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Otubain 1 (OTUB1) belongs to the ovarian tumor (OUT) superfamily of predicted cysteine proteases and inhibits cytokine gene transcription in the immune system through its interaction with a ubiquitin protease and E3 ubiquitin ligase. OTUB1 is a highly specific ubiquitin iso-peptidase, it cleaves ubiquitin from branched poly-ubiquitin chains but not from ubiquitinated substrates. OTUB1 is believed to work in specific ubiquitin-dependent pathways, possibly by providing an editing function of polyubiquitin chain growth. OTUB1 is a hydrolase that removes conjugated ubiquitin from proteins in vitro and may therefore have a significant regulatory role in the level of protein turnover by preventing degradation. Additionally, OTUB1 is a regulator of T-cell anergy, a phenomenon that occurs when T-cells are rendered impassive to antigen re-challenge and no longer respond to their cognate antigen. OTUB1 acts via its interaction with RNF128/GRAIL, which is an essential inductor of CD4 T-cell anergy.

Recombinant Fatty Acid Binding Protein is a newly introduced plasma marker of acute myocardial infarction (AMI). The plasma kinetics of FABP (15kD) closely resemble those of myoglobin in that elevated plasma concentrations are found within 2 hours after AMI and return to normal generally within 18 to 24 hours. But the concentration of FABP in the skeletal muscle is 20 times lower than in cardiac tissue (for myoglobin the same content for cardiac and skeletal tissue), that makes FABP to be more cardiac specific than myoglobin. This makes FABP a useful biochemical marker for the early assessment or exclusion of AMI. FABP also appears to be a useful plasma marker for the estimation of myocardial infarct size.

EXOSC1 is a non-catalytic component of the exosome which has 3'->5' exoribonuclease activity and participates in many cellular RNA processing and degradation occasions. EXOSC1 associates with the exosome by protein-protein interactions with ribosomal RNA-processing protein 42 and ribosomal RNA-processing protein 46.

Matrix metalloproteinases are a family of zinc and calcium-dependent endopeptidases that break down extracellular matrix proteins. The MMP9 is secreted as a 92kDa zymogen. Cleavage of ProMMP-9 results in the active enzyme, having a molecular weight of approximately 82kDa. MMP9 is composed of the following domains: a gelatin-binding domain consisting of three fibronectin type II units, a catalytic domain containing the zinc-binding site, a proline-rich type V collagen-homologous domain and a hemopexin-like domain. MMP9 is produced by the several cell types: monocytes, macrophages, neutrophils, keratinocytes, fibroblasts, osteoclasts and endothelial cells. MMP9 is involved in inflammatory responses, tissue remodeling, wound healing, tumor growth and metastasis. MMP9 may also play an important part in local proteolysis of the extracellular matrix and in leukocyte migration, as well as in bone osteoclastic resorption. MMP9 cleaves type IV and type V collagens into large C-terminal three quarter fragments and shorter N-terminal one quarter fragments. MMP9 can also degrade fibronectin but not laminin or Pz-peptide.
MMP9 defects may be a cause of susceptibility to intervertebral disc disease (IDD), also known as lumbar disk herniation (LDH).

Prosaposin (PSAP) is a precursor of 4 lysosomal saposin proteins (saposin A, B, C and D). Saposins are heat-stable glycoproteins which facilitate the catabolism of glycosphingolipids with short oligosaccharide groups. PSAP stimulates neurite outgrowth and increases choline acetyltransferase activity. Prosaposin exists both as a secretory protein and as an integral membrane protein and has neurotrophic activities. The secreted prosaposin is assumed to have additional functions in human milk, cerebrospinal fluid and seminal plasma. PSAP gene mutations are linked with Gaucher disease, Tay-Sachs disease, and metachromatic leukodystrophy.

RAB1A belongs to the ras-related superfamily. Rab proteins have a central part in either in endocytosis or in biosynthetic protein transport. Rab1a protein controls vesicle traffic from the endoplasmic reticulum to the Golgi apparatus.

