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Resistin, also known as adipose tissue-specific secretory factor (ADSF) is a cysteine-rich peptide derived from adipose tissue. Resistin takes part in the inflammatory response, glucose metabolism, and angiogenesis.Resistin blocks insulinstimulated uptake of glucose by adipocytes and promote glucose release by hepatocytes. As such,Resistin considered to participate in diet‑induced insulin-sensitivity. Resistin causes high levels of lowdensity lipoprotein (LDL), increasing the risk of heart disease.

Resistin, a product of the RSTN gene, is a peptide hormone belonging to the class of cysteine-rich secreted proteins which is termed the RELM family, and is also described as ADSF (Adipose Tissue- Specific Secretory Factor) and FIZZ3 (Found in Inflammatory Zone). Human resistin contains 108 amino acids as a prepeptide, and its hydrofobic signal peptide is cleaved before its secretion. Resistin circulates in human blood as a dimeric protein consisting of two 92 amino acid polypeptides, which are disulfide-linked via Cys26.
Resistin may be an important link between obesity resistance. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity. They have also suggested that resistin is present at elevated levels in blood of obese mice, and is down regulated by fasting and antidiabetic drugs. Way et al., on the other hand, have found that resistin expression is severly suppressed in obesity and is stimulated by several antidiabetic drugs.
Other studies have shown that mouse resistin increases during the differentiation of adipocytes, but it also seems to inhibit adipogenesis. In contrast, the human adipogenic differentiation is likely to be associated with a down regulation of resistin gene expression.

Crystallins are the main structural proteins of the vertebrate eye lens, where they maintain the transparency and refractive index of the lens. Crystallins are divided into 3 fprotein families, α, β, & γ families. Because lens central fiber cells lose their nuclei during development, these crystallins are prepared and then retained throughout life, making them extremely stable proteins. CRYBB1 is a beta basic group member and undergoes extensive cleavage at its N-terminal extension during lens maturation.

This gene is a member of the EPO/TPO family and encodes a secreted, glycosylated cytokine composed of four alpha helical bundles. The protein is found in the plasma and regulates red cell production by promoting erythroid differentiation and initiating hemoglobin synthesis. This protein also has neuroprotective activity against a variety of potential brain injuries and antiapoptotic functions in several tissue types.

Adipogenesis Associated, Mth938 Domain Containing, also known as AAMDC is a member of the AAMDC family and takes part in preadipocyte differentiation andadipogenesis.

Chondrosarcoma Associated Gene 1 (CSAG1) belongs to a family of tumor antigens. The CSAG1 protein is expressed in chondrosarcomas, but may also be expressed in normal tissues such as testis.

