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SPRY Domain-Containing SOCS Cox Protein 2 (SPSB2) belongs to a suppressor of cytokine signaling (SOCS) family, and is a member of the subfamily of proteins containing a central SPRY (repeats in splA and RyR) domain and a C-terminal SOCS box. SPSB2 is present in a gene-rich cluster on chromosome 12p13 in the vicinity of the CD4 antigen and triosephosphate isomerase genes. SPSB2 is apparent substrate recognition component of a SCF-like ECS (Elongin BC-CUL2/5-SOCS-box protein) E3 ubiquitin-protein ligase complex that mediates the ubiquitination and ensuing proteasomal degradation of target proteins.

CALR is a multifunctional protein that acts as a main Ca(2+)-binding (storage) protein in the lumen of the endoplasmic reticulum. Calreticulin is localized in the nucleus, and participates in transcription regulation. Calreticulin binds to the synthetic peptide KLGFFKR, which is nearly identical to an amino acid sequence in the DNA-binding domain of the superfamily of nuclear receptors. CALR binds to antibodies in specific sera of systemic lupus and Sjogren patients which have anti-Ro/SSA antibodies, it is well conserved among species, and it is positioned in the endoplasmic and sarcoplasmic reticulum where it binds calcium. The amino terminus of CALR interacts with the DNA-binding domain of the glucocorticoid receptor and prevents the receptor from binding to its specific glucocorticoid response element. CALR reduces the binding of androgen receptor to its hormone-responsive DNA element and inhibits androgen receptor and retinoic acid receptor transcriptional activities in vivo, as well as retinoic acid-induced neuronal differentiation. Therefore, CALR acts as a significant modulator of the regulation of gene transcription by nuclear hormone receptors.

RAC3 belongs to the Rac subfamily of the Rho small G proteins. RAC3 is a small (approximately 21kDa) monomeric GTP-binding protein, which is an important component of intracellular signaling pathway, including the control of cell growth, cytoskeletal reorganization, and the activation of protein kinases.

RASSF1A protein is a potential tumor suppressor like the RAS effector proteins. Presence or absence expression of this gene has been related with the pathogenesis of a variety of cancers, which suggests the tumor suppressor function of this RASSF1A gene. The inactivation of RASSF1A was found to be associated with the hypermethylation of its CpG-island promoter region. RASSF1A required for death receptor-dependent apoptosis.

HCV is a small 50nm, enveloped, single-stranded, positive sense RNAvirus in the family Flaviviridae.
HCV has a high rate of replication with approximately one trillion particles produced each day in an infected individual. Due to lack of proofreading by the HCV RNA polymerase, the HCV has an exceptionally high mutation rate, a factor that may help it elude the host's immune response. Hepatitis C virus is classified into six genotypes(1-6) with several subtypes within each genotype. The preponderance and distribution of HCV genotypes varies globally. Genotype is clinically important in determining potential response to interferon-based therapy and the required duration of such therapy. Genotypes 1 and 4 are less responsive to interferon-based treatment than are the other genotypes (2, 3, 5 and 6).

Hepatitis E virus (HEV), the major etiologic agent of enterically transmitted non-A, non-B hepatitis worldwide, is a spherical, non-enveloped, single stranded RNA virus that is approximately 32 to 34 nm in diameter. HEV belongs to a genus of HEV-like viruses (unassigned genus). HEV has a single-stranded polyadenylated RNA genome of approximately 8 kb. Based on its physicochemical properties it is presumed to be a calici-like virus.

Human immunodeficiency virus (HIV) is a retrovirusthat can lead to a condition in which the immune systembegins to fail, leading to opportunistic infections. HIV primarily infects vital cells in the humanimmune systemsuch as helper T cells(specifically CD4+ T cells), macrophagesand dendritic cells. HIV infection leads to low levels of CD4+ T cells through three main mechanisms: firstly, direct viral killing of infected cells; secondly, increased rates of apoptosisin infected cells; and thirdly, killing of infected CD4+ T cells by CD8 cytotoxic lymphocytesthat recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunityis lost, and the body becomes progressively more susceptible to opportunistic infections. HIV was classified as a member of the genus Lentivirus, part of the family of Retroviridae. Lentiviruses have many common morphologies and biological properties. Many species are infected by lentiviruses, which are characteristically responsible for long-duration illnesses with a long incubation period. Lentiviruses are transmitted as single-stranded, positive-sense, enveloped RNA viruses. Upon entry of the target cell, the viral RNA genomeis converted to double-stranded DNAby a virally encoded reverse transcriptasethat is present in the virus particle. This viral DNA is then integrated into the cellular DNA by a virally encoded integraseso that the genome can be transcribed. Once the virus has infected the cell, two pathways are possible: either the virus becomes latentand the infected cell continues to function, or the virus becomes active and replicates, and a large number of virus particles are liberated that can then infect other cells.

