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Adiponectin, also referred to as Acrp30, AdipoQ and GBP-28, 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.

Macrophage Inflammatory Proteins (MIP) belong to the family of chemotactic cytokines known as chemokines. In humans, there are two major forms, MIP-1a and MIP-1b that are now officially named CCL3 and CCL4 respectively. Both are major factors produced by macrophages after they are stimulated with bacterial endotoxins. They activate human granulocytes (neutrophils, eosinophilsand basophils) which can lead to acute neutrophilic inflammation. They also induce the synthesis and release of other pro-inflammatory cytokines such as interleukin 1 (IL-1), IL-6 and TNF-a from fibroblasts and macrophages. The genes for CCL3 and CCL4 are both located on human chromosome 17.

Neural Cell Adhesion Molecule 1 (NCAM1) is apart of the immunoglobulin superfamily. NCAM1 bindsspecifically to neurite fasciculation, neuronneuron adhesion, outgrowth of neurites, and more. The polysialyation of NCAM1 reduces its adhesive property and increases its neurite outgrowth promoting features.NCAM1is mainly expressed in NK cells and a subset of T lymphocytes that mediate MHC-unrestricted cellmediated cytotoxicity. High expression of NCAM-1 differentiates NK cells as having an activated phenotype. During hematopoiesis, NCAM1plays a role as the prototypic marker of NK cells and also present on subset of CD4+, CD8+ and T cells. In cell adhesion, NCAM1 contributes to cell-cell adhesion during embryonic development.

DnaK, originally identified for its DNA replication by bacteriophage l in E. coli is the bacterial HSP-70 chaperone. This protein is involved in the folding and assembly of newly synthesized polypeptide chains and in preventing the aggregation of stress-denatured proteins.
DnaK(amino acids1-384) is N-terminal ATPase domain and ATP bound to the ATPase domain induces a conformational change in the substrate binding domain (residues 385-638). The protein coding region of the ATPase domain of DNAK (amino acids 1-384) was amplified by PCR and cloned into an E. coli expression vector. The ATPase domain of DNAK was purified to apparent homogeneity by using conventional column chromatography techniques.

Dynein light chain Tctex-type 1 (DYNLT1) is a member of the dynein light chain Tctex-type family. DYNLT1 is a dynein light chain involved in cargo binding. DYNLT1 acts as one of several non-catalytic accessory components of the cytoplasmic dynein 1 complex which are believed to be involved in linking dynein to cargos and to adapter proteins that regulate dynein function. Cytoplasmic dynein is a key motor protein complex responsible for minus-end, microtubule-based motile processes. Each dynein complex consists of two heavy chains which have ATPase and motor activities, as well as a group of accessory polypeptides.

Ubiquitin-like-conjugating enzyme ATG10 (ATG10) is a 220 amino acid protein which localizes to the cytoplasm and has a role in autophagy, specifically acting as an E2-like enzyme providing Atg recognition sites during autophagosome synthesis. ATG10 functions as an E2-like enzyme which catalyzes the conjugation of ATG12 to ATG5, which is required for autophagy. In addition, ATG10 interacts with ATG12 in human embryonic kidney cells in the presence of ATG7. ATG10 probably serves as an ATG5-recognition molecule. Furthermore, ATG10 has a role in adenovirus-mediated cell lysis.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is widely used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.

The 23kDa two-domain periplasmic chaperone FIMC from E.coli is vital for the assembly of type-1 pili, which are filamentous, very oligomeric protein complexes anchored to the outer bacterial membrane that mediate adhesion of pathogenic E. coli strains to host cell surfaces and persist in macrophages.

Recombinant Human Cytokeratin 20 His Tag (KRT20) belongs to the keratin family. The keratins are intermediate filament proteins responsible for the structural integrity of epithelial cells and are subdivided into cytokeratins and hair keratins. The type I cytokeratins is comprised of acidic proteins that are organized in pairs of heterotypic keratin chains. KRT20 is a main cellular protein of mature enterocytes and goblet cells and is specifically expressed in the gastric and intestinal mucosa.

