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Thioredoxins are small disulphide-containing redox proteins (within the conserved Cys-Gly-Pro-Cys active site) that have been found in all the kingdoms of living organisms. Thioredoxin contains a single disulfide active site and serves as a general protein disulphide oxidoreductase. Thioredoxins are involved in the first unique step in DNA synthesis. It interacts with a broad range of proteins by a redox mechanism based on reversible oxidation of two cysteine thiol groups to a disulphide, accompanied by the transfer of two electrons and two protons. The net result is the covalent interconversion of a disulphide and a dithiol. It has been suggested that thioredoxin may catalyze the formation of correct disulfides during protein folding because of its ability to act as an efficient oxidoreductant. Trx also provides control over a number of transcription factors affecting cell proliferation and death through a mechanism referred to as redox regulation.

Clathrin, light chain A (CLTA) is a member of the clathrin family. Clathrin, which is a large, soluble protein, is comprised of heavy and light chains. CLTA is one of 2 clathrin light chain proteins which are supposed to function as regulatory elements. CLTA is a key cytosolic coat protein in pits and vesicles originating from the plasma membrane and the trans-Golgi network. In receptor-mediated endocytosis, receptor proteins are encapsulated by Clathrin-coated vesicles.

TNF-related apoptosis-inducing ligand (TRAIL) is a ligand molecule which induces apoptosis. It is a type II transmembrane protein with homology to other members of the tumor necrosis factor family.
In humans, the gene that encodes for TRAIL is located at chromosome 3q26. TRAIL binds to the death receptors, DR4 and DR5. The process of apoptosis is caspase-8-dependent. This protein preferentially induces apoptosis in transformed and tumor cells, but does not appear to kill normal cells although it is expressed at a significant level in most normal tissues.

TBC1 domain family member 22B, also known as TBC1D22B acts as a GTPase-activating protein for Rab family protein. The Tre-2/Bub2/Cdc16 (TBC) domain is a conserved protein motif which consists of roughly 200 amino acids and functions as a specific Rab-GAP domain. The TBC domain has more than 40 distinct TBC domain-containing proteins which have been identified in humans.

HIV-1, the causative agent of acquired immunodeficiency syndrome (AIDS), contains an RNA genome which produces a chromosomally integrated DNA during the replicative cycle. Activation of HIV-1 gene expression by the transactivator Tat is dependent on an RNA regulatory element (TAR) located downstream of the transcription initiation site. TARDBP is a transcriptional repressor which binds to chromosomally integrated TAR DNA and represses HIV-1 transcription. In addition, TARDBP regulates alternate splicing of the CFTR gene. A similar pseudogene is present on chromosome 20.

Killer-cell immunoglobulin-like receptors (KIRs), are a family of cell surface glycoproteins found on Natural Killer (NK) Cells, which are important cells of the immune system. They control the killing function of these cells by interacting with MHC class I molecules, which are expressed on all cell types. This interaction allows them to identify virally infected cells or tumor cells that have a distinctive low level of Class I MHC on their surface. The majority of KIRs are inhibitory, which means that their recognition of MHC suppresses the cytotoxic activity of their NK cell. Only a limited number of KIRs have the capacity to activate cells. The KIR genes are found in a cluster on chromosome 19q13.4 within the 1 Mb leukocyte receptor complex (LRC). KIR molecules are extremely polymorphic, meaning their gene sequences differ significantly between individuals, so that different individuals have different arrays/repertoires of KIR genes. The KIR proteins are categorized by the number of

TNFR1 belongs to the TNF-receptor superfamily. TNFR1 is a receptor for TNFSF2/TNF-alpha and homotrimeric TNFSF1/lymphotoxin-alpha.
There are 2 types of soluble TNF receptors: sTNFR-I and sTNFR-II, which act to neutralize the biological activities of TNF alpha and TNF beta. The levels of these soluble receptors seem to increase as a result of shedding of the extracellular domains of the membrane bound receptors. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.
TNFR1 is capable of signaling both cell survival and apoptosis. TNFR1-induced apoptosis requires 2 sequential signaling complexes. TNFR1 is capable of activating NF-kappaB, mediate apoptosis, and function as a regulator of inflammation. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNFR1 contributes to the induction of non-cytocidal TNF effects including anti-viral state and activation of the acid sphingomyelinase. Human TNFR1 has a major region which controls cell surface expression. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women.
Germline mutations of the extracellular domains of TNFR1 are linked to the autosomal dominant periodic fever syndrome. The impaired receptor clearance is believed to be a mechanism of the disease. Familial hibernian fever (FHF) is caused by defects in TNFRSF1A gene.