4-1BBR is a member of the TNF-receptor superfamily. 4-1BB receptor contributes to the clonal expansion, survival, and development of T cells.4-1BBRcan 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.

Mouse S100A15 is a protein of 104 amino acids with an expected molecular weight of 12,870 Dalton having 2 EF-hand calcium binding sites. The S100A15 expression is upregulated in cultured keratinocytes stimulated to differentiate by calcium or phorbol esters. S100A15 is expressed in the skin and keratinocytes.

Adiponectin is a recently discovered 244 amino acid protein, the product of the apM1 gene, which is physiologically active and specifically and highly expressed in adipose cells (Adipokine). The protein belongs to the soluble defense collagen super family; it has a collagen-like domain structurally homologous with collagen VIII and X and complement factor C1q-like globular domain. APM-1 forms homotrimers, which are the building blocks for higher order complexes found circulating in serum.

Small nuclear ribonucleoprotein complexes (abbreviated as U-snRNP) are essential for splicing of precursor mRNA molecules. U1-snRNP is the most abundant RNP particle in the nucleus and consists of one small uridylate-rich RNA (U1 RNA) complexed with several proteins: the three 68/70 kDa, A, C polypeptides are unique to the U1-snRNP particle, whereas 7 so-called Sm proteins (B/B', D1, D2, D3, E, F, G) form a core subparticle that is common to all U-snRNP complexes.
Both the U1-specific proteins and the Sm core particle are targets of autoantibodies which classically have been called the RNP and RNP-Sm specificities, respectively. A clean diagnostic distinction of these specificities has been complicated by the biochemical difficulties of producing clean subparticle fractions from native sources. The use of single recombinant proteins as antigenic targets guarantees a much higher sensitivity and specificity and is the only way to determine RNP antibodies sensu stricto without the disturbing influence of Sm antigens; also with single U1 proteins antibodies will be detected which can be missed because of steric hindrance when using the RNP-Sm complex in an assay.
Autoantibodies to U1-snRNP are present in 95% of patients with Mixed Connective Tissue Disease (MCTD) and 30% of patients with SLE. Antibodies against the 68/70 kDa protein are known to have a high clinical significance in MCTD patients. The 68/70 kDa nomenclature of this protein refers to the fact that different splice variants of the protein are found in human cells.

AURKA (Aurora Kinase A) belongs to the mitotic serine/threonine kinases family. AURKA is a cell cycle-regulated kinase which may be involved in microtubule formation and/or stabilization at the spindle pole during chromosome segregation. AURKA is found at the centrosome in interphase cells and at the spindle poles in mitosis. Since the AURKA expression is cell-cycle regulated, it is low in G1/S, it accumulates during G2/M, and it decreases rapidly after. AURKA is involved in important processes during mitosis and meiosis whose proper function is essential for healthy cell proliferation. In addition, AURKA plays an essential role in tumourigenesis and is overexpressed in various types of cancers. AURKA is strongly expressed in the testis, colon, ovarian, prostate, neuroblastoma, breast and cervical cancer cell lines and weakly in skeletal muscle, thymus and spleen. AURKA interacts with its substrates BORA and ARHGEF2, as well as with TACC1 and CPEB1.
Defects in the AURKA gene cause numerical centrosome aberrations including aneuploidy. AURKA overexpression has been linked to chromosomal instability in colorectal cancer. AURKA expression may have a prognostic significance in ovarian carcinoma.

Procalcitonin is a peptide hormone mainly produced by the C cells of the thyroid and certain endocrine cells of the lung. Under normal expression conditions, procalcitonin is immediately cleaved into three specific fragments, an N terminal residue, calcitonin and katacalcin. Levels of unprocessed procalcitonin rise significantly after bacterial infection, trauma or shock.

RAB14 belongs to the RAB protein family, low molecular mass monomeric GTPases which is found on the cytoplasmic surfaces of distinct membrane bound organelles. RAB14 has a role in vesicular trafficking and neurotransmitter release throughout the body and is expressed at high levels in brain, lung, kidney, spleen and thymus. In addition, RAB14 takes part in the biosynthetic/recycling pathway between the Golgi and endosomal compartments.