CCL4L1 (C-C motif chemokine 4-like) is a member of to intercrine beta (chemokine CC) family. The CCL4L1 protein is similar to CCL4 which inhibits HIV replication in peripheral blood monocytes which express CCR5.

Complement Factor Properdin (CFP) which is a plasma glycoprotein, is a positive regulator of the alternative complement pathway of the innate immune system. CFP binds and stabilizes the C3- and C5-convertase enzyme complexes in a feedback loop that eventually ends with formation of the membrane attack complex and lysis of the target cell. Mutations in CFP lead to 2 forms of properdin deficiency that cause high susceptibility to meningococcal infections.

Geminin is a 25 kDa nuclear protein, which inhibits DNA replication and is degraded during the mitotic phase of the cell cycle. Geminin controls replication by binding to the licensing factor Cdt1, and is involved in neural differentiation. In addition, Geminin directly interacts with Six3 and Hox homeodomain proteins during embryogenesis and inhibits their functions. Geminin can also promote DNA replication. Geminin has 2 roles in 2 different stages of the cell cycle: Geminin is a negative regulator of DNA replication during the “S phase” of the cell cycle. Inhibition of Geminin during the “S phase” (by RNAi) results in an additional round of replication of portions of the genome. During the “M phase” of the cell cycle (mitosis) Geminin stabilizes the replication factor Cdt1 promoting DNA replication during the next cell cycle. Moreover, inhibition of Geminin during mitosis (by RNAi) causes destabilization of Cdt1 protein and impairment of DNA replication during the next cell cycle. Geminin thus guarantees that only one round of replication occurs during each cell cycle. It was discovered that Geminin is overexpressed in a number of malignancies and cancer cell lines. This maintains the concept that Geminin has also a positive role in DNA replication and cell cycle progression. Geminin accumulates through S, G2 and M phases of the cell cycle but is absent during the G1 phase. During the metaphase/anaphase transition of mitosis Geminin levels decrease.

PSMG4 is a chaperone protein that enhances assembly of the 20S proteasome. PSMG4 cooperates with alpha and beta subunits of the 20S proteasome and with PSMG3 but disconnects when the POMP is recruited before the formation of half-proteasomes.

Protein Tyrosine Phosphatase 1B is the founding member of the protein tyrosine phosphatase (PTP) family, which was isolated and identified based on its enzymatic activity and amino acid sequence. PTPs catalyze the hydrolysis of the phosphate monoesters specifically on tyrosine residues. Members of the PTP family share a highly conserved catalytic motif, which is essential for the catalytic activity. PTPs are known to be signaling molecules that regulate a variety of cellular processes including cell growth, differentiation, mitotic cycle, and oncogenic transformation. This PTP has been shown to act as a negative regulator of INS signaling by dephosphorylating the phosphotryosine residues of INS receptor kinase. This PTP was also reported to dephosphorylate epidermal growth factor receptor kinase, as well as JAK2 and TYK2 kinases, which implicated the role of this PTP in cell growth control, and cell response to IFN stimulation.

MAP1LC3B is a member of the MAP1 LC3 family. MAP1LC3B is a subunit of neuronal microtubule-associated MAP1A and MAP1B proteins, that are involved in microtubule assembly and important for neurogenesis. In addition, MAP1LC3B takes part in formation of autophagosomal vacuoles and is expressed mainly in heart, testis, brain and skeletal muscle.

Ciliary Neurotrophic Factor Receptor, also known as CNTFR is a member of the type I cytokine receptor family. CNTFR binds to CNTF. The alpha subunit provides the receptor specificity. Sole nucleotide polymorphisms in CNTFR has been associated with variations in muscle strength, in addition to early onset of eating disorders.

MAPK3 is a part of the MAP kinase family which is recognized as extracellular signal-regulated kinases (ERKs), that function in a signaling cascade that controls various cellular procedures such as proliferation, differentiation, and cell cycle progression in reaction to a variety of extracellular signals. MAPK3 is activated by upstream kinases, resulting in its translocation to the nucleus where it phosphorylates nuclear targets.