Myelin Protein Zero-Like 1 (MPZL1) is a cell surface receptor, which is involved in signal transduction processes. MPZL1 recruits PTPN11/SHP-2 to the cell membrane and is a putative substrate of PTPN11/SHP-2. MPZL1 is a main receptor for concanavalin-A (ConA) and it is involved in cellular signaling induced by ConA, which most likely includes Src family tyrosine-protein kinases. MPZL1 Isoform 3 appears to have a dominant negative role by blocking tyrosine phosphorylation of MPZL1 induced by ConA. Isoform 1, but not isoform 2 and isoform 3, might be involved in regulation of integrin-mediated cell motility.

Thymidine kinase 2 mitochondrial (TK2) is a member of the DCK/DGK family. TK2 is an enzyme, a phosphotransferase (a kinase): 2'-deoxythymidine kinase, ATP-thymidine 5'-phosphotransferase. Thymidine kinase is found in most living cells. Thymidine kinase is present in 2 forms in mammalian cells, TK1 and TK2. Thymidine kinases have a central function in the synthesis of DNA and thus in cell division, since they are part of the exceptional reaction chain to introduce deoxythymidine into the DNA. TK2 is a deoxyribonucleoside kinase which specifically phosphorylates thymidine, deoxycytidine, and deoxyuridine. TK2 localizes to the mitochondria and is essential for mitochondrial DNA synthesis. TK2 gene defects are a cause of mitochondrial DNA depletion syndrome type 2 (MTDPS2).

KH homology domain containing 1-like, also known as KHDC1L is a member of the KHDC1 family.KHDC1L is a protein-coding gene; an important paralog of this gene is KHDC1.

Mmitochondrial import receptor subunit TOMM20 homolog (TOMM20) is a member of the Tom20 family. The Tom machinery consists of import receptors for the initial binding of cytosolically synthesized preproteins and a general import pore (GIP) for the membrane translocation of various preproteins into the mitochondria. TOMM20 acts as the transit peptide receptor at the surface of the mitochondrion outer membrane and facilitates the movement of preproteins into the TOM40 translocation pore.

Cysteine-Rich Secretory Protein 2 (CRISP2) regulates some ion channels activity and thereby regulates calcium fluxes during sperm capacitation. Amongst its related pathways are p53 signaling. Diseases related with CRISP2 include epididymitis and orchitis.

Reticulocalbin-2 (RCN2) is a member of the CREC protein family. RCN2 is a calcium-binding protein found in the lumen of the ER. RCN2 contains 6 conserved regions with similarity to a high affinity Ca(+2)-binding motif, the EF-hand.

Killer cell immunoglobulin-like receptor 2DL5A or KIR2DL5A is part of the killer cell Ig-like receptor (KIR) family. KIR2DL5A is atype I transmembrane glycoprotein. The protein is detected on the cell membrane as a monomer who, once tyrosine is phosphorylated, recruits the Src homology region 2-includes protein tyrosine phosphatase-2. Hence, KIR2DL5A is an inhibitory receptor gathering a combination of genetic, structural, and functional features unique among KIR, suggesting that KIR2DL5A plays a crucial role in innate immunity.

TUBB2B is a beta isoform of tubulin, which binds GTP and is a major component of microtubules. Numerous beta Tubulin isoforms have been characterized and are expressed in mammalian tissues. Tubulin binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha-chain. TUBB2b is mostly expressed in developing neurons with a dominant expression during the critical steps of corticogenesis. In addition, TUBB2B is a new critical gene involved in neuronal migration. TUBB2B is present in the nuclei and nucleoplasm, Defects in the TUBB2B gene are a cause of asymmetric polymicrogyria.

