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S100 calcium binding protein A5 (S100A5) belongs to the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 family members are localized in the cytoplasm and/or nucleus of a wide range of cells, and are involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. S100A5 has a Ca2+ affinity 20-100 fold higher than the other S100 proteins investigated under identical conditions. Furthermore, S100A5 protein binds Zn2+ and Cu2+, and Cu2+ strongly which harms the binding of Ca2+. S100A5 is expressed in very limited regions of the adult brain.

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.

NNMT is part of the family of transferases, especially those transferring one-carbon group methyltransferases. NNMT is mostly expressed in the liver, and a lower expression is seen in the kidney, lung, skeletal muscle, placenta and heart. NNMT catalyzes the N-methylation of nicotinamide and other pyridines to form pyridinium ions. This activity is significant for biotransformation of many drugs and xenobiotic compounds. NNMT is accountable for the enzymatic activity which uses S-adenosyl methionine as the methyl donor. NNMT expression is related with tumor stage and DFS time in hepatocellular carcinoma cases. NNMT is a good candidate as a tumor marker of various kinds of cancers. NNMT serum levels have significance in the premature detection and in the management of patients with colorectal cancer.

The Defensin family are highly similar in their protein sequence and are microbicidal & cytotoxic peptides made by neutrophils. Beta Defensin-1 is an antimicrobial peptide having the resistance of epithelial surfaces to microbial colonization. Beta Defensin-1 has close proximity to Defensin Alpha-1 and has been implicated in the pathogenesis of cystic fibrosis.
Skin of patients having atopic dermatitis patients and mycosis fungoides (non-lesional and lesional) show lower human Beta Defensin-1 mRNA expression and higher human Beta Defensin-2 and human Beta Defensin-3 mRNA expression.
Beta Defensin is highly expressed by epithelial cells.
Beta-defensin 1 may play a role in the pathogenesis of severe sepsis.

Resistin, a product of the RSTN gene, is a peptide hormone belonging to the class of cysteine-rich secreted proteins (monomeric peptide contains 11 cysteine residues) referred to as the RELM family, and is also described as ADSF (Adipose Tissue-Specific Secretory Factor) or FIZZ3 (Found in Inflammatory Zone 3). Mouse resistin is expressed as a 114 amino acid prepeptide; its hydrofobic Nterminal 20 amino acid signal peptide is cleaved before its secretion. Mouse resistin circulates in blood as a homodimeric protein consisting of two 94 amino acid polypeptides, which are disulfide-linked via Cys26.
Resistin may be an important link between obesity. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity. Steppan et al. have suggested that resistin suppressed the ability to stimulate glucose uptake. They have also suggested that resistin was present at elevated levels in blood of obese mice, and was down regulated by fasting and by antidiabetic drugs. Way et al., on the other hand, have found that resistin expression is severely suppressed in obesity.
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.

Amino-terminal enhancer of split (AES) is a member of the groucho/TLE family of proteins. AES can function as a homooligomer or as a heteroologimer with other family members in order to forcefully repress the expression of other family member genes. Furthermore, AES can repress NFkB-regulated gene expression and is believed to have a significant role in initiating and maintaining cell differentiation events. AES is similar in sequence to the amino terminus of Drosophila enhancer of split groucho, a protein which is involved in neurogenesis during embryonic development. The AES protein is expressed predominately in the fetal brain, liver, lung, heart and kidney and also in the adult muscle.

Cystatin-A is the intracellular inhibitor of cysteine proteinase cathepsin B (CatB) and belongs to family 1 of the cystatin superfamily of inhibitor proteins. CSTA is a stefin that functions as a cysteine protease inhibitor, forming tight complexes with papain and the cathepsins B, H, and L. It has been proposed that extracellular CatB together with other classes of proteinases are all subjected to a cascade-like manner of activation. CatB and its inhibitor Cystatin-A are involved in degradation of extracellular matrix proteins during tissue remodeling. CSTA is one of the precursor proteins of cornified cell envelope in keratinocytes and plays a role in epidermal development and maintenance. Cystatin-A has been reported to be found in high concentrations in epithelial cells, polymorphonuclear leukocytes and lymphoid tissue. Stefins may be used as prognostic and diagnostic tools for cancer.

OTOR proteins is also known as fibrocyte-derived protein (Fdp) and Melanoma inhibitory activity-like (MIAL). Otoraplin is a member of the melanoma-inhibiting activity gene family. Otoraplin is a secreted 16 kDa globular protein that is expressed in the inner ear by periotic mesenchyme and developing and mature fibrocytes. OTOR is highly homologous to MIA/cartilage-derived retinoic acid-sensitive protein (CD-RAP), which is a cartilage-specific protein that is also expressed in malignant melanoma cells. The 111 amino acid mature human otoraplin contains 1 SH3 domain (46 – 107 amino acids) and a Tyr at position 50 that is reportedly sulfated. Otoraplin takes pasrt in the initiation of periotic mesenchyme chondrogenesis.
Otoraplin is secreted through the Golgi apparatus and plays a role in cartilage development and maintenance. A frequent polymorphism in the translation start codon of OTOR can abolish translation and may be associated with forms of deafness.

