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The 14-3-3 family of proteins plays a key regulatory role in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are at least seven isoforms that have been identified in mammals. The 14-3-3gamma, a subtype of the 14-3-3 family of proteins, was thought to be brain and neuron-specific. It has been shown to interact with RAF1 and protein kinase C, proteins involved in various signal transduction pathways.

MHC Class II is consists of 2 membrane spanning proteins. Each of these proteins is roughly 30 kDa, and has of two Globular domains, Alpha-1, Alpha-2, Beta-1 and Beta-2. The two regions farthest away from the membrane are alpha-1 and beta-1. The two proteins link without Covalent Bonds. The MHC Class II protein mainly presents peptides, which have been digested from external sources. MHC Class II is normally only expressed by Antigen Presenting Cells (APC) which digest foreign protein. Within the RER the alpha and beta proteins of the molecule, associate with each other, while a third protein called the "invariant chain," is necessary for stabilizing the complex, without it, they will not associate. The MHC-invariant complex is then passed from the RER, into and out of, the Golgi body. It fuses with an Endocytic compartment, where an external protein has been sampled and degraded.

Cyclophilin-D is a member of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and speeds up the protein folding. Cyclophilin-D possess PPIase activity and binds to the immunosuppressant cyclosporin-A. Cyclophilin-D is very well known that its overexpression suppresses the apoptosis in cancer cell. Cyclophilin-D suppresses apoptotic cell death by the use of mitochondrial hexokinase-2 dependent mechanism in cancer cells.

Neuroblastoma suppressor of tumorigenicity 1 (NBL1) is a part of the evolutionarily conserved CAN (Cerberus and DAN) family of proteins, which contain a domain resembling the CTCK (C-terminal cystine knot-like) motif found in several signaling molecules. NBL1 is a is a tumor suppressor of neuroblastoma and takes part in preventing cells from entering the final stage (G1/S) of the transformation process. NBL1 is produced in small neurons of the dorsal root ganglion. The expression of NBL1 is triggered by MATH-1.

HSPH1 analysis is used as an indicator and as a diagnostic aid in problematic lesions. HSPH1 chaperones the responses to endoplasmic reticulum (ER) stress during its interactions with GRP78 and GSK3, and without HSP105 cell death following ER stress proceeds by a non-caspase-3-dependent process. HSPH1 is highly expressed in a variety of human tumors. HSPH1 is a mammalian member of the HSP105/110 family, a diverged subgroup of the HSP70 family. HSP105 has 2 isoforms, alpha and beta. Hsp105a associates with Hsp70/Hsc70 as complexes in vivo and regulates the chaperone activity of Hsp70/Hsc70 negatively in vitro and in vivo.

SARS Coronavirus is an enveloped virus containing three outer structural proteins, namely the membrane (M), envelope (E), and spike (S) proteins. Spike (S)-glycoprotein of the virus interacts with a cellular receptor and mediates membrane fusion to allow viral entry into susceptible target cells. Accordingly, S-protein plays an important role in virus infection cycle and is the primary target of neutralizing antibodies.
It has recently been shown that SARS is caused by a human coronavirus. Human coronaviruses are the major cause of upper respiratory tract illness in humans, such as the common cold. Coronaviruses are positive-stranded RNA viruses, featuring the largest viral RNA genomes known to date (27-31 kb). The first step in coronavirus infection is binding of the viral spike protein, a 139-kDa protein, to certain receptors on host cells. The spike protein is the main surface antigen of the coronavirus. The most prominent protein in the culture supernatants infected with SARS virus is a 46 kDa nucleocapsid protein. This suggests that the nucleocapsid protein is a major immunogen that may be useful for early diagnostics.

CD-90 plays a role in cell-cell or cell-ligand interactions during synaptogenesis and other events in the brain Thy-1 is the designation for a major cell surface glycoprotein characteristic to T cells,. The Thy-1 glycoproteins are constituents of thymocytes and neurons and probably are involved in cell-cell interactions. Human Thy-1 homolog maps to chromosome 11 because that is where T3D is found, in the mouse T3D and Thy-1 map to chromosome 9 along with certain other loci that are on human 11q.

Kruppel-Like Factor 7 (KLF7) is a part of the Kruppel-like transcriptional regulator family whose members regulate cell proliferation, differentiation and survival and contain 3 C2H2 zinc fingers at the C-terminus that mediate binding to GC-rich sites. KLF7 contributes to the progression of type 2 diabetes by inhibiting insulin expression and secretion in pancreatic beta-cells and also by deregulating adipocytokine secretion in adipocytes.

TBCB is a member of the Microtubules family. Biosynthesis of functional microtubules include the involvement of a number of chaperones, termed Tubulin folding cofactors A (TBCA), B (TBCB), C (TBCC), D (TBCD) and E (TBCE), which operate on folding intermediates downstream of the cytosolic chaperon, known as TCP. The 244 amino acid cytoplasmic protein TBCB has one CAP-Gly domain and is universally expressed. TBCB takes part in the regulation of tubulin heterodimer dissociation and operates as a negative regulator of axonal growth.

