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Members of the IFN regulatory factor (IRF) family regulate gene expression critical to immune response, hemopoiesis, and proliferation. IRF-3 is a member of the IRF family, and is distinct from other family members. Its transcriptional activity is regulated solely by posttranslational modifications. It plays a crucial role in activation of innate immunity and inflammation in response to viral infection. IRF-3 mediates IFN-stimulated response element (isre) promoter activation. Functions as a molecular switch for antiviral activity. Dsrna generated during the course of an viral infection leads to IRF3 phosphorylation on the c-terminal serine/threonine cluster. This induces a conformational change, leading to its dimerization, nuclear localization and association with creb binding protein (crebbp) to form dsrna-activated factor 1 (draf1), a complex which activates the transcription of genes under the control of isre. The complex binds to the ie and prdiii regions on the ifn-alpha and ifn-beta promoters respectively. IRF-3 does not have any transcription activation domains.

The human Lymphocyte Antigen 6 Complex Locus G6F (LY6G6F) protein is a type I transmembrane protein belonging to the immunoglobin (Ig) superfamily, which contains cell-surface proteins involved in the immune system and cellular recognition. The LY6G6F protein has a role in the downstream signal transduction pathways involving GRB2 and GRB7.

Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes. All VEGF-receptors have seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular split tyrosine kinase domain. VEGFR-2 has a lower affinity for VEGF than the Flt-1 receptor, but a higher signaling activity. Mitogenic activity in endothelial cells is mainly mediated by VEGFR-2 leading to their proliferation.
Differential splicing of the flt-1 gene leads to the formation of a secreted, soluble variant of VEGFR-1 (sVEGFR-1). No naturally occuring, secreted forms of VEGFR-2 have so far been reported. The binding of VEGF165 to VEGFR-2 is dependent on heparin.

The IL1RL1 gene is a member of the IL-1 receptor family, encoding a transmembrane protein with a structure similar to IL-1R1. IL1RL1 is a receptor for interleukin-33, its stimulation recruits MYD88, IRAK1, IRAK4, and TRAF6, followed by phosphorylation of MAPK3/ERK1 and/or MAPK1/ERK2, MAPK14, and MAPK8. IL1RL1 may possibly be involved in helper T-cell function. IL1RL1 is highly expressed in kidney, lung, placenta, stomach, skeletal muscle, colon and small intestine.A soluble form of the IL1RL1 is produced from the same gene by alternative splicing and was shown to be expressed in several cell types including fibroblasts and mast cells. Soluble IL1RL1 also acts as a negative regulator of Th2 cytokine production and high levels have been reported in several disease states and conditions including asthma, sepsis and myocardial infarction.Analysis of the similar gene in mouse suggested that the IL1RL1 receptor can be induced by proinflammatory stimuli, and may be involved in the function of helper T cells.

Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.

Complement C1q Tumor Necrosis Factor-Related Protein 5 (C1QTNF5) encodes a short-chain collagen which is expressed mainly in sub-retinal pigment epithelium, ciliary epithelium and adipose tissue. C1QTNF5 is increased in mtDNA-depleted myocytes and stimulates the phosphorylation of AMP activated protein kinase. C1QTNF5 takespart in the adhesion of the retinal pigment epithelium (RPE) to the Bruch Membrane. Mutations in C1QTNF5 have been associated with late-onset retinal degeneration.

FKBP2 is part of the immunophilin protein family, which takes part in immunoregulation and basic cellular processes involving protein folding and trafficking. FKBP2 is a cis-trans prolyl isomerase that binds the immunosuppressants FK506 and rapamycin. FKBP2 functions as an ER chaperone and as a component of membrane cytoskeletal scaffolds.

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.

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 extracellular immunoglobulin domains (2D or 3D) and by whether they have a long (L) or short (S) cytoplasmic domain. KIR proteins with the long cytoplasmic domain transduce inhibitory signals upon ligand binding via an immune tyrosine-based inhibitory motif (ITIM). Whereas KIR proteins with the short cytoplasmic domain lack the ITIM motif and instead associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals.
KIR2DL1 is an inhibitory Killer Cell Ig-like Receptor (KIR, previously called p58 KIR, p58.1, cl-42, NKAT1, or KIR-K6), which recognizes class I MHC molecules (HLA-Cw2, -Cw4, -Cw5, and Cw6). The extracellular domain of KIR2DL1 was over expressed as insoluble protein aggregates (inclusion bodies).

TNFRSF13B (TACI) is a transmembrane receptor protein found predominantly on the surface of B cells (a significant part of the immune system). TACI was at first discovered owing to its ability to interact with calcium-modulator and cyclophilin ligand (CAML). Later on, it was found that TACI plays a key role in humoral immunity by interacting with two members of the TNF family. Also, TACI controls T cell-independent B cell antibody responses, isotype switching, and B cell homeostasis.

Signal-Regulatory Protein Gamma (SIRPG) belongs to the signal-regulatory protein (SIRP) family whose members are receptor-type transmembrane glycoproteins which negatively regulate the receptor tyrosine kinase-coupled signaling processes. SIRPG is also a part of the immunoglobulin superfamily.