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.

Pleiotrophin (Osteoblast-Specific Factor-1, OSF-1) contains 136 amino acid residues. The sequence is very rich in cationic amino acids (24% of the residues); lysine cluster sequences are found in the N-terminal and C-terminal ends of the structure.
The OSF-1 gene was shown by Northern blotting analysis to be expressed in mouse calvarial osteoblast-enriched cells and in mouse brain tissues, but not in thymus, spleen, kidney, liver, lung, testis or heart. Pleiotrophin has the ability to promote adhesion, migration, expansion, and differentiation of human osteoprogenitor cells. In addition to certain types of cancer, the embryonic growth and differentiation factor pleiotrophin is found also in adults in inflammatory diseases. In osteoarthritis, pleiotrophin is especially expressed in early stages, and its concentrations in the synovial fluid could serve as a marker for the progress of the disease. Pleitrophin might be involved in cartilage repair in osteoarthritis, in particular, in earlier stages.

MMP10 (Matrix Metallopeptidase 10) which is a part of the matrix metalloproteinase (MMP) is activating procollagenase. MMP10 is part of a cluster of MMP genes which localize to chromosome 11q22.3. MMP10 takes part in the breakdown of extracellular matrix in normal physiological processes, like embryonic development, reproduction, and tissue remodeling, as also in disease processes, such as arthritis and metastasis. The majority MMP's are secreted as inactive proproteins that are activated when cleaved by extracellular proteinases. MMP10 encodes an enzyme which degrades proteoglycans and fibronectin.

PSMD9 is a multicatalytic proteinase complex with a highly ordered structure composed of 2 complexes, a 20S core and a 19S regulator. PSMD9 acts as a chaperone through the assembly of the 26S proteasome, specifically of the base subcomplex of the PA700/19S regulatory complex (RC). During the base subcomplex compilation, PSMD9 is part of an intermediate PSMD9:PSMC6:PSMC3 module, also called modulator trimer complex. PSMD9 is released during the further base assembly process.

FHIT enzyme cleaves adenosine 5'' PPP 5'' A to yield AMP and ADP. FHIT gene includees the regular fragile site FRA3B on chromosome 3. Alterations and deletions of the FHIT gene are highly linked to the genesis and establishment of human tumors of the lung, cervix, breast, colon, stomach and pancreas. In normal cells, FHIT functions as a tumor suppressor and physically relates with ubiquitin conjugating enzyme 9.

CRYGD is a member of the beta/gamma-crystallin family. Crystallins are the principal structural components of the vertebrate eye lens. The mammalian lens crystallins are divided into alpha, beta, and gamma families. Gamma-crystallins are involved in cataract formation. Defects in the CRYGD gene are responsible for cataract autosomal dominant (ADC), cataract congenital non-nuclear polymorphic autosomal dominant (CCP), cataract congenital cerulean type 3 (CCA3) and cataract crystalline aculeiform (CACA).

The proteasome is a multicatalytic proteinase complex which holds an extremely organized 20S core structure shaped like a ring. The central structure is assembled from 4 rings of 28 non-identical subunits; 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. There is a high concentration of proteasomes all over the eukaryotic cells and their job is to cleave peptides in an ATP/ubiquitin-dependent procedure in a non-lysosomal pathway. PSMA3 encodes several of the peptidase T1A family which is a 20S core alpha subunit. Two alternative transcripts encoding diverse isoforms were recognized.

Intein is a section of a protein which can remove itself and return the remaining segment with a peptide bond. In addition, Inteins hold an endonuclease domain which takes part in Intein proliferation. Actually, various genes have unrelated intein-coding segments inserted at altered positions and they were found in all three domains of life (eukaryotes, bacteria, and archaea) and in viruses.

PPIF is a part of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIF accelerates the folding of proteins. It catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides. PPIF is key component of the mitochondrial permeability transition pore in the inner mitochondrial membrane. Activation of this pore is thought to be involved in the induction of apoptotic and necrotic cell death.

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, eosinophils and 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.

SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor.
The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

METTL21A, which is a part of the methyltransferase superfamily, is a Protein-lysine methyltransferase that in vitro methylates HSPA1, HSPA5 and HSPA8.

SGTA is a ubiquitously expressed protein that contains three TPR protein-protein interaction duplicates. SGTA takes part as a component of the androgen receptor (AR)-chaperone-cochaperone complex, functions as a cochaperone and participates in androgen signaling. SGTA binds directly to HSC70 and HSP70 and mediates their ATPase activity. SGTA gene encodes a protein that is able to interact with the chief nonstructural protein of parvovirus H-1 and 70-kDa heat shock cognate. In addition, SGTA interacts with Vpu and Gag from HIV-1, SARS-CoV accessory protein 7a, DNAJC5 and DNAJC5B. Since this transcript is expressed universally in several tissues, SGTA serves a housekeeping function. While being involved in apoptosis and androgen signaling, SGTA is a possible molecule for polycystic ovary syndrome, a disorder characterized by androgen excess, obesity and menstrual disturbances.