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The La protein is a 47 kDa polypeptide that frequently acts as an autoantigen in systemic lupus erythematosus and Sjogren's syndrome patients. La is involved in various aspects of RNA metabolism, including binding and protecting 3-prime UUU(OH) elements of newly RNA polymerase III - transcribed RNA, processing 5-prime and 3-prime ends of pre-tRNA precursors, acting as an RNA chaperone, and binding viral RNAs linked to hepatitis C virus. It occurs in both the nucleus and the cytoplasm, where it assumes different roles. In the nucleus, La protein facilitates the production of tRNAs, acting as an RNA polymerase III (RNAP III) transcription factor by attaching to the U-rich 3'UTR of nascent transcripts, aiding in their folding and maturation. In the cytoplasm, La protein facilitates the translation of specific mRNAs, acting as a translation factor. As an RNA binding protein (RBP), La protein associates with subsets of mRNAs which contain a 5'-terminal oligopyrimidine (5'TOP) motif known to direct protein synthesis. The binding of La protein to particular classes of RNA molecules regulates their downstream processing, guards them from endonuclease digestion, and organizes their export from the nucleus. La/SS-B appears to be readily disposed to proteolysis, which results in many smaller (42kD, 320, and 270) nevertheless still immunoreactive polypeptides. La/SS-B antigen is strongly conserved across species. Anti-La/SS-B autoantibodies were originally found as precipitating autoantibodies in sera of Sjogren's Syndrome patients and referred to as SjT. Anti-La/SS-B precipitins are most frequently found in Sjogren's Syndrome, Systemic Lupus Erythematosus (SLE) and Subacute Cutaneous Lupus. Also, there seems to be a correlation between anti-La/SS-B and the absence of nephritis in SLE patients.

Ectonucleoside Triphosphate Diphosphohydrolase 3, also known as ENTPD3, which owns a threefold preference for the hydrolysis of ATP over ADP is similar to E-type nucleotidases (NTPases). ENTPD3 is a protein coding gene which contains four apyrase-conserved areas which is characteristic of NTPases.

CBFB beta subunit is a heterodimeric core-binding transcription factor that is part of the PEBP2/CBF transcription factor family which controls a host of genes particulary to hematopoiesis and osteogenesis. CBFB is a non-DNA binding regulatory subunit which increases DNA binding by alpha subunit.

SEPT2 is a GTPase which is mandatory for cytokinesis and related to exocytosis. Septin-2 protein is able to hetero-oligomerize with Septin6, 7 and in addition takes part in the organization of new growth in organisms. SEPT2 is associated with a Tau-based paired helical filament core and contributes to the creation of neurofibrillary tangle as integral constituents of paired helical filaments.

Ciliary Neurotrophic Factor Receptor (CNTFR) is a member of the type I cytokine receptor family and binds to CNTF. The alpha subunit provides the receptor specificity. Sole nucleotide polymorphisms in CNTFR has been associated with variations in muscle strength, in addition to early onset of eating disorders.

A human infecting coronavirus (viral pneumonia) called 2019 novel coronavirus, 2019-nCoV was found in the fish market at the city of Wuhan, Hubei province of China on December 2019.The 2019-nCoV shares an 87% identity to the 2 bat-derived severe acute respiratory syndrome 2018 SARS-CoV-2 located in Zhoushan of eastern China. 2019-nCoV has an analogous receptor-BD-structure to that of 2018 SARS-CoV, even though there is a.a. diversity so thus the 2019-nCoV might bind to ACE2 receptor protein (angiotensin-converting enzyme 2) in humans.While bats are probably the host of 2019-nCoV, researchers suspect that animal from the ocean sold at the seafood market was an intermediate host. RSCU analysis proposes that the 2019-nCoV is a recombinant within the viral spike glycoprotein between the bat coronavirus and an unknown coronavirus.

COP9 signalosome complex subunit 8 isoform 1 (COPS8) is one of the 8 subunits of COP9 signalosome, which is a much conserved protein complex that functions as an imperative regulator in multiple signaling pathways. The structure and function of COP9 signalosome is analogous to that of the 19S regulatory particle of 26S proteasome. COP9 signalosome interacts with SCF-type E3 ubiquitin ligases and acts as a positive regulator of E3 ubiquitin ligases.

