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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.

Tumor necrosis factor is a cytokine involved in systemic inflammation and is a member of a group of cytokines that all stimulate the acute phase reaction. TNF is mainly secreted by macrophages.
TNF causes apoptotic cell death, cellular proliferation, differentiation, inflammation, tumorigenesis and viral replication, TNF is also involved in lipid metabolism, and coagulation. TNF's primary role is in the regulation of immune cells.
Dysregulation and, in particular, overproduction of TNF have been implicated in a variety of human diseases- autoimmune diseases, insulin resistance, and cancer.

Galectin14, aka LGALS14, is a member of the galectin family of carbohydrate binding proteins. Galectin family members contain one or two carbohydrate recognition domains, which can bind beta-galactoside. The LGALS14 gene is predominantly expressed in the placenta. LGALS14 is expressed intracellularly in the placenta and eosinophils and is released by eosinophils following allergen stimulation. LGALS14 may be involved in the development of allergic inflammation.

Lymphotoxin Beta Receptor, also known as LTBR takes part in signaling during the development of lymphoid and other organs, lipid metabolism, immune response, and programmed cell death. In addition, the activity of this receptor has been associated to carcinogenesis. Alternatively spliced transcript variants encoding multiple isoforms have been observed for LTBR.

Troponin Complex is a heteromeric protein playing an important role in the regulation of skeletal and cardiac muscle contraction. It consists of three subunits, Troponin I , Troponin T and Troponin C. Each subunit is responsible for part of Troponin Complex function. E.g. Troponin I inhibits ATP-ase activity of acto-myosin. Troponin T and Troponin I are presented in cardiac muscles in different forms than in skeletal muscles. Purified subunits of rcTnI, rcTnC and rcTnT are recomplexed in vitro under appropriate conditions.

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.

MTHSFD, also known as Methenyltetrahydrofolate Synthetase Domain Containing protein, is linked to Pancreas, Annular and Gastrointestinal Defects. It has also been associated with Immunodeficiency Syndrome. Some of the Gene Ontology annotations that are related to the MTHSFD gene are nucleic acid binding and nucleotide binding.

Ephrin A5 (EFNA5) is a part of the ephrin ligand family which binds the members of ephrin receptor subfamily of tyrosine kinases and stimulates contact-dependent bidirectional signaling into neighboring cells. EFNA5 is mainly expressed in human adult brain, heart, spleen, and ovary and human fetal brain, lung, and kidney.

O-Sialoglycoprotein Endopeptidase, also known as OSGEP is a member of the KAE1 / TsaD family. OSGEP is essential for the formation of threonylcarbamoyl group on adenosine at position 37 (t6A37) in tRNAs which read codons beginning with adenine. OSGEP take a direct catalytic part in the above reaction, however other proteins of the complex are required to fulfill this activity.

Epiregulin is part of the EGF family. Epiregulin functions as a ligand of EGFR, as well as a ligand of most members of the ERBB (v-erb-b2 oncogene homolog) family of tyrosine-kinase receptors.Epiregulin is expressed mostly in the placenta and peripheral blood leukocytes and in specific carcinomas of the bladder, lung, kidney and colon. Epiregulin stimulates the proliferation of keratinocytes, hepatocytes, fibroblasts and vascular smooth muscle cells. Epiregulin inhibits the growth of several tumor-derived epithelial cell lines. Human Epiregulin is initially synthesized as a glycosylated 19.0 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a 6.0 kDa mature secreted sequence.

PDCD6IP is a Class E VPS protein which participates in concentration and sorting of cargo proteins of the multivesicular body or incorporation into intralumenal vesicles that are generated by invagination and scission from the limiting membrane of the endosome. PDCD6IP binds to the phospholipid lysobisphosphatidic acid which is abundant in MVBs internal membranes. The MVB pathway appears to require the sequential function of ESCRT-O, -I,-II and -III complexes. PDCD6IP is an adapter for a subset of ESCRT-III proteins, such as CHMP4, to function at distinct membranes. PDCD6IP is mandatory for completion of cytokinesis. PDCD6IP takes part in HIV-1 virus budding. PDCD6IP replaces TSG101 in its function of supporting HIV-1 release. PDCD6IP takes part in the regulation of both apoptosis and cell proliferation. PDCD6IP is a cytoplasmic protein that cooperates with apoptosis-associated proteins (ALG-2 and PDCD6) and with the endocytosis-regulator CIN85. Overexpression of PDCD6IP and endophilin

KLRC3 belongs to the NKG2 group that can be found mostly in natural killer (NK) cells and encodes a family of transmembrane proteins known for their C-type lectin domain and their type II membrane orientation (extracellular C terminus). The NKG2 gene family is situated inside the NK complex, a region which has quite a few C-type lectin genes mostly expressed on NK cells.

Polymerase (RNA) III (DNA directed) Polypeptide H(POLR3H) is a member of the eukaryotic RPB7/RPC8 RNA polymerase subunit family. POLR3H is DNA-dependent RNA polymerase which catalyzes the transcription of DNA into RNA utilizing the 4 ribonucleoside triphosphates as substrates. POLR3H has a central role in sensing and curbing infection by intracellular bacteria and DNA viruses. POLR3H functions as nuclear and cytosolic DNA sensor which is involved in innate immune response.

