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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.

Omentin is a recently recognized gene highly localized to the mental tissue (visceral adipose tissue). Omentin is present in the stromal vascular cells in the adipose tissue rather than in the adipocytes. Omentin is predominantly expressed in the visceral adipose tissue than the subcutaneous tissue, with the omentin mRNA being 150 times higher in the visceral adipose tissue. Omentin has also been detected in human blood using western blot analysis, and seems to increase insulin-stimulated glucose uptake in 3T3-L1 adipocytes in mice. Omentin seems to increase Akt phosphorylation irrespective of insulin presence. Its role in glucose metabolism and obesity remains to be described; an insulin-sensitizing action is possible.Differences in Omentin expression has been noted in adipose tissue from normals and patients with inflammatory bowel disease although its significance is unknown.

Mannose-binding protein C (MBL2),belongs to the collectin family of patternrecognition molecules and is an important component in the innate immune system. MBL2 is a secreted glycoprotein which recognizes mannose and N-acetylglucosamine on various microorganisms, and is capable of activating the classical complement pathway. Lacking MBL2 has been associated with susceptibility to autoimmune and infectious diseases.

Lumican also known as LUM is a part of the small leucine-rich proteoglycan (SLRP) family which comprises decorin, biglycan, fibromodulin, keratocan, epiphycan, and osteoglycin. Furthermore, we can see that in these bifunctional molecules, the protein moiety binds collagen fibrils and the highly charged hydrophilic glycosaminoglycans regulate interfibrillar spacings. Lumican is the main keratan sulfate proteoglycan of the cornea however LUM is also distributed in interstitial collagenous matrices throughout the body. Lumican regulates collagen fibril organization and circumferential growth, corneal transparency, epithelial cell migration and tissue repair.

Leptin is a protein hormone. It is mainly produced in adipose cells that regulate energy homeostasis by restraining hunger. Leptin ties to nuclear receptors in the hypothalamus (arcuate nucleus). Similar to insulin resistance in type II diabetes, in obesity there is a decrease in the sensitivity towards leptin, ending in a failure to identify satiety, even in high levels of energy stores or leptin itself. Full-length cDNA encoding 2 leptin sequences (tLepA and tLepB) and 1 leptin receptor sequence (tLepR) exists in tilapia (Oreochromis niloticus). The full-length cDNA of tLepR is 3423 bp, encoding a protein of 1140 amino acid which contained all functionally important domains conserved among vertebrate leptin receptors. The cDNAs of tLepA and tLepB are 486 bp and 459 bp in length, encoding proteins of 161 aa and 152 aa, respectively. The three-dimensional structures of tLepA and tLepB demonstrates strong conservation of tertiary structure with that of human leptin comprised of 4 helixes.

Regulated upon Activation, Normal T-cell Expressed, and Secreted or RANTES is an 8 kDa protein classified as a chemotactic cytokine or chemokine. It has recently been renamed CCL5. RANTES is chemotactic for T cells, eosinophils and basophils and plays an active role in recruiting leukocytes into inflammatory sites. With the help of particular cytokines (i.e. IL-2 and IFN-?) that are released by T cells, RANTES also induces the proliferation and activation of certain natural killer (NK) cells to form CHAK (CC-Chemokine-activated killer) cells. It is also a HIV-suppressive factor released from CD8+ T cells. This chemokine has been localized to chromosome 17 in humans.

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.

Neurogranin (NRGN) is a calmodulin-binding protein which is expressed solely in the brain, mainly in dendritic spines. NRGN is also taking part in the protein kinase C signaling pathway by being a "third messenger" substrate of protein kinase C-mediated molecular cascades during synaptic development and remodeling. NRGN binds to calmodulin in the absence of calcium. NRGN protein’s phosphorylation by protein kinase C lowers its binding ability.

SRGN is identified as a hematopoietic cell granule proteoglycan. Proteoglycans stored in the secretory granules of various hematopoietic cells also hold a protease-resistant peptide core, and is vital for neutralizing hydrolytic enzymes. SRGN is related to the macromolecular complex of granzymes and perforin that acts as a intermediary of granule-mediated apoptosis.

Oncostatin M is a member of a cytokine family that includes leukemia-inhibitory factor, granulocyte colony-stimulating factor, and interleukin 6. This gene encodes a growth regulator which inhibits the proliferation of a number of tumor cell lines. It regulates cytokine production, including IL-6, G-CSF and GM-CSF from endothelial cells.

Follistatin is a single-chain gonadal protein that specifically inhibits follicle-stimulating hormone release. The single FST gene encodes two isoforms, FST317 and FST344 containing 317 and 344 amino acids respectively, resulting from alternative splicing of the precursor mRNA. In a study in which 37 candidate genes were tested for linkage and association with polycystic ovary syndrome (PCOS) or hyperandrogenemia in 150 families, evidence was found for linkage between PCOS and follistatin. Follistatin binds directly to activin and functions as an activin antagonist. specific inhibitor of the biosynthesis and secretion of pituitary follicle stimulating hormone (fsh).

Paraoxonase 2 (PON2) is a member of a multigene family whose genes share 65% identity at the amino acid level, and is expressed in a variety of tissues, including the pancreas. PON2 overexpression has been shown to lower the intracellular oxidative state and reduce the cells ability to oxidize LDL. PON2 is therefore implicated in the modulation of oxidative stress.

Legumain, also known as LGMN is a lysosomal cysteine protease which is found in all mouse tissues, however it was mainly abundant in the kidney as well as placenta. LGMN plays an essential role in the endosomal/lysosomal degradation system as the Legumain deficiency causes the accumulation of pro cathepsins B, H & L, another group of lysosomal cysteine proteases. Furthermore, over expression of LGMN in tumors is important for invasion/metastasis.