MAT2A is an important enzyme in cellular metabolism and catalyzes the formation of S-adenosylmethionine (SAMe) from L-methionine and ATP. MAT2A is expressed in extrahepatic tissues. In liver, MAT2A expression associates with growth, dedifferentiation, and cancer. NF-kappa B and AP-1 are necessary for basal MAT2A expression in HepG2 cells and mediate the increase in MAT2A expression in response to TNF-alpha. Up-regulation of MAT2A provides growth improvement and s-adenosylmethionine and methylthioadenosine thus can block mitogenic signaling in colon cancer cells. Lower expression of both MAT2A and MAT2beta and interfere with leptin signaling in liver cancer cells.

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.

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.

SSU72 is an extremely conserved homologue of yeast Ssu72, a CTD phosphatase and a component of the polyadenylation/termination machinery. SSU72 interacts with TFIIB, Rb and DNAM-1 and operates to catalyze the dephosphorylation of target proteins, and taking part in RNA processing and termination via dephosphorylation of Pol II. SSU72 is found in multiple alternatively spliced isoforms.

CD86 type I membrane protein is a member of the immunoglobulin superfamily which is expressed by antigen-presenting cells, and acts as the ligand for two proteins at the cell surface of T cells, CD28 antigen and cytotoxic T-lymphocyte-associated protein 4. CD86 binding with CD28 protein is a co-stimulatory signal for initiation of the T-cell. CD86 binding with CTLA-4 negatively regulates T-cell activation and diminishes the immune response.

TLR2 belongs to the Toll-like receptor (TLR) family that plays a fundamental role in pathogen recognition and activation of innate immunity. TLRs are highly conserved from Drosophila to humans and share structural and functional similarities. They recognize pathogen-associated molecular patterns (PAMPs) which are expressed on infectious agents, and mediate the production of cytokines necessary for the development of effective immunity. The various TLRs exhibit different patterns of expression. TLR2 is expressed most abundantly in peripheral blood leukocytes, and mediates host response to Gram-positive bacteria and yeast via stimulation of NF-kappaB.

SORD enzyme is part of of the zinc-containing alcohol dehydrogenase family that is broadly expressed in kidney and in the lens eye. SORD enzymatically catalyzes the zinc-dependent interconversion of polyols, such as sorbitol and xylitol, to their respective ketoses.

FADD is an adaptor protein that cooperates with a variety of cell surface receptors and mediates cell apoptotic signals. Using its C-terminal death domain, FADD is recruited by TNFRSF6/Fas-receptor, tumor necrosis factor receptor, TNFRSF25, and TNFSF10/TRAIL-receptor, and consequently it take parts in the death signaling initiated by these receptors. FADD interaction with the receptors reviels the N-terminal effector domain of, which allows it to recruit caspase-8, and thus initiate the cysteine protease cascade. Knockout studies in mice furthermore propose the significance of FADD in premature T cell development. FADD plays a role in survival/proliferation and cell cycle development. FADD also takes part in cellular sublocalization, protein phosphorylation, and inhibitory molecules.

AK3L1 is an affiliate of the adenylate kinase family of enzymes. AK3L1 enzyme is restricted to the mitochondrial matrix. Adenylate kinases-3 regulates the adenine and guanine nucleotide compositions within a cell by means of catalyzing the reversible transfer of phosphate group among these nucleotides. 5 different isozymes of adenylate kinase have been identified in vertebrates. The enzyme expression of various adenylate kinase isozymes is growth regulated and tissue-specific.

APP is a cell surface receptor and transmembrane precursor protein which is cleaved by secretases to form a number of peptides. Some of these peptides are secreted and can bind to the acetyltransferase complex APBB1/TIP60 to promote transcriptional activation, while others form the protein basis of the amyloid plaques found in the brains of patients with Alzheimer disease. Mutations in the APP gene are implicated in autosomal dominant Alzheimer disease and cerebroarterial amyloidosis (cerebral amyloid angiopathy).

IL4 is a pleiotropic cytokine produced by activated T cells. IL4 is a ligand for interleukin 4 receptor. The interleukin 4 receptor also binds to IL13, which may contribute to many overlapping functions of this cytokine and IL13. STAT6, a signal transducer and activator of transcription, has been shown to play a central role in mediating the immune regulatory signal of this cytokine. This gene, IL3, IL5, IL13, and CSF2 form a cytokine gene cluster on chromosome 5q, with this gene particularly close to IL13. IL4, IL13 and IL5 are found to be regulated coordinately by several long-range regulatory elements in an over 120 kilobase range on the chromosome. Two alternatively spliced transcript variants of this gene encoding distinct isoforms have been reported.

CD44 is a cell-surface glycoprotein that plays a role in cell-cell interactions, cell adhesion and migration. CD44 is a receptor for hyaluronic acid and also interacts with other ligands, such as osteopontin, collagens, and matrix metalloproteinases. CD44 participates in a wide variety of cellular functions such as lymphocyte activation, recirculation and homing, hematopoiesis, and tumor metastasis. CD44 and CD49d are putative activity markers and CD44 a potential novel therapeutic target in multiple sclerosis. Increased CD44 antigen is associated with relapses in non-small cell lung cancers.

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