the United States.

Adiponectin is a recently discovered 244 amino acid protein, the product of the apM1 gene, which is physiologically active and specifically and highly expressed in adipose cells (Adipokine). The protein belongs to the soluble defense collagen super family; it has a collagen-like domain structurally homologous with collagen VIII and X and complement factor C1q-like globular domain. APM-1 forms homotrimers, which are the building blocks for higher order complexes found circulating in serum.

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.

Syntaxin 4 (STX4) is a member of the syntaxin/epimorphin family of proteins. The Syntaxin family is cellular receptors for transport vesicles which participate in exocytosis in neutrophils. Syntaxin 4 is vital for normal regulation of glucose metabolism uptake in skeletal muscle and decline in STX4 protein levels lead to reduction of whole-body hormone-stimulated glucose metabolism. STX4 is expressed in neutrophils and neutrophil-differentiated HL-60 cells. The STX4 expression in neutrophils increases with differentiation.

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.

Synaptotagmin-11 (SYT11) protein may be involved in Ca2+-dependent exocytosis of secretory vesicles through Ca2+ and phospholipid binding to the C2 domain or may function as Ca2+ sensors in the process of vesicular trafficking and exocytosis.

CST6 belongs to the type 2 cystatin family. Unlike other family members that act as active cysteine protease inhibitors, CST6 restrain the inhibition of cathepsin B but is not active against cathepsin C. CST6 are secretable proteins that influence osteogenesis and bone resorption, regulation of the hepatocyte growth factor receptors, and the response to systemic inflammation.

Metallothionein 3 (MT3) contains 3 zinc and 3 copper atoms per polypeptide chain and a minor amount of cadmium. MT3 inhibits survival and neurite formation of cortical neurons in vitro. MT3 also binds heavy metals.

Kallistatin (SERPINA4) inhibits human amidolytic and kininogenase activities of tissue kallikrein. This inhibition is attained by formation of an equimolar, heat- and SDS-stable complex between the inhibitor and the enzyme, and production of a small C-terminal fragment of the inhibitor as a result of cleavage at the reactive site by tissue kallikrein.

Desmin is a muscle-specific class III intermediate filament. Homopolymers of this protein form a stable intracytoplasmic filamentous network connecting myofibrils to each other and to the plasma membrane. Mutations in this gene are associated with desmin-related myopathy, a familial cardiac and skeletal myopathy (CSM), and with distal myopathies.

APOM is belongs to the lipocalin protein family and is associated with high density lipoproteins and to a lesser extent with low density lipoproteins and triglyceride-rich lipoproteins. APOM is secreted through the plasma membrane but remains membrane-bound, where it takes part in lipid transport.