Maltose Binding Protein is a member of the maltose/maltodextrin system of E.Coli, which is accountable for the uptake and efficient catabolism of maltodextrins. The maltose/maltodextrin is a complex regulatory and transport system involving many proteins and protein complexes.
MBP elevates the yield of its fusion partner in many cases and is often able to promote the solubility of polypeptides to which it is fused.

RTN4IP1 is a unique mitochondrial protein that interacts with reticulon 4, which is an effective inhibitor of regeneration ensuing spinal cord injury. The reticulon 4 interaction with mitochondrial proteins may offer insight into the mechanisms for reticulon-induced inhibition of neurite growth.

The Melanoma Inhibitory protein (MIA) was identified as an inhibitor of in vitro growth of malignant melanoma cells. The protein contains a SH3 domain. MIA acts as a potent tumor cell growth inhibitor for malignant melanoma cells and some other neuroectodermal tumors, including gliomas, in an autocrine fashion. In a study of human melanoma cell lines with different metastatic capacity MIA mRNA expression appeared to be inversely correlated with pigmentation. MIA has been shown to represent a very sensitive and specific serum marker for systemic malignant melanoma that might be useful for staging of primary melanomas, detection of progression from localized to metastatic disease during follow-up, and monitoring therapy of advanced melanomas.

DCTN2 is a 50kDa subunit of dynactin, which is a macromolecular complex consisting of 10-11 subunits ranging in size from 22 to 150 kDa. Dynactin binds to both microtubules and cytoplasmic dynein. Dynactin is involved in a various cellular functions, including ER-to-Golgi transport, the centripetal movement of lysosomes and endosomes, spindle formation, chromosome movement, nuclear positioning, and axonogenesis. The DCTN2 subunit is present in 4-5 copies per dynactin molecule. DCTN2 is comprised of 3 short alpha-helical coiled-coil domains which mediate association with self or other dynactin subunits. DCTN2 interacts directly with the largest subunit (p150) of dynactin and is able to affix p150 in place. DCTN2 modulates cytoplasmic dynein binding to an organelle, and plays a part in prometaphase chromosome alignment and spindle organization during mitosis. DCTN2 is involved in anchoring microtubules to centrosomes. DCTN2 has a role in synapse formation during brain development.

Peroxisomal Biogenesis Factor 26 (PEX26) which is a part of the peroxin-26 gene family is probably required for protein import into peroxisomes. PEX26 attaches PEX1 and PEX6 to peroxisome membranes to form heteromeric AAA ATPase complexes needed for the import of proteins into peroxisomes. Deficiencies in this gene are the cause of peroxisome biogenesis disorder complementation group 8. PBD is a group of peroxisomal disorders evolving from a failure of protein import into the peroxisomal membrane or matrix.

Excess adiposity is the most important risk in the development of insulin resistance and type 2 diabetes mellitus (T2DM). Adipose tissue produces several proteins (adipocytokines) such as leptin, adiponectin, resistin, tumor necrosis factor-?, and IL-6, that modulate insulin sensitivity and appear to play an important role in the pathogenesis of insulin resistance, diabetes, dyslipidemia, inflammation, and atherosclerosis. However, the mechanisms by which fat tissue induces insulin resistance and the role of adipocytokines in the pathogenesis of T2DM have not been well established. Visfatin, also known as pre-B cell colony-enhancing factor (PBEF), is a cytokine that is highly expressed in visceral fat and was originally isolated as a secreted factor that synergizes with IL-7 and stem cell factors to promote the growth of B cell precursors. Visfatin homologs have been identified in carp, invertebrate mollusks, and bacteria, as well as in vertebrates, including humans and the mouse. It has been postulated to play a role in innate immunity.
Visfatin exerts insulin-mimetic effects that are dose-dependent and quantitatively similar to those of insulin in stimulating muscle and adipocyte glucose transport, and in inhibiting hepatocyte glucose production. Intravenous injection of recombinant visfatin in mice decreased plasma glucose in a dose-dependent fashion. In keeping with its insulin-mimetic effects, visfatin was as effective as insulin in reducing hyperglycemia in insulin-deficient diabetic mice. Visfatin was also found to be bound to and activate insulin receptor, causing receptor phosphorylation and the activation of downstream signaling molecules. However, visfatin and insulin did not compete for binding to the insulin receptor, indicating that the two proteins were recognized by different regions of the receptor. Thus, visfatin might play a role in glucose homeostasis and dysregulation in biosynthesis or signal transduction, and might contribute to the pathogenesis of diabetes.

RELM-beta (Resistin-Like Molecule-beta) is a member of a recently identified family of secreted proteins containing a conserved cystein-rich C-terminus. The RELM family consists of resistin (also called FIZZ3), RELM-alfa (FIZZ1), RELM-beta (FIZZ2) and RELM-gamma. Only resisistin and RELM-beta were found in humans whereas all four RELM family members were identified in rodents.
RELM-beta appears to be produced as a homodimer exclusively by intestinal goblet cells and can be found in high quantities in stool. Remarkably, stool of germ-free mice displaying sterile intestinal tract does not contain RELM-beta until bacterial colonization takes place after pathogen-free mice entered natural environment. Some, but not all, colon carcinoma cell lines secrete RELM-beta into the cell culture supernatant.
The physiological function of RELM-beta is not known. High doses of recombinant RELM-beta showed hyperglycemic effects including lowered glucose disposal and increased hepatic glucose production in mice.

A 16-kDa peptide hormone secreted from white adipocytes and implicated in the regulation of food intake and energy balance. Leptin provides the key afferent signal from fat cells in the feedback system that controls body fat stores.