Methionine sulfoxide reductase B1 (SEPX1 or MSRB1), is a selenoprotein that contains a selenocysteine (Sec) residue at its active site. The selenocysteine is encoded by the UGA codon that usually signals translation termination. SEPX1 is a member of the methionine sulfoxide reductase B (MsrB) family, and is expressed in an assortment of adult and fetal tissues. MSRs (Methionine sulfoxide reductases) catalyze the reduction of free and protein-bound methionine sulfoxides to corresponding methionines. The oxidation of methionine by ROS creates a diastereomeric mixture of methionine-S-sulfoxide (Met-S-SO) and methionine-R-sulfoxide (Met-R-SO). Two separate enzyme families evolved for reduction of these sulfoxides, with methionine-S-sulfoxide reductase (MsrA) being stereospecific for Met-S-SO and methionine-R-sulfoxide reductase (MsrB) for Met-R-SO.

DIRAS1 is a member of a distinct branch of the functionally diverse Ras superfamily of monomeric GTPases. DIRAS1 demonstrates low GTPase activity and exists mainly in the GTP-bound form. Ras proteins operate as binary molecular switches that control intracellular signaling networks. Ras-regulated signal pathways regulate such processes as actin cytoskeletal integrity, proliferation, differentiation, cell adhesion, apoptosis, and cell migration. Ras and ras-related proteins are frequently deregulated in cancers, leading to increased invasion and metastasis, and decreased apoptosis.

Tumor necrosis factor is a cytokine involved in systemic inflammation and is a member of a group of cytokines that all stimulate the acute phase reaction. TNF is mainly secreted by macrophages.
TNF causes apoptotic cell death, cellular proliferation, differentiation, inflammation, tumorigenesis and viral replication, TNF is also involved in lipid metabolism, and coagulation. TNF's primary role is in the regulation of immune cells.
Dysregulation and, in particular, overproduction of TNF have been implicated in a variety of human diseases- autoimmune diseases, insulin resistance, and cancer.

KLK7 catalyzes the degradation of intercellular cohesive structures in the cornified layer of the skin in the continuous shedding of cells from the skin surface. Specific for amino acid residues with aromatic side chains in the P1 position. KLK7 cleaves insulin B chain at ''6-Leu- -Cys-7'', ''16-Tyr- -Leu-17'', ''25-Phe- -Tyr-26'' and ''26-Tyr--Thr-27''. KLK7 is involved in the activation of precursors to inflammatory cytokines.

SARS Coronavirus is an enveloped virus containing 3 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 takes part in virus infection cycle and is the primary target of neutralizing antibodies.

Yersinia enterocolitica is a Gram-negative bacillus-shaped bacterium, which is a member of the Enterobacteriaceae family. Y.Enterocolitica is motile at temperatures between 22-29°C, however becomes non-motile at normal human body temperature. Y. Enterocolitica infection causes the yersiniosis disease, which is an animal-borne disease occurring in humans, as well as in a various groups of animals such as cattle, deer, pigs, and birds. Yersinia enterocolitica is a heterogeneous group of strains, which are conventionally classified by bio-typing into six bio-groups on the basis of phenotypic characteristics, and by serotyping into more than 57 “O” serogroups, on the basis of their O (lipopolysaccharide or LPS) surface antigen. Five of the six biogroups (1B and 2–5) are considered as pathogens. Nevertheless, only a few of these serogroups have been linked with disease in either humans or animals. Strains which belong to serogroups O:3 (biogroup 4), O:5,27 (biogroups 2 and 3), O:8 (biogroup 1B), and O:9 (biogroup 2) are most frequently isolated worldwide from human samples. Still, the main Y. enterocolitica serogroup in many European countries is serogroup O:3 followed by O:9, whereas the serogroup O:8 is mostly detected in the United States.

Retinoblastoma (RB) is an embryonic malignant neoplasm of retinal origin. It almost always presents in early childhood and is often bilateral. Spontaneous regression ('cure') occurs in some cases. Retinoblastoma acts as a regulator of other genes and forms a complex with adenovirus e1a and with sv40 large t antigen. Retinoblastoma acts as a tumor suppressor and modulats functionally certain cellular proteins with which t and e1a compete for pocket binding. Retinoblastoma is potent inhibitor of e2f-mediated trans-activation, recruits and targets histone methyltransferase suv39h1 leading to epigenetic transcriptional repression, inhibits the intrinsic kinase activity of taf1.

DDX39A which is a part of the DEAD box protein family is characterized by the conserved motif Asp-Glu-Ala-Asp. This pattern is implicated in a various cellular processes involving alteration of RNA secondary structure, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Several members of the DEAD box protein family are taking part in embryogenesis, spermatogenesis, and cellular growth and division.

Hepatitis A Virus Cellular Receptor 2 (HAVCR2) is a member of the immunoglobulin superfamily. HACVR2 controls macrophage activation. HACVR2 inhibits T-helper type 1 lymphocyte (Th1)-mediated auto- and alloimmune responses and stimulates immunological tolerance.

