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The cytokine Macrophage migration inhibitory factor (MIF) has been identified to be secreted by the pituitary gland and the monocyte/macrophage and to play an important role in endotoxic shock. MIF has the unique property of being released from macrophages and T cells in response to physiological concentrations of glucocorticoids. The secretion of MIF is tightly regulated and decreases at high, anti-inflammatory steroid concentration.

Osteoprotegerin, which is a member of the tumor necrosis factor receptor superfamily and is involved in the regulation of bone metabolism. OPGand its ligand (OPGL) are cytokines regulating osteoclasto-genesis. OPGL binds to receptors on the surface of preosteoclasts and stimulates their differentiation into active osteoclasts. This leads to osteoresorption. OPG inhibits this osteoclasto-genesis (OPG is secreted by osteoblasts, and binds to OPGL, thus inhibiting maturation of osteoclasts and osteoresorption). The degree and activity of osteoresorption depend mainly on the balance between OPG and its ligand (OPGL); factors increasing OPGL expression mostly reduce OPG expression and vice versa.

Maltose Binding Protein (MBP) is a part of the maltose/maltodextrin system of Eschericia coli bacteria, which is responsible for the uptake and efficient catabolism of maltodextrins. It is a complex regulatory and transport system involving many proteins and protein complexes.
Maltose binding protein MalE,MBP, is part of the maltodextrin transport system in E. coli. The maltodextrins diffuse through the LamB pore located in the outer membrane into the periplasm. The sugar is bound to MalE which prevents it to diffuse back outside. MalE passes the sugar to a complex of MalF and MalG in the cytoplasmic membrane where active tranport is mediated by the ATPase MalK. MBP molecular weight is 40,622 dalton. There are two domains in the protein with similar secondary structure (central pleated sheets are surrounded by helices) . The domains are connected by three bridges, between the domains is a deep groove in which the sugar is bound. All hydroxyl groups of the sugar are fixed by sidechains of the protein by hydrogen bonds. Some water molecules are part of the hydrogen bridge network.

MTPN is an ankyrin repeat protein, that stimulates protein synthesis and cardiomyocyte growth to commence cardiac hypertrophy by activating the NF-kappaB signaling cascade. Myotrophin participates in cerebellar morphogenesis and takes part in differentiation of cerebellar neurons, particularly of granule cells. High levels of MTPN are expressed in human dilated cardiomyopathic and ischemic hearts.

MAEA is a 396aa widely expressed adhesion protein which has 5 alternatively spliced isoforms. MAEA holds one CTLH domain and one LisH domain. MAEA forms a complex with F-actin, which takes part in regulating actin distribution in erythroblasts and macrophages and is known to assist in cell division and nuclear architecture. MAEA is confined with condensed chromatin at prophase, nuclear spindle poles at metaphase and in the contractile ring throughout cytokinesis phase and telophase.

Lassa virus, which is a member of the Arenaviridae virus family, causes acute viral hemorrhagic fever. It was first reported in 1969 in the town of Lassa, in Borno State, Nigeria. Natal multimammate mouse is the primary reservoir of Lassa virus, found in sub-Saharan Africa. The virus is transmitted by contact with the feces or urine of animals, contributing to its high rate of incidence. Lassa fever occurs generally in West Africa. Lassa fever results in 300,000 to 500,000 cases annually and causes about 5,000 deaths each year. Outbreaks of this disease have been observed in Nigeria, Liberia, Sierra Leone, Guinea, and the Central African Republic. Protein structure: Lassa virus genome is comprised of two single-stranded RNA molecules defined as small (S) and large (L). Two genes on the S segment encode the nucleoprotein (NP) and two envelope glycoproteins (GP1 and GP2); while, the L segment encodes the viral polymerase (L protein) and RING finger Z matrix protein. GP1 subunit serves a putative role in receptor binding, while the structure of GP2 subunit is consistent with viral transmembrane fusion proteins. NP is a virion protein which binds and protects the viral RNA.