Protein phosphatase 1 regulatory subunit 11 (PPP1R11) is located within the major histocompatibility complex class I region on chromosome 6 and is expressed in a variety of both adult and embryonic tissues. PPP1R11 acts as an inhibitor of PP1 (protein phosphatase 1), particularly showing a sensitivity toward the metal-independent and metal-dependent forms of PP1. Deletion of a portion of the q arm of chromosome 6 is related with early onset intestinal cancer, proposing the presence of a cancer vulnerability locus.

g-synuclein(Originally known as a breast cancer specific gene product, BCSG1) is an acidic neuronal protein of 127 amino acids. Gamma-Synuclein is a member of the Synuclein protein family, which is believed to be involved in the pathogenesis of neurodegenerative diseases. High levels of Gamma-Synuclein have been found in advanced breast carcinomas suggesting a correlation between overexpression of SNCG and breast tumor development. Synuclein-Gamma is found mostly in the peripheral nervous system (in primary sensory neurons, sympathetic neurons, and motor neurons) and retina. SNCG is also identified in the brain, ovarian tumors, and in the olfactory epithelium. SNCG expression in breast tumors is a marker for tumor progression. A modification in the expression of gamma-synuclein has been detected in the retina of Alzheimer's patients.

Human Cystatin A (CSTA or Stefin A) belongs to family 1 of the cystatin superfamily, which is characterized by the lack of disulphide bonds and carbohydrates. CSTA is an intracellular inhibitor regulating the activities of cysteine proteases of the papain family such as Cathepsins B, H and L. Cystatin A has also been implicated in several disease states. Because of altered proteolytic state in cancer progression, CSTA may have a role in the proteolitic pathways.

TSFM is a mitochondrial translation elongation factor which is linked with the EF-Tu.GDP complex and induces the exchange of GDP to GTP. TSFM stays bound to the aminoacyl-tRNA.EF-Tu.GTP complex until the GTP hydrolysis stage on the ribosome. Mutations in TSFM are related with combined oxidative phosphorylation deficiency-3 syndrome.

Sterile Alpha Motif Domain Containing 13 (SAMD13) is a putative protein interaction module which is present in various proteins involved in numerous biological processes. SAMD13 contains one SAM (sterile alpha motif) domain. The SAM domain, which spreads over around 70 residues, is found in various eukaryotic organisms. SAM domains are known to homo- and hetero-oligomerise, forming multiple self-association constructions and also binding to various non-SAM domain-containing proteins, however with a low affinity constant.

Osteoclasts are multinucleated cells that resorb bone and are essential for bone homeostasis. OSCAR plays crucial roles in the regulation of the innate and adaptive immune responses.Unlike the other LRC members, OSCAR expression is found specifically in preosteoclasts or mature osteoclasts. OSCAR is an important bone-specific regulator of osteoclast differentiation. Multiple alternative splicing transcript variants encodes different isoforms have been found for this gene.

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.

SOS1, also known as Gingival Fibromatosis, is a Ras & Rac guanine nucleotide exchange factor. SOS1 is comprised of a number of significant domains. The REM and CDC25 domains provide the catalytic activity of SOS1 towards Ras and the histone fold DH/PH (Dbl homology & Pleckstrin homology) domains function, in tandem, to stimulate GTP/GDP exchange for Rac. Moreover, binding of GTP activates Ras proteins, and subsequent hydrolysis of the bound GTP to GDP and phosphate inactivates signaling by these proteins. GTP binding can be catalyzed by guanine nucleotide exchange factors for RAS, and GTP hydrolysis can be enhanced by GTPase-activating proteins.

Integrin Beta 3 Binding Protein (ITGB3BP1) is a broadly expressed protein which contains a DD1 or RepD1 domain and an LXXLL motif. ITGB3BP1 functions as a nuclear receptor coactivator while induced by estrogen. ITGB3BP1 is also relates with the CENP-A-CAD complex that is engaged in mitotic progression, the assembly of kinetochore proteins and chromosome segregation. ITGB3BP1 behave s as a transcriptional corepressor via its interaction with the NFKB1 NF-kappa-B subunit by interfering with the transactivation domain of NFKB1.

CMC4 is a downstream 8kDa protein restricts to mitochondria which was identified by participation in some t(X;14) translocations related with mature T-cell proliferations. This region has a compound gene structure, with a common promoter and 5’ exon spliced to two different groups of 3’ exons which encode 2 separate proteins.

HSP10 is part of the molecular chaperons, that are crucial for thir efficient folding of proteins in normal as well as stress conditions. GroES function is to bind to HSP60 in the presence of ATP, thus causing a change in the HSP60 conformation & enclosing the protein substrate within the complex. ATP hydrolysis by chaperonin-60 which destabilizes the HSP10-HSP60 complex, thereby allowing it to dissociate and secrete the substrate protein. GroES having the NCBI accession number of NP_002148 was purified by using conventional chromatography techniques.