XIAP Associated Factor 1 (XAF1) is a protein which binds to and counteracts the inhibitory effect of a member of the IAP (inhibitor of apoptosis) protein family. IAP proteins bind to and inhibit caspases which are activated in the course of apoptosis. The ratio of IAPs and proteins which interfere with their activity, such as the XAF1 protein, influence the progress of the apoptosis signaling pathway. Additionally, XAF1 inhibits anti-caspase activity of BIRC4. XAF1 induces cleavage and inactivation of BIRC4 independent of caspase activation. Furthermore, XAF1 mediates TNF-alpha-induced apoptosis and is involved in apoptosis in trophoblast cells.

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 and insulin resistance. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity to insulin. Steppan et al. have suggested that resistin suppresses the ability of insulin to stimulate glucose uptake. 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.

CFI cleaves and inactivates C3b and C4b. CFI is inactive without a cofactor such as the soluble factor H and C4b binding protein. CFI cleaves the alpha-peptide chain of C3b and C4b when these binds1 of the cofactors. This cleavage inactivates all of the complement activating functions of these proteins producing iC3b and iC4b.CFI cleaves the alpha chain of C3b twice and this releases a small fragment called C3f. CFI can cleave iC3b releasing C3c from C3dg in the presence of CR1.C4b is cleaved rapidly at 2 sites separating C4c from C4d.

COMP is a non-collagenous glycoprotein and is belongs to the thrombospondin family of extracellular proteins. COMP is a calcium-binding protein of high molecular weight (>500kDa) found in the extracellular matrix of articular, nasal and tracheal cartilage. COMP is not only cartilage-derived but is common in other tissues, such as synovium and tendon. Intact COMP is pentameric, with 5 equal subunits and the carboxy-terminal globular domain of native COMP binds to collagens I, II, and IX. COMP molecules are vital for conserving the properties and integrity of collagen network. Moreover, COMP has a storage and delivery function for hydrophobic cellsignaling molecules such as vitamin D. Mutations of the COMP gene cause Pseudoachondroplasia and some forms of multiple epiphyseal dysplasia which implicates that it is vital that COMP develops and functions normally.

Collagen, a major component of the extracellular matrix, is a fibrous protein that provides tensile strength to tissues giving them structural integrity. Collagen and its derivative, gelatin, have been widely used in medical, pharmaceutical and consumer products for more than 100 years. The supply of these materials, created from animal remains, is both abundant and inexpensive. However, most formulations are not highly purified and have the potential to cause an inflammatory reaction in some product users. In addition, concerns have been raised over the last several years about the potential for contamination of bovine products with the agent that causes mad cow disease and its human variant, Creutzfeldt-Jakob Disease. Animal collagens are subject to extensive modifications that continue over the life of the molecule in the extracellular space. These differences influence both the extractability of collagens from tissue and the biophysical characteristics of these collagens. As a result, collagens isolated from tissues exhibit significant lot-to-lot variability and, as bulk materials, are often analytically intractable. Products that contain animal-derived collagen can induce potentially harmful inflammatory or immune responses in humans and pose risk of contamination with viruses or prions, potentially life-threatening pathogens. Recombinant collagens are essentially identical to the native collagen protein thereby reducing the risk of inflammation, immune response, and disease as compared to animal-sourced collagen.

Carboxyl ester lipase also known as CEL, formely called cholesterol esterase or bile salt-stimulated lipase, is an enzyme with lipolytic capablity of hydrolyzing cholesteryl esters, tri-, di-, and mono- phospholipids, acylglycerol, ceramide and lysophospholipids. The carboxyl terminus of the enzyme controls enzymatic activity by creating hydrogen bonds with the surface loop to partlyshield the active site. The active catalytic site triad of serine-histidine-aspartate is centrally located in the enzyme structure and is partly covered by a surface loop. Bile salt binding to the loop domain set free the active site for accessibility by water-insoluble substrates. CEL is produced mainly in the pancreas and lactating mammary gland, thus the protein is also expressed in liver, macrophages, and in the vessel wall.