Connective Tissue Growth Factor belongs to the CCN family of proteins. The CCN family presently consists of six members in human also known as: Cyr61 (Cystein rich 61), CTGF (Connective Tissue Growth Factor), Nov (Nephroblastoma Overexpressed gene), WISP-1, 2 and 3 (Wnt-1 Induced Secreted Proteins). The CCN genes encode secreted proteins associated with the Extracellular Matrix (ECM) and cell membrane.
CCN proteins are matricellular proteins which are involved in the regulation of various cellular functions including: proliferation, differentiation, survival, adhesion and migration. They are expressed in derivatives of the three embryonic sheets and are implicated in the development of kidney, nervous system, muscle, bone marrow, cartilage and bone. During adulthood, they are implicated in wound healing, bone fracture repair, and pathologies such as: fibrosis, vascular ailments and tumorigenesis.
Full length secreted CCN proteins can show an antiproliferative activity, whereas truncated isoforms are likely to stimulate proliferation and behave as oncogenes.
The full length protein consists of four modulesModule I shares partial identity with the N-terminal part of the IGFBPs.
Module II includes a stretch of 70amino acid residues – which shares sequence identity with the Von Willebrand Factor Type C repeat (VWC).
Module III contains sequences sharing identity with the Thrombospondin type 1 repeat (TSP1) (WSXCSXXCG), which is thought to be implicated in the binding of sulfated glycoconjugates and to be important for cell adhesion.
Module IV, also designated CT, is encoded by exon5. It is the leasts conserved one of the four domains at the level of nucleotide sequence, but it appears to be critical for several of the biological functions attributed to the CCN proteins. Module IV resembles the CT domain of several extracellular protein including, Von Willebrand's factor and mucins. Sequence similarities to binding motifs are also found within this domain.
Proteolysis of the secreted full-length CCN proteins that has been reported in the case of CCN2 and CCN3 might result in the production of CCN-derived peptides with high affinity for ligands that full-length CNN proteins bind only poorly. Amino-truncated CCN2 isoforms were biologically active whereas no specific biological activity has been attributed to the truncated CCN3. Although the molecular processes underlying the production of these secreted isoforms is presently unknown, it is important to note that proteolysis occur at the same amino acid residues in both CCN2 and CCN3. An elevated expression of CCN2 has also been detected by Northern blotting in human invasive mammary ductal carcinomas, dermatofibromas, pyogenic granuloma, endothelial cells of angiolipomas and angioleiomyomas, and in pancreatic tumors. A study performed with chondrosarcomas representative of various histological grades established that CCN2 expression was closely correlated with increasing levels of malignancy.
In agreement with CCN2 playing a role in brain tumor angiogenesis, immunocytochemistry studies indicated that both glioblastoma tumor cells and proliferating endothelial cells stained positive for CCN2. In astrocytomas, CCN2 expression was particularly elevated in high grade tumors, with a marked effect of CCN2 on cell proliferation. Downregulation of CCN2 expression in these cells was associated with a growth arrest at the G1/S transition while over-expression of CCN2 induced a two-fold increase of the number of cells in the G1 phase. Gene profiling analysis allowed to identify a set of about 50 genes whose expression might account for the proliferative activity of CCN2 in these cells.
CCN2 was seen in a higher proportion of mononuclear cells of patients with acute lymphoblastic leukemia.

Peptidyl-prolyl cis-trans isomerase F, mitochondrial (Cyclophilin-F) accelerates the folding of proteins. Cyclophilin-F catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and involved in regulation of the mitochondrial permeability transition pore (mPTP). Cyclophilin-F, in cooperation with mitochondrial TP53, is involved in activating oxidative stress-induced necrosis. Cyclophilin-F is also involved in modulation of mitochondrial membrane F1F0 ATP synthase activity and regulation of mitochondrial matrix adenine nucleotide levels. Furthermore, Cyclophilin-F has anti-apoptotic activity independently of mPTP and in cooperation with BCL2 inhibits cytochrome c-dependent apoptosis.

Homeodomain-only protein (HOPX) functions via its interaction with SRF, thus modulating the expression of SRF-dependent cardiac-specific genes and cardiac development. HOPX inhibits SRF-dependent transcription either by hindering SRF binding to DNA or by engaging histone deacetylase (HDAC) proteins which prevent transcription by SRF. HOPX is a homeodomain protein which lacks certain conserved residues required for DNA binding. HOPX overexpression causes cardiac hypertrophy.

NDRG1 is a cytoplasmic protein that is involved in stress responses, hormone responses, cell growth, and differentiation. NDRG1 is one of 4 members of the NDRG ?/?-hydrolase family. NDRG1 is classified in databases as a tumor suppressor and heavy metal-response protein. NDRG1’s functions include cell-cycle regulation, cellular differentiation, apoptosis, hypoxia response and metal-ion sensing. NDRG1 is also essential for p53-mediated caspase activation and apoptosis. The NDRG1 is a Rab4a effector that is involved in vesicular recycling of E-cadherin. NDRG1 is ubiquitous; it is expressed most notably in placental membranes and prostate, kidney, small intestine, and ovary tissues. NDRG1 has reduced expression in adenocarcinomas compared to normal tissues.
NDRG1 gene mutations are reported to be the cause for hereditary motor and sensory neuropathy-Lom (HMSNL), which is a severe autosomal recessive form of Charcot- Marie-Tooth (CMT) disease. In addition, decreased NDRG1 expression in glioma is linked to tumor progression. On the other hand, overexpression of NDRG1 is connected to malignant status of esophageal cancer. NDRG1 may also have a role in portal vein invasion and intrahepatic metastasis in human hepatocellular carcinoma.

