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V-Set Domain Containing T Cell Activation Inhibitor 1, also known as VCTN1, is part of the B7 costimulatory protein family. Proteins in this family are located on the surface of antigen-presenting cells and interact with ligand bound to receptors on the surface of T cells. High level of the encoded protein has been associated with tumor progression. VCTN1 also takes part in promoting epithelial cell transformation.

Signal-transducing adaptor protein 1 (STAP1) acts as a docking protein which operates downstream of Tec tyrosine kinase in B cell antigen receptor signaling. The STAP1 protein is directly phosphorylated by Tec in vitro where it partakes in a positive feedback loop, increasing Tec activity.

Stomatin (STOM) is a part of a highly conserved family of integral membrane proteins. STOM is a membrane protein involved in regulation of monovalent cation transport through lipid membranes which regulates ACCN1 and ACCN3 gating. STOM is a major lipid-raft component of erythrocytes and epithelial cells, and an abundant platelet protein which acts as a cytoskeletal anchor.

Energy Homeostasis Associated (ENHO) participates in glucose homeostasis maintenance and lipid metabolism. ENHO is expressed in the liver and the brain. The role of ENHO in obesity or diabetes is studied.

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.

Microtubule-associated proteins 1A/1B light chain 3 beta 2 (MAP1LC3B2) is a member of the MAP1LC3 family. MAP1LC3B2 is a subunit of neuronal microtubule-associated MAP1A and MAP1B proteins, which are involved in microtubule assembly and essential for neurogenesis. The MAP1LC3B2 protein is possibly involved in formation of autophagosomal vacuoles (autophagosomes). MAP1LC3B2 is expressed primarily in the heart, testis, brain and skeletal muscle.

Alpha crystallins are composed of two gene products ; alpha-A and alpha-B, for acidic and basic, respectively. Alpha crystallins can be induced by heat shock and are members of the small heat shock protein (sHSP also known as the HSP20). They act as molecular chaperones and hold them in in large soluble aggregates. These heterogeneous aggregates consist of 30-40 subunits; the alpha-A and alpha-B subunits have a 3:1 ratio, respectively. Two additional function of a-crystallins are an autokinase activity and participation in the intracellular architecture. Alpha-B is expressed widely in many tissues and organs and occurs in many neurological diseases.

Defensins form a family of microbicidal and cytotoxic peptides made by neutrophils. Members of the defensin family are highly similar in protein sequence. This gene encodes defensin, beta 103A, which has broad spectrum antimicrobial activity and may play an important role in innate epithelial defense.

Ubiquitin is a highly conserved 76 amino acid protein expressed in all eukariotes. Ub is found either in free form or conjugated to proteins as monomer or as chain of ubiquitin molecules. The most well characterized consequence of polyubiquitination is substrate degradation, while mono-ubiquitinated proteins are not degraded. Ubiquitin attachment to protein substrate is a complex process involving a ubiquitin activating enzyme (E1), a ubiquitin conjugating enzyme (E2) and a ubiquitin protein ligase (E3). The first ubiquitin moiety is transferred to the e-NH2 group of a Lys residue of the protein substrate to generate an isopeptide bond. In successive reactions, a poly ubiquitin chain is synthesized by processive transfer of additional activated moieties to Lys48 of the previously conjugated ubiquitin molecule. Ubiquitin K48R prevents the formation of poly ubiquitin chains via Lys48 linkages with mono ubiquitin molecules, avoiding the degradation of protein substrates.

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 tyrosine residues to eventually form the tyrosine O-sulfate ester group in addition to the desulfonated 3’-phosphoadenosine-5’-phosphate.

S100A11 is a member of the S100 family of proteins which contains two EF-hand calcium-binding motifs and is thought to be involved in the regulation of a number of cellular processes including cell cycle progression and differentiation. S100A11 may function in motility, invasion and tubulin polymerisation. S100 proteins are localized either in the cytoplasm or the nucleus of a wide range of cells. 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 S100A11 have been implicated in tumor metastasis.