Lipopolysaccharide is a potent stimulator of monocytes and macrophages, causing secretion of tumor necrosis factor-alpha (TNF-alpha) and other inflammatory mediators. LITAF is a lipopolysaccharide-induced TNF-alpha factor, which is a DNA-binding protein and can mediate the TNF-alpha expression by direct binding to the promoter region of the TNF-alpha gene. The transcription of the LITAF gene is induced by tumor suppressor p53 and has been implicated in the p53-induced apoptotic pathway. Mutations in the LITAF gene cause Charcot-Marie-Tooth disease type 1C (CMT1C) and may be involved in the carcinogenesis of extramammary Paget''s disease (EMPD).

Crk-like protein (CRKL) is a protein kinase containing SH2 and SH3 (src homology) domains which activates the RAS and JUN kinase signaling pathways and transforms fibroblasts in a RAS-dependent manner. CRKL is a substitute of the BCR-ABL tyrosine kinase, it also has a role in fibroblast transformation by BCR-ABL, and has oncogenic potential.

CTLA-4 is a member of the immunoglobulin superfamily and encodes a protein which transmits an inhibitory signal to T cells. The protein contains a V domain, a transmembrane domain, and a cytoplasmic tail. Alternate transcriptional splice variants, encoding different isoforms, have been characterized. The membrane-bound isoform functions as a homodimer interconnected by a disulfide bond, while the soluble isoform functions as a monomer. Mutations in this gene have been associated with ins.-dependent diabetes mellitus, Graves disease, Hashimoto thyroiditis, celiac disease, systemic lupus erythematosus, thyroid-associated orbitopathy, and other autoimmune diseases.

Cathepsin-L also known as CTSL is a member of the peptidase C1 family. CTSL, is a dimer composed of disulfide-linked heavy and light chains, both formed from a single protein precursor. Furthermore, CTSL is a lysosomal cysteine proteinase which takes a main part in intracellular protein catabolism. CTSL substrates include collagen and elastin, as well as alpha-1 protease inhibitor, which is the most important controlling element of neutrophil elastase activity. CTSL has been implicated in a number of pathologic processes, including myofibril necrosis in myopathies and in myocardial ischemia, and in the renal tubular response to proteinuria. Multiple alternatively spliced transcript variants have been found for CTSL.

Serine/threonine-protein kinase 16 (STK16) is a membrane-associated protein kinase which phosphorylates on serine and threonine residues. STK16 is involved in secretory vesicle trafficking or intracellular signaling. Furthermore, the STK16 protein may have a role in regulating stromal-epithelial interactions which occur during ductal morphogenesis in the mammary gland. STK16 can autophosphorylate on Tyr residue; it is however unclear whether STK16 has tyrosine-protein kinase toward other proteins. STK16 may also be involved in TGF-beta signaling.

CD207 (C-type lectin domain family 4 member K) is expressed in Langerhans cells which are immature dendritic cells of the epidermis and mucosa. Moreover, CD207 is expressed in several other dendritic cell types including dermal CD103+ DCs and splenic CD8+ DCs. Langerin is localized in the Birbeck granules, the organelles present in the cytoplasm of Langerhans cells and comprised of superimposed and zippered membranes. CD207 is a C-type lectin with mannose binding specificity, and it has been suggested that mannose binding by the CD207 protein leads to internalization of antigen into Birbeck granules thus providing access to a nonclassical antigen-processing pathway.

Tumor Protein P53 Regulated Apoptosis Inducing Protein 1 (TP53AIP1) is expressed mainly in the thymus, and is localized to the mitochondrion. p53 induces TP53AIP1 production which then mediates p53- dependent apoptosis. Alternatively spliced transcript variants encoding diverse isoforms are known for TP53AIP1.

CDC123 is a member of the CDC123 family. CDC123is required for S phase entry of the cell cycle. It is also broadly expressed in spleen,thymus, prostate, testis, ovary, small intestine, colon and leukocytes with the uppermost expression in testis.

IL-12 is a heterodimeric cytokine that stimulates the production of IFNgamma from T-cells and natural killer cells, and also induces differentiation of Th1 helper cells. IL-12 is an initiator of cell-mediated immunity.