MICA (MHC class I chain-related gene A) is a transmembrane glycoprotein that functions as a ligand for human NKG2D. A closely related protein, MICB, shares 85% amino acid identity with MICA. These proteins are distantly related to the MHC class I proteins. They possess three extracellular Ig-like domains, but they have no capacity to bind peptide or interact with ?2-microglobulin. The genes encoding these proteins are found within the Major Histocompatibility Complex on human chromosome 6. The MICA locus is highly polymorphic with more than 50 recognized human alleles. MICA is absent from most cells but is frequently expressed in epithelial tumors and can be induced by bacterial and viral infections. MICA is a ligand for human NKG2D, an activating receptor expressed on NK cells, NKT cells,gammadelta T cells, and CD8+beta T cells. Recognition of MICA by NKG2D results in the activation of cytolytic activity and/or cytokine production by these effector cells. MICA recognition is involved in tumor surveillance, viral infections, and autoimmune diseases.

Myosin regulatory light chain 12A (MYL12A) has a vital role in regulation of both smooth muscle and nonmuscle cell contractile activity via its phosphorylation. The MYL12A protein is involved in cytokinesis, receptor capping, and cell locomotion.

Syntaxin is membrane integrated Q-SNARE protein participating in exocytosis. Syntaxin is composed of an N-terminal regulatory domain (Habc), a SNARE domain (known as H3), and a single C-terminal transmembrane domain. The SNARE (H3) domain binds to both synaptobrevin and SNAP-25 forming the core SNARE complex. Synaptic vesicles store neurotransmitters that are released during calcium-regulated exocytosis. The specificity of neurotransmitter release requires the localization of both synaptic vesicles and calcium channels to the presynaptic active zone. Syntaxins function in this vesicle fusion process. Syntaxins also serve as a substrate for botulinum neurotoxin type C, a metalloprotease that blocks exocytosis and has high affinity for a molecular complex that includes the alpha-latrotoxin receptor which produces exocytosis.

Thrombospondin-4 (THBS4) is a member of the thrombospondin protein family. This family members are adhesive glycoproteins that mediate cell-to-cell and cell-to-matrix interactions. THBS4forms a pentamer and binds to heparin and calcium. Among them THBS4binds a variety of matrix proteins including Collagens I, II, III, V, Laminin‑1, Matrilin‑2 and Fibronectin. THBS4 is up‑regulated in the spinal cord following peripheral nerve injury where it contributes to presynaptic hypersensitivity and hyperalgesia and is also up‑regulated in muscle following denervation.

Granulocyte Chemotactic Protein 2 (CXCL6), also known as GCP-2, is a Chemotactic for neutrophil granulocytes. GCP-2 signals through binding and activation of its receptors (CXCR1 and CXCR2). GCP-2 has strong antibacterial activity against Gram-positive and Gram-negative bacteria in addition to its chemotactic and angiogenic property.

S100A4 is a member of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 belongs to the family of calcium binding proteins such as calmodulin and troponin C. S100A is composed of an alpha and beta chain whereas S100B is composed of two beta chains. S100 protein is also expressed in the antigen presenting cells such as the Langerhans cells in skin and interdigitating reticulum cells in the paracortex of lymph nodes. S100 proteins are localized either in the cytoplasm or the nucleus of a wide range of cells. S100 proteins are involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. S100A4 may function in motility, invasion, and tubulin polymerization. There are at least 13 members in the S100 gene family, which are located as a cluster on chromosome 1q21. Chromosomal rearrangements and altered expression of the S100A4 gene have been implicated in tumor metastasis.

TBCA is a tubulin-folding protein which is involved in the early step of the tubulin folding pathway. TBCA is one of four proteins (cofactors A, D, E, and C) implicated in the pathway directing to properly folded beta-tubulin from folding intermediates. Cofactors A and D are thought to be a factor in capturing and stabilizing beta-tubulin in a quasi-native confirmation. TBCA is crucial for cell viability, if reduced it causes a decrease in the amount of soluble tubulin, alterations in microtubules and G1 cell cycle arrest. Cofactor E attaches to the cofactor D-tubulin complex, afterward, interaction with cofactor C triggers the release of tubulin polypeptides that are committed to the native state.