Microtubule-associated protein tau (MAPT or Tau) is a protein that stabilizes microtubules. MAPT is abundant in neurons in the central nervous system and is less common elsewhere. When MAPT is defective, and no longer stabilizes microtubules properly, it can result in dementias, such as Alzheimer's disease.

GDF-5 is a member of the bone morphogenetic protein (BMP) family and the TGF-beta superfamily. This group of proteins is characterized by a polybasic proteolytic processing site which is cleaved to produce a mature protein containing seven conserved cysteine residues. The members of this family are regulators of cell growth and differentiation in both embryonic and adult tissues. Mutations in this gene are associated with acromesomelic dysplasia, Hunter-Thompson type; brachydactyly, type C; and chondrodysplasia, Grebe type. These associations confirm that the gene product plays a role in skeletal development.

Nectin-1, also referred to as ED4, is a poliovirus receptor- related 1 protein is a part of the Nectin family. Nectin-1 endorses cell-cell contacts by forming homophilic or heterophilic trans-dimers. Heterophilic interactions among PVRL1/nectin-1 & PVRL4/nectin-4 and among PVRL1/nectin-1 & PVRL3/nectin-3 have been found. Nectin-1 acts as an entry receptor for herpes simplex virus & pseudorabies virus as well. Likewise, Neurite outgrowth-promoting activity has been shown by Nectin-1.

C3 is central to the activation of all 3 pathways of complement activation. Initiation of each pathway generates proteolytic enzyme complexes which binds the target surface. These enzymes cleave a peptide bond in C3 releasing the anaphylatoxin C3a and activating C3b. Most of the C3 activated during complement activation never attaches to the surface due to its thioester reaction with water forming fluid phase C3b which is rapidly inactivated by factors H and I forming iC3b. Surface-bound C3b is necessary in all 3 pathways for efficient activation of C5 and formation of C5b-9 complexes that lyse the target cell membrane.

Type 1 cystatins are also called stefins which function as intracellular thiol protease inhibitors. Cystatin-B protein is able to form a dimer stabilized by noncovalent forces, inhibiting papain and cathepsins l, h and b. CSTB protein protects proteases leakage from lysosomes. Mutations in Stefin-B gene cause primary defects in patients with progressive myoclonic epilepsy (EPM1), a degenerative disease of the central nervous system. CSTB is overexpressed & elevated in the serum of HCC patients. Cystatin-B in vivo has a polymeric structure which is sensitive to the redox environment. Cystatin-B inhibits bone resorption by down-regulating intracellular cathepsin K activity despite increased osteoclast survival. Protein and mRNA levels of stefin B are significantly lower in atypical benign meningiomas. Stefins-A & Stefin-B which belong to the type-1 Cystatins, are up-regulated in lung tumours and thus able to counteract harmful tumour-associated proteolytic activity. Human stefin-A & Stefin-B form amyloid fibrils. Copper binding by stefin-B reduces amyloid fibril formation. A number of alternatively spliced CSTB isoforms were recognized in patients with progressive myoclonus epilepsy. Decreased CSTB activity in EPM1 pathogenesis is controled by cathepsins through increased activity of cathepsin-S & cathepsin-L.

Kallikrein-3 (KLK3) is a part of the kallikrein-related peptidase family. Kallikreins are a subgroup of serine proteases having various physiological functions. Numerous kallikreins take part in carcinogenesis and some may be prospective cancer and other disease biomarkers. Kallikrein-3 is 1 of the 15 kallikrein subfamily members located in a cluster on chromosome 19 and is a protease present in seminal plasma. KLK3 hydrolyzes semenogelin-1 consequently leading to the liquefaction of the seminal coagulum. KLK3 acts normally in the liquefaction of seminal coagulum, probably by hydrolysis of the high molecular mass seminal vesicle protein. Serum level of the KLK3 protein, called PSA in the clinical setting, is beneficial in the diagnosis and monitoring of prostatic carcinoma.