MS4A1 is an activated-glycosylated phosphoprotein expressed on the surface of all B-cells. The expression begins at the pro-B phase and until maturity the concentration increases in order to allow optimal B-cell immune response, specifically against T-independent antigens. MS4A1 takes part in the microenvironmental interactions of B cells and also in the regulation of B-cell activation and proliferation. MS4A1 also plays a role as a calcium channel in the cell membrane.

Signal-Regulatory Protein Alpha, SIRPA belongs to the signal-regulatory-protein (SIRP) family, as well as the immunoglobulin super family. The members of the SIRP family are receptor-type transmembrane glycoproteins which are involved in the negative regulation of receptor tyrosine kinase-coupled signaling processes.
SIRPA can be phosphorylated by tyrosine kinases. The phospho-tyrosine residues of this PTP have been shown to recruit SH2 domain containing tyrosine phosphatases (PTP), and perform as substrates of PTPs. SIRPA take part in signal transduction mediated by a variety of growth factor receptors. CD47 has been shown to be a ligand for SIRPA.

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.

Fc Fragment Of IgA Receptor, also known as FCAR, is part of the multichain immune recognition receptor family which is the most abundant immunoglobulin in mucosal areas however it is only the second most common antibody isotype in serum. FCAR participates in both pro-and anti-inflammatory responses depending on the state of IgA bound. FCAR is also a vital Fc receptor for neutrophil killing of tumor cells. Once FCAR expressing neutrophils interact with IgA-opsonized tumor cells, the neutrophils not only show antibody-dependent cell-mediated cytotoxicity, but also release the cytokines TNF-α and IL-1β which cause increased neutrophil migration to the site.

JSRP1 takes part in excitation-contraction connection at the sarcoplasmic reticulum. JSRP1 is able to cooperate with CACNA1S, CACNB1 and calsequestrin to assist in regulating calcium influx and efflux in skeletal muscle.

Ro 60 kDa autoantigen is an RNA-binding protein that binds to several small cytoplasmic RNA molecules known as Y RNAs. SSA2 may stabilize these RNAs from degradation. Sera taken from patients with Systemic Lupus Erythematosus (SLE) often contains antibodies that react with the normal cellular SSA2 protein as if this antigen was foreign.

Ribosomal Protein S19, also known as RPS19, is a part of the S19E family of ribosomal proteins. RPS19 is located in the cytoplasm and required for pre-rRNA processing and maturation of 40S ribosomal subunits. Mutations in RPS19 trigger Diamond-Blackfan anemia, a constitutional erythroblastopenia characterized by absent or decreased erythroid precursors, in a subset of patients.

RPS24 is a member of the S24E family of ribosomal proteins. RPS24 is situated in the cytoplasm. Numerous transcript variations encoding different isoforms were identified for this gene. There are multiple processed pseudogenes of this gene distributed all over the genome just like other genes encoding ribosomal proteins. Alterations in RPS24 cause Diamond-Blackfan anemia.

S100A1 is a member of the S100 family of calcium binding proteins with EF-hand type Ca+2 binding motive. S100A1 (Calcium Binding Protein A1) is involved in the activation of sarcoplasmatic calcium release and the regulation of intermediate filament polymerization. S100A1 may function in stimulation of Ca2+-induced Ca2+ release, inhibition of microtubule assembly, and inhibition of protein kinase C-mediated phosphorylation. Reduced expression of S100A1 has been implicated in cardiomyopathies.
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.

S100A8 is a part of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a broad range of cells, and participate in the regulation of cellular processes such as cell cycle progression and differentiation. S100A8 plays a role in the inhibition of casein kinase and as a cytokine. S100A8 altered expression is related with cystic fibrosis disease. S100A8 is a calcium-binding protein that has antimicrobial activity against bacteria and fungi.S100A8 is crucial for resistance towards invasion by pathogenic bacteria. S100A8 up-regulates transcription of genes that are under the control of NF-kappa-B. S100A8 plays a role in the development of endotoxic shock in response to bacterial lipopolysaccharide. S100A8 endorses tubulin polymerization and promotes phagocyte migration and infiltration of granulocytes at sites of wounding. S100A8 takes part as a pro-inflammatory mediator in acute and chronic inflammation and up-regulates the release of IL8 and cell-surface expression of ICAM1.