Ferritin is a fairly large, iron-storage heteropolymeric protein composed of 2 subunit types, light Ferritin & heavy Ferritin polypeptides, which is expressed in most kinds of cells and co-assemble in different proportion in a tissue-specific manner. Ferritin is composed of 24 self-assembled polypeptide subunits of the heavy and light ferritin chains and is characterized by the capacity to remove Fe from solution in the presence of oxygen.
Ferritin light polypeptide protein is the main intracellular iron storage protein in prokaryotes and eukaryotes. Variation in ferritin subunit composition influence the rates of iron uptake and release in various tissues. A key function of ferritin is the storage of iron in a soluble and nontoxic state. Defects in this light chain ferritin gene are associated with several neurodegenerative diseases and hyper ferrit anemia-cataract syndrome.
Ferritin stores iron in a soluble, nontoxic, readily accessible form. Ferritin is needed for iron homeostasis. Iron is taken up in the ferrous form and deposited as ferric hydroxides after it has been oxidized.

Macrophage Scavenger Receptor 1, also known as MSR1 is a member of the class A macrophage scavenger receptors, which comprises three different types 1, 2 and 3 generated by alternative splicing. Furthermore, these receptors or isoforms are macrophage-specific trimeric integral membrane glycoproteins and have been implicated in many macrophage-associated physiological as well as pathological processes which include atherosclerosis, Alzheimer's disease, and host defense.

Interleukin-1 ra is a member of the interleukin 1 cytokine family. This protein inhibits the activities of interleukin 1, alpha (IL1A) and interleukin 1, beta (IL1B), and modulates a variety of interleukin 1 related immune and inflammatory responses. This gene and five other closely related cytokine genes form a gene cluster spanning approximately 400 kb on chromosome 2. A polymorphism of this gene is reported to be associated with increased risk of osteoporotic fractures and gastric cancer. Four alternatively spliced transcript variants encoding distinct isoforms have been reported.

IL3RA, also known as Interleukin 3 Receptor Subunit Alpha, is a single-pass type 1 membrane protein which is a member of the type 1 cytokine receptor family as well as type 5 subfamily. IL3RA is a pleiotropic cytokine which is produced mainly by activated T cells or mast cells. Moreover, the specific alpha subunit of the interleukin 3 receptor is strongly expressed in a variety of leukemic blasts as well as leukemic stem cells and appears to be a great target for the therapy of leukemias.

PDGFRa is a cell surface tyrosine kinase receptor for PDGF family members. PDGFRa binds to both A and B subunits of PDGF. It is known that PDGFRa is vital for kidney development since mice heterozygous for the receptor display defective kidney phenotypes.

Thymic Stromal Lymphopoietin Receptor (TSLPR) is a member of the type I cytokine receptor family. TSLPR alongside the interleukin 7 receptor (IL7R) activate STAT3, STAT5, and JAK2 pathways, which is regulated processes such as cell proliferation and development of the hematopoietic system. Two transcript variants encoding dissimilar isoforms have been found for this gene. TSLPR is expressed in heart, skeletal muscle, kidney and adult and fetal liver.

CD79B is a 36 kDa trans membrane glycoprotein belonging to the immunoglobulin superfamily. Heterodimers of CD79A and CD79B connect with a membrane attached immunoglobulin on the B cell surface to create the B cell antigen receptor complex (BCR). CD79A and CD79B are essential for BCR-mediated signaling and subsequently for the development and activation of B lineage cells.

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.

TNFR2 belongs to the TNF-receptor superfamily. TNFR2 is receptor with high affinity for TNFSF2/TNF-alpha and approximately 5-fold lower affinity for homotrimeric TNFSF1/lymphotoxin-alpha. TNFR2 mediates the majority of the metabolic effects of TNF-alpha. In addition, knockout studies in mice propose a role for TNFR2 in protecting neurons from apoptosis by stimulating antioxidative pathways. TNFR2 expression might have a significant role in the angiogenesis, tumor cell proliferation and metastasis of Invasive micropapillary carcinoma of the breast.
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. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women. TNFR2 and TNFR1 form a heterocomplex which mediates the recruitment of 2 anti-apoptotic proteins, c-IAP1 and c-IAP2, which possess E3 ubiquitin ligase activity. IAPs’ function in TNF-receptor signaling is unknown; nevertheless, c-IAP1 is believed to potentiate TNF-induced apoptosis by the ubiquitination and degradation of TNF-receptor-associated factor 2, which mediates anti-apoptotic signals. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.

DiGeorge syndrome critical region 6-like protein (DGCR6L) shares homology with the Drosophila gonadal protein, it is expressed in gonadal tissues and germ cells, and with the human laminin gamma-1 chain which functions in cell attachment and migration. DGCR6L is located in a region of chromosome 22 involved in the DiGeorge syndrome, one aspect of a wider collection of anomalies referred to as the CATCH 22 syndrome. Moreover, it is one of two functional genes encoding nearly identical proteins which have analogous expression patterns.

CD3-gamma polypeptide is encoded by CD3 Gamma (CD3G) which together with CD3-epsilon, -delta and -zeta, and the T-cell receptor alpha/beta and gamma/delta heterodimers, configures the T-cell receptor-CD3 complex. The T-cell receptor-CD3 complex takes part in coupling antigen recognition to numerous intracellular signal-transduction pathways. The genes encoding the epsilon, gamma and delta polypeptides are located in the same cluster on chromosome 11. Deficiencies in this gene are associated with T cell immunodeficiency.

Factor B is a protein, build from a single chain that circulates in the blood. Complement factor D cleaves and activates factor B, thus creating a catalytic subunit Bb and noncatalytic chain Ba. Subunit Bb is a serine protease that can bind to C3b and forms alternative pathway C3 convertase. Subunit Ba acts as an inhibitor for proliferation of lymphocytes, when Bb is part of the lymphocytes’ proliferation. The gene that codes for this protein is located on chromosome six.