CTF2P, aka Neuropoietinis a part of the IL-6 family of cytokines. CTF2P is the outcome of a gene duplication event involving cardiotrophin-1 (CT-1) and it helps to define a subfamily within the IL-6 family that includes CT-1, CLC and CTNF. CTF2P Increases the platelet count associated with splenomegaly and takes part in neuronal precursor development and maturation.

PRMT1 Methylates (mono & asymmetric dimethylation) the guanidino nitrogens of arginyl residues present in a glycine and arginine-rich domain (may methylate HNRNPA1 and histones). Methylates SUPT5H.
The PRMT1 protein functions as a histone methyltransferase specific for H4.
PRMT1 is an essential factor in oncogenesis and is a potential novel therapeutic target in cancer.
PRMT1-mediated methylation serves as a positive modulator of IR/IRS-1/PI3K pathway and glucose uptake in skeletal muscle cells.
CAF1 is a new regulator of PRMT1-dependent arginine methylation.
PRMT1 arginine-methylates MRE11 therefore it regulates the activity of MRE11-RAD50-NBS1 complex during the intra-S-phase DNA damage checkpoint response.
PRMT1 plays a post-translationally part in regulating the transcriptional activity.
PRMT1 is found predominantly in the cytoplasma though a fraction of PRMT1 is located in the nucleus.

ECSIT homolog (ECSIT) is a ubiquitously expressed protein which has a vital role as an adaptor protein in the cytosolic signal transduction cascade events triggered by Toll receptor activation. ECSIT promotes proteolytic activation of MAP3K1. ECSIT is also involved in the BMP signaling pathway. ECSIT is essential for normal embryonic development. ECSIT was originally classified as a cytoplasmic protein interacting specifically with TNF receptor associated factor (TRAF)-6 in the TLR pathway. ECSIT gene knockdown results in gravely impaired complex I assembly and disrupted mitochondrial function.

NF-kappa-B inhibitor-interacting Ras-like protein 1 (NKIRAS1) is a member of the small GTPase superfamily. NKIRAS1 is an unusual Ras-like protein which acts as a potent regulator of NF-kappa-B activity by thwarting the degradation of NF-kappa-B inhibitor beta (NFKBIB) by most signals, describing why NFKBIB is more resistant to degradation. NKIRAS1 functions by blocking phosphorylation of NFKBIB and mediating cytoplasmic retention of p65/RELA NF-kappa-B subunit. Both GTP- and GDP-bound forms block phosphorylation of NFKBIB.

ASS1 is involved in the urea cycle, which is a sequence of chemical reactions that is localized in liver cells. The urea cycle processes excess nitrogen that is generated as the body uses proteins. The surplus nitrogen is used to create a molecule called urea, which is excreted from the body in urine.

Histone is vastly alkaline protein exists in eukaryotic cell nuclei which set and direct the DNA into structural units named nucleosomes. 5 key families of histones are: H1/H5, H2A, H2B, H3, including H4. The core histones are H2A, H2B, H3 and H4, whereas histones H1/H5 are identified as the linker histones. Moreover the dynamics of chromatin structure depend on posttranslational modification of histones in addition to the appearance of different histone variants. Histone H3 as well as H4 are modified covalently at several residues. The histone code is constitute by these and the H2A/H2B modifications.

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.
BBeta Defensin is highly expressed by epithelial cells.
Beta-defensin 1 may play a role in the pathogenesis of severe sepsis.
Variation in human Beta Defensin-1 contributes to asthma diagnosis, with apparent gender-specific effects. Human Beta Defensin-3 is a dimer, while Human BD-1 and Human BD-2 are monomeric. The expression of Human BD1 is correlated with induction profiles in gingival keratinocytes.
The level of expression of human DEFB1 mRNA is lower than that of human BD3 and human BD-2 in reconstructed epidermis.
Human BD1 is down-regulated in human prostatic and renal carcinomas.