Cytokeratin 5 (KRT5) belongs to the keratin gene family. The type II cytokeratins are comprised of basic or neutral proteins which are arranged in pairs of heterotypic keratin chains coexpressed throughout differentiation of simple and stratified epithelial tissues. The type II cytokeratins are clustered in a region of chromosome 12q12-q13. The KRT5 type II cytokeratin is specifically expressed in the basal layer of the epidermis with family member KRT14. Mutations in these genes are linked with a complex of diseases termed epidermolysis bullosa simplex.

Tyrosylprotein Sulfotransferase 1, also known as TPST1 is the enzyme which catalyzes the sulfation reaction of protein tyrosines, a post-translational modification of proteins. TPST1 belongs to the protein sulfotransferase family. In addition, TPST1 utilizes 3'-Phosphoadenosine-5'-phosphosulfate (PAPS) as the sulfonate donor and also binds proteins with target tyrosineresidues to eventually form the tyrosine O-sulfate ester group in addition to the desulfonated 3’-phosphoadenosine-5’-phosphate.

CENPH is a member of the centromere protein H family. CENPH protein is a component of the CENPA-NAC (nucleosome-associated) complex which has a vital part in assembly of kinetochore proteins. The CENPA-NAC complex utilizes the CENPA-CAD (nucleosome distal) complex and is involved in integration of freshly synthesized CENPA into centromeres.

VAMP3 is present in recycling endosomes and endosome-derived vesicles. VAMP3 has been implicated in recycling of transferrin receptors to the plasma membrane, secretion of alpha-granules in platelets, recycling of T-cell receptors to the immunological synapses, and membrane trafficking during cell migration. VAMP-3 is present in human platelets and necessary for granule secretion. Synaptobrevins are the main components of a protein complex involved in the docking and/or fusion of synaptic vesicles with the presynaptic membrane. VAMP3 high homology to other VAMPs in its broad tissue distribution and subcellular localization is shown to be the human equivalent of the rodent cellubrevin. In platelets the protein resides on a compartment that is not mobilized to the plasma membrane on calcium or thrombin stimulation.

Mediator Complex Subunit 20 (MED20) is a subunit of the Mediator complex, which is a multiprotein coactivator of RNA transcription that interacts with DNA-bound transcriptional activators, RNA polymerase II, and general initiation factors. The Mediator functions as a link to transmit information from gene-specific regulatory proteins to the basal RNA polymerase II transcription apparatus. Mediator is recruited to promoters by direct interactions with regulatory proteins and functions as a scaffold for the compilation of a functional preinitiation complex with RNA polymerase II and the general transcription factors.

Family With Sequence Similarity 19 Member-A5 (FAM19A5) belongs to the TAFA family which is comprised of 5 highly homologous genes encoding small secreted proteins. These proteins have conserved cysteine residues at fixed positions, and are remotely related to MIP-1alpha, which is a member of the CC-chemokine family. The TAFA proteins are primarily expressed in specific regions of the brain, and are assumed to serve as brain-specific chemokines or neurokines which act as regulators of immune and nervous cells.

KRT18 encodes the type I intermediate filament chain keratin 18. Keratin 18, together with its filament partner keratin 8, are perhaps the most commonly found members of the intermediate filament gene family. They are expressed in single layer epithelial tissues of the body. Mutations in this gene have been linked to cryptogenic cirrhosis. Two transcript variants encoding the same protein have been found for this gene.

Chromogranin A is a 439 amino acid protein which is encoded on chromosome 14 and is present in neuroendocrine cells throughout the body, including the neuroendocrine cells of the large and small intestine, adrenal medulla and pancreatic islets. It is an excellent marker for carcinoid tumors, phenochromocytomas, paragangliomas, and other neuroendocrine tumors.
Coexpression of chromogranin A and neuron specific enolase (NSE) is common in neuroendocrine neoplasms.

Carbohydrate Sulfotransferase 10, also known as CHST10 is a member of the sulfotransferase 2 family. CHST10 was first recognized as a sulfotransferase which acts on the human natural killer-1 (HNK-1) glycan. Furthermore, CHST10 is a carbohydrate involved in neurodevelopment as well as synaptic plasticity.

Glycophorins A & B (GYPA &GYPB) are the main sialoglycoproteins of the human erythrocyte membrane which carry the antigenic determinants for the MN and Ss blood groups. Along with the M or N and S or s antigens which normally occur in all populations, approximately 40 related variant phenotypes were identified. These variants comprise all the variants of the Miltenberger complex and some isoforms of Sta, as well as Dantu, Sat, He, Mg, and deletion variants Ena, S-s-U- and Mk. GYPA is significant for the function of SLC4A1 and is necessary for high activity of SLC4A1. GYPA is involved in translocation of SLC4A1 to the plasma membrane. GYPA is also a receptor for: the influenza virus, Plasmodium falciparum erythrocyte-binding antigen 175 (EBA-175); binding of EBA-175 is dependent on sialic acid residues of the O-linked glycans and is also a receptor for Hepatitis A virus (HAV).