Rho GDP-dissociation inhibitor 1 (ARHGDIA) is a member of the RAS gene superfamily, which encodes small guanine nucleotide exchange (GTP/GDP) factors. ARHGDIA, which is localized to the cytoplasm, inhibits the dissociation of GDP from Rho proteins, thus preventing GTP from binding to and consequently activating Rho proteins. In humans, the ARHGDIA can be phosphorylated at Ser 101 by p21-activated kinase, an event that inhibits its activity and may result in positive feedback regulation of several ARHGDIA target proteins.

SNAPIN is involved in the neurotransmitter release process through its modulation of the sequential interactions between the SNAREs and synaptotagmin. SNAPIN is part of the SNARE complex of proteins that is needed for synaptic vesicle docking and fusion. SNAPAP is enriched in neurons and exclusively located on synaptic vesicle membrane protein. SNAPIN is also an important factor of the BLOC1 multisubunit protein complex. BLOC1 is required for normal biogenesis of specialized organelles of the endosomal-lysosomal system, such as melanosomes and platelet dense granules.

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.

The secreted polypeptide noggin, encoded by the NOG gene, binds and inactivates members of the transforming growth factor-beta (TGF-beta) superfamily signaling proteins, such as bone morphogenetic protein-4 (BMP4). By diffusing through extracellular matrices more efficiently than members of the TGF-beta superfamily, noggin may have a principal role in creating morphogenic gradients. Noggin appears to have pleiotropic effect, both early in development as well as in later stages. It was originally isolated from Xenopus based on its ability to restore normal dorsal-ventral body axis in embryos that had been artificially ventralized by UV treatment. The results of the mouse knockout of noggin suggest that it is involved in numerous developmental processes, such as neural tube fusion and joint formation. Recently, several dominant human NOG mutations in unrelated families with proximal symphalangism (SYM1) and multiple synostoses syndrome (SYNS1) were identified; both SYM1 and SYNS1 have multiple joint fusion as their principal feature, and map to the same region (17q22) as NOG. All NOG mutations altered evolutionarily conserved amino acid residues. The amino acid sequence of human noggin is highly homologous to that of Xenopus, rat and mouse.

Chemokine (C-C motif) ligand 11 (CCL11) is a small cytokine belonging to the CC chemokine family that is also known as eotaxin. CCL11 selectively recruits eosinophils by inducing their chemotaxis, and therefore, is implicated in allergic responses. The effects of CCL11 are mediated by its binding to a G-protein-linked receptor known as a chemokine receptor. Chemokine receptors for which CCL11 is a ligand include CCR2, CCR3 and CCR5. The gene for human CCL11 (scya11) is encoded on three exons and is located on chromosome 17.

SULT1B1 enzyme in humans is encoded by the SULT1B1 gene. SULT1B1 holds a binding site for 3-prime-phosphoadenosine 5-prime-phosphosulfate, a sulfate donor, in addition to a cysteine residue conserved in the ST1 gene family of sulfotransferases. Sulfotransferases like SULT1B1 catalyze the biotransformation of a great amount of endogenous amalgams such as bile acids, neurotransmitters, steroids, and thyroid hormones, in addition to drugs and xenobiotics.

BPHL is a Serine hydrolase that is a part of the AB hydrolase superfamily which catalyzes the hydrolytic activation of amino acid ester prodrugs of nucleoside analogs. BPHL is expressed large quantities in liver and kidney and in minor quantities in heart, intestine and skeletal muscle. BPHL takes part in detoxification processes and is a specific alpha-amino acid ester hydrolase which favors small, hydrophobic, and aromatic side chains and does not have a strict necessity for the leaving group except for favoring a primary alcohol.