Caspase 3 Apoptosis-Related Cysteine Peptidase (CASP3) belongs to the cysteine-aspartic acid protease (caspase) family. Sequential activation of caspases plays a key role in the execution-phase of cell apoptosis. Caspases exist as inactive proenzymes which undergo proteolytic processing at conserved aspartic residues to generate 2 subunits, large and small, that dimerize to create the active enzyme. CASP3 protein cleaves and activates caspases 6, 7 and 9, and the protein itself is processed by caspases 8, 9 and 10. CASP3 is the leading caspase involved in the cleavage of amyloid-beta 4A precursor protein, which is linked with neuronal death in Alzheimer's disease. In addition, CASP3 is involved in the cleavage of huntingtin. CASP3 also cleaves and activates sterol regulatory element binding proteins (SREBPs) between the basic helix-loop-helix leucine zipper domain and the membrane attachment domain. CASP3 initiates cell adhesion in sympathetic neurons through RET cleavage.

The protein encoded by this gene is a member of the TNF-receptor superfamily. This receptor contributes to the clonal expansion, survival, and development of T cells. It can also induce proliferation in peripheral monocytes, enhance T cell apoptosis induced by TCR/CD3 triggered activation, and regulate CD28 co-stimulation to promote Th1 cell responses. The expression of this receptor is induced by lymphocyte activation. TRAF adaptor proteins have been shown to bind to this receptor and transduce the signals leading to activation of NF-kappaB.

Synaptobrevin-2 or VAMP2 is a protein that has a proline-rich N-terminal part, highly conserved hydrophilic domain, a transmembrane anchor and a C-terminal.VAMP2 found in the transmembrane region of the cell, in the cytoplasmic surface of the synaptic vesicle. The protein is mainly found in the Langerhans islets in the pancreas and glomerular cells in the kidney. A SNARE complex is created within the protein’s N-terminal domain and the target membrane-associated T.

VZV is closely related to the herpes simplex viruses(HSV), sharing much genomehomology. The known envelope glycoproteins (gB, gC, gE, gH, gI, gK, gL) correspond with those in HSV, however there is no equivalent of HSV gD. VZV virons are spherical and 150-200 nm in diameter. Their lipidenvelope encloses the nucleocapsid of 162 capsomeres arranged in a hexagonalform. Its DNAis a single, linear, double-stranded molecule, 125,000 nt long. The virus is very susceptible to disinfectants, notably sodium hypochlorite. Within the body it can be treated by a number of drugs and therapeutic agents including aciclovir, zoster-immune globulin(ZIG), and vidarabine.

Beta 2 microglobulin is an 11 kDa protein associated with the outer membrane of many cells including lymphocytes. It is the small subunit of the MHC class I molecule. Association with beta 2-microglobulin is generally required for the transport of class I heavy chains from the endoplasmic reticulum to the cell surface. Beta 2 microglobulin associates with class I-like molecules such as CD1 and Qa as well as with the alpha chain of MHC class I molecules. Very limited amounts of MHC class I molecules can be found on the surface in the absence of Beta 2 microglobulin. CD8 T cells cannot develop in the absence of MHC class I.
Beta 2-microglobulin is present in small amounts in serum, csf, and urine of normal people, and to a much greater degree in the urine and plasma of patients with tubular proteinaemia, renal failure, or kidney transplants. Human Beta 2 microglobulin levels can rise either because its rate of synthesis has increased (e.g. in AIDS, malignant monoclonal plasma cell dyscrasia, solid tumors and autoimmune disease) or because of impaired renal filtration (e.g. due to renal insufficiency, graft rejection or nephrotoxicity induced by post-transplantation immunosuppressive therapy). Beta-2 microglobulin levels might also be elevated in multiple myeloma and lymphoma cases. Dialysis-related amyloidosis develops after a long-term hemodialysis, it can aggregate into amyloid fibers that deposit in joint spaces.

IL-9 is a factor which is thought to be a regulator of hematopoiesis. It has been shown to enhance the growth of human mast cells and megakaryoblastic leukemic cells as well as murine helper t-cell clones. IL-9 is a glycoprotein with a molecular weight of 32-39 that is derived from T-cells, and maps to human chromosome 5.

Streptavidin is a tetrameric protein secreted by Streptomyces avidinii which binds firmly to biotin. Streptavidin is widely used in molecular biology through its unique high affinity for the vitamin biotin. The dissociation constant (Kd) of the biotin-streptavidin complex is about ~10-15 mol/L. The strong affinity recognition of biotin and biotinylated molecules has made streptavidin one of the most important components in diagnostics and laboratory kits. The streptavidin/biotin system has one of the biggest free energies of association of yet observed for noncovalent binding of a protein and small ligand in aqueous solution (K_assoc = 10**14). The complexes are also extremely stable over a wide range of temperature and pH.