Midkine (MK) is the product of a retinoic acid responsive gene. It contains 121 amino acid residues including 10 conserved cysteine residues, all of which appear to be disulphide linked.
Midkine is expressed during embryogenesis, showing an expression pattern that suggests functions in neurogenesis, cell migration, secondary organogenetic induction, and mesoderm-epithelial interaction.
The widespread downregulation of MK in the adult human is reverted in a number of cancers, in which polypeptides are able to act as both transforming growth factors and promoters of angiogenesis.
Midkine (MK), induces chemotaxis of human neutrophils and was found to trigger mobilization of intracellular calcium of these cells.
Midkine induces histamine release from rat peritoneal mast cells with a rapid response in a dose dependent manner.
Midkine is also a potent stimulator of collagen and glycosaminoglycan synthesis.

Myeloid leukemia factor 1 (MLF1) is a member of the MLF family, and is a widely expressed negative regulator of cell cycle progression functioning upstream of the tumor suppressor p53. MLF1 hinders the erythropoietin-induced erythroid terminal differentiation by averting cells from exiting the cell cycle through suppression of CDKN1B/p27Kip1 levels. MLF1 generally functions in multi-potent progenitor cells, and its dysregulation may be to some extent responsible for leukemogenesis. Translocations between the MLF1 gene and nucleophosmin are linked to myelodysplastic syndrome and acute myeloid leukemia.

Melanoregulin (MREG) takes part in membrane fusion and in regulating the biogenesis of disk membranes of photoreceptor rods. MREG is expressed in photoreceptor cells as two isoforms as a result of alternative splicing. MREG interacts with Peripherin-2, a photoreceptor specific tetraspanin protein which is required to preserve normal cell structure during the renewal process of membrane fusion. Moreover, MREG plays a part in the incorporation of pigments into hair.

Zinc-alpha-2-glycoprotein (ZAG) is found in body fluids such as serum, sweat, and seminal and breast cyst fluids. It is identical in amino acid sequence to tumor-derived lipid mobilizing factor (LMF), a protein associated with the dramatic loss of adipose body stores in cancer cachexia, and has been shown to stimulate lipolysis by adipocytes in vivo and in vitro. A role for ZAG has been proposed in the regulation of body weight, and age-dependent changes in genetically influenced obesity, and also it regulates melanin production by normal and malignant melanocytes. It has also recently been classified as a novel adipokine in that it is produced by both white and brown fat adipocytes and may act in a local autocrine fashion in the reduction of adiposity in cachexia. Controlling ZAG/LMF's activity could be life-saving in the management of certain cancers and other cachexiainducing conditions, and its possible normal role in body fat store homeostasis is deserving of understanding in its own right. ZAG exhibits a class I major histocompatibility complex (MHC) fold but is a soluble protein rather than being anchored to plasma membranes and does not associate with alpha-2-microglobulin in humans. Like antigen-presenting MHC class I proteins, ZAG has an open apical groove, and X-ray crystallography of human derived ZAG revealed an unidentifiable electron density in a similar position to that occupied by antigenic peptides in classical MHC proteins and glycolipids in isoforms of CD1. This presumptive ligand is not a peptide, and the groove is too small to hold a glycolipid such as is presented by CD1 isoforms. By analogy with all other MHC class I-related proteins that have an open apical groove [some do not ], occupancy by a ligand is probably crucial to ZAG's biological function. Despite all of the structural and biochemical evidence that ZAG binds a ligand, none has so far been found by extraction from protein isolated from biological fluids. This difficulty could be because the ligand is labile, heterogeneous, or readily lost during purification procedures. Knowing more about how ZAG interacts with the compounds it has been found to bind, both natural and artificial, will inform searches for the elusive ligand(s) and its/their role in ZAG's signaling function.

Mitochondrial antiviral signaling protein (MAVS) is vital for innate immune defense against viruses. MAVS is an intermediary protein essential in the virus-triggered IFN-beta signaling pathways. MAVS is involved in activation of transcription factors that regulate expression of IFN-beta and contributes to antiviral immunity.

MMADHC is a mitochondrial protein which takes part in an early step of vitamin B1 2 metabolism. Vitamin B12 (cobalamin) is vital for regular development and existence in humans. Mutations in MMADHC can result in methylmalonic aciduria and homocystinuria type cblD, a cobalamin metabolism syndrome which is characterized by decreased levels of the coenzymes methylcobalamin and adenosylcobalamin.

Oncomodulin is a member of the superfamily of calmodulin proteins, otherwise known as the EF-hand proteins. It is a high-affinity calcium ion-binding protein. Oncomodulin is an oncodevelopmental protein which is found in early embryonic cells in the placenta and also in tumors.