CXCL14 is involved in immunoregulatory and inflammatory processes. BRAK protein is structurally related to the CXC (Cys-X-Cys) subfamily of cytokines. CXCL14 displays chemotactic activity for monocytes but not for lymphocytes, dendritic cells, neutrophils or macrophages. CXCL14 is involved in the homeostasis of monocyte-derived macrophages.

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.

PFN4 is a small actin-binding protein that participates in the dynamic turnover and restructuring of the actin cytoskeleton. PFN4 is localized in all eukaryotic organisms in the majority of cells. PFN4 is crucial for spatially and temporally controlled growth of actin microfilaments, which is a necessary process in cellular locomotion and cell shape changes.

Filamin is a large (270kd) dimeric actin crosslinking protein from a variety of sources, which helps to stabilize the 3D cortical actin network. The fundamental structure of filamin is well conserved and consists of an actin binding domain at the N-terminus followed by a C-terminal rod domain consisting of numerous repeat segments ranging from 4 in C. elegans to 24 in mammalian cells. Each repeat in the rod domain consists of roughly 100 residues and forms an immunoglobulin like fold. Such immunoglobulin folds have been found in a variety of proteins and are responsible for protein-protein interactions. Filamin Human actin-binding protein (ABP), aka filamin, crosslinks actin filaments into orthogonal networks in cortical cytoplasm and participates in the anchoring of membrane proteins for the actin cytoskeleton. Mammalian filamin interacts directly with at least 30 proteins such as transmembrane receptors, second messenger-associated proteins, protein kinases, phosphatases and cytoskeletal proteins and these interactions have been shown to require one or more of the repeat elements in the rod domain.

Fractalkine soluble form is chemotactic for t-cells and monocytes, but not for neutrophils. Fractalkine membrane-bound form promotes adhesion of those leukocytes to endothelial cells. Fractalkine regulates leukocyte adhesion and migration processes at the endothelium and binds to CX3CR1. Natural Human Fractalkine is produced as a long protein (373-amino acid) with an extended mucin-like stalk and a chemokine domain on top. The mucin-like stalk permits it to bind to the cell surface. Fractalkine gene is located on human chromosome 16 along with some CC chemokines known as CCL17 and CCL22.

TMEFF1 is a type I transmembrane glycoprotein which includes 2 follistatin modules and an EGF domain in its extracellular domain, a transmembrane domain and a short cytoplasmic tail. The extracellular domain of TMEFF1 can be released as a soluble protein. TMEFF1 is primarily expressed in brain, but is downregulated in brain neoplasms. TMEFF1 selectively regulates nodal but not activin signaling through direct binding to the nodal co-receptor, Cripto. TMEFF inhibits NODAL and BMP signaling through neural patterning and also a possible tumor suppressor in brain cancers.

Ferritin is a fairly large, iron-storage heteropolymeric protein composed of 2 subunit types, light Ferritin & heavy Ferritin polypeptides, which is expressed in most kinds of cells and co-assemble in different proportion in a tissue-specific manner. Ferritin is composed of 24 self-assembled polypeptide subunits of the heavy and light ferritin chains and is characterized by the capacity to remove Fe (II) from solution in the presence of oxygen.
Ferritin light polypeptide protein is the main intracellular iron storage protein in prokaryotes and eukaryotes. Variation in ferritin subunit composition influence the rates of iron uptake and release in various tissues. A key function of ferritin is the storage of iron in a soluble and nontoxic state. Defects in this light chain ferritin gene are associated with several neurodegenerative diseases and hyper ferrit anemia-cataract syndrome.
Ferritin stores iron in a soluble, nontoxic, readily accessible form. Ferritin is needed for iron homeostasis. Iron is taken up in the ferrous form and deposited as ferric hydroxides after it has been oxidized.