Kell blood group glycoprotein homolog or KEL, is an enzyme, part of the zinc endopeptidase of the neprilysin (NEP) group of proteins. KEL has a crucial part in the production of the potent bioactive ET-3, which also includes enzymes that are endothelin convertingenzymes (PEX, XCE, DINE &various NEP-like proteins). KEL uses a single disulfide bond to XK, a gated membranal transporter. The Kell antigen system that includes two proteins, is very crucial among blood group systems.

GMFB is part of the GMF subfamily of the larger actin-binding protein ADF family. GMFB is phosphorylated after phorbol ester stimulation, and is crucial for the nervous system. GMFB causes brain cell differentiation, stimulates neural regeneration and inhibits tumor cell proliferation. GMFB overexpression in astrocytes results in the increase of BDNF production. GMFB expression is increased by exercise, thus BDNF is important for exercise-induction of BDNF.

GFP is an intermediate filament. GFP and vimentin are linked to the same filament network; they are localized in the same filaments.
mRNAs encoding the glial intermediate filament protein are spatially dispersed in the glial cell cytoplasm close to the location of the glial filaments.

GLIPR2 is linked to plant pathogenesis-related (PR-1) proteins, which are upregulated in reaction to pathogen attack. GLIPR2 is localized within lipid-enriched microdomains on the cytosolic side of the endomembrane system. GLIPR2 is closely attached to membranes and lacks the cytosol, though it lacks a membrane-spanning domain.

Gametocyte Specific Factor 1 (GTSF1) is a member of the UPF0224 (FAM112) family and contains 1 CHHC-type zinc finger. A key paralog of the GTSF1 gene is GTSF1L.

sRAGE is a member of the immunoglobulin superfamily of cell surface molecules. sRAGE is a receptor for various molecules, including the amyloidogenic form of serum amyloid A, amyloid-beta protein, members of the S100/calgranulin superfamily and advanced glycation end products. sRAGE lies within the major histocompatibility complex (MHC) class III region on chromosome 6. Alternative splicing results in two transcript variants encoding different isoforms. sRAGE mediates interactions of nonenzymatic glycosylated proteins which accumulate in vascular tissue during aging & at an increasing rate in diabetes. sRAGE is a receptor for amyloid beta peptide.

MAGE belongs to the MAGE gene family, that comprises 12 known genes, of which 6 are expressed in tumors. The Melanoma-associated antigen 3 genes were originally isolated from different kinds of tumors, and based on their virtually limited tumor-specific expression in adult tissues, they were used as targets for cancer immunotherapy. MAGEA3 is a tumor-specific antigen extensively expressed in solid and hematologic malignancies, but not in normal tissues, with the exclusion of testis and placenta. Consequently, MAGEA3 is an outstanding candidate tumor antigen.

Sarcoglycan Beta, also known as SGCB, is a part of the sarcoglycan family. SGCB belongs to the sarcoglycan complex which is a subcomplex of the dystrophin-glycoprotein complex that connects between the F-actin cytoskeleton and the extracellular matrix.

Melanoma Antigen Family B,10 also known as MAGEB10 is a member of the B subfamily of the melanoma associated antigen protein family. MAGEB10 is specifically expressed in testis and tumor cells. One of the diseases associated with MAGEB10 is melanoma.

MAGEA6 belongs to the MAGEA family, which directs the expression of tumor antigens which are seen on a human melanoma by autologous cytolytic T lymphocytes (CTL). Members of the MAGEA family encode proteins with 50 to 80% sequence identity to each other. The MAGE genes, which are clustered at chromosomal location Xq28, were originally isolated from separate kinds of tumors, and based on their practically exclusive tumor-specific expression in adult tissues; they are objects for cancer immunotherapy. MAGEA genes’ promoters and first exons exhibit substantial variability, implying that the existence of the MAGEA gene family enables the same function to be expressed under different transcriptional controls. MAGEA genes are implicated in several hereditary disorders, such as dyskeratosis congenita.

Integrins are heterodimeric proteins consist of alpha and beta subunits. There are more than 18 alpha and 8 beta subunits discovered in mammals. Integrin family members are membrane receptors that participates in cell adhesion and recognition in a variety of processes including embryogenesis, hemostasis, tissue repair, immune response and metastatic diffusion of tumor cells. ITGB1 encodes a beta subunit.