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The cytokine Macrophage migration inhibitory factor (MIF) has been identified to be secreted by the pituitary gland and the monocyte/macrophage and to play an important role in endotoxic shock. MIF has the unique property of being released from macrophages and T cells in response to physiological concentrations of glucocorticoids. The secretion of MIF is tightly regulated and decreases at high, anti-inflammatory steroid concentration.

Chemokine (C-X-C motif) ligand 10 (CXCL10) is a small cytokine belonging to the CXC chemokine family. CXCL10 is secreted by several cell types. These cell types include monocytes, endothelial cells and fibroblasts. CXCL10 has been attributed to several roles, such as chemoattraction for monocytes and T cells, promotion of T cell adhesion to endothelial cells, antitumor activity, and inhibition of bone marrow colony formation and angiogenesis. The gene for CXCL10 is located on human chromosome 4 in a cluster among several other CXC chemokines. This chemokine elicits its effects by binding to the cell surface chemokine receptor CXCR3. The three-dimensional crystal structure of this chemokine has been determined under 3 different conditions to a resolution of up to 1.92A.

Canopy 3 homolog (CNPY3) is a 271 a.aToll-like receptor specific co-chaperone for HSP90B1. CNPY3 is necessitated for proper TLR folding, excluding that of TLR3, and so controls TLR exit from the endoplasmic reticulum. Therefore, CNPY3i s required for both innate and adaptive immune responses.

Protein MIS12 Belongs to the mis12 family. MIS12 is an element of the MIS12 complex, which is necessary for kinetochore formation during mitosis and normal chromosome alignment and segregation. The MIS12 complex which comprised of MIS12,DSN1 , NSL1 and PMF-1. MIS12 is section of a network of complexes that supply microtubule attachment and generates pulling forces from depolymerization.

Syndecan 2 (SDC2) is a conserved family of heparan- and chondroitin-sulfate carrying transmembrane protein. Syndecan 2 is a cell membrane proteoglycan which modulates the activity and dynamics of some growth factor receptors and integrins. SDC2 is expressed in HSCs (hepatic stellate cells), a key cell type involved in matrix deposition in liver fibrotic disorders. SDC2 is implicated in the formation of specialized membrane domains and serves as a direct link between the extracellular environment and the organization of the cortical cytoplasm.

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.

Signal recognition particle 19kDa protein (SRP19) is a member of the SRP19 family. SRP19 binds directly to 7S RNA and mediates binding of the 54 kDa subunit of the SRP.

Small VCP/p97-interacting protein (SVIP) is involved in various cellular processes, including membrane fusion and ubiquitin-dependent protein degradation. SVIP functions as an inhibitor of the endoplasmic reticulum (ER)-associated degradation (ERAD) pathway. On the other hand, SVIP overexpression increased the levels of p62 protein and enhanced starvation-activated autophagy as well as stimulated sequestration of polyubiquitinated proteins and p62 in autophagosomes.

RING1- and YY1-binding protein (RYBP) belongs to the polycomb group (PcG). RYBP interacts with MDM2 and decreases MDM2-mediated p53 ubiquitination, which leads to stabilization of p53 and an increase in p53 activity. RYBP causes cell-cycle arrest and is involved in the p53 response to DNA damage. RYBP interacts with RING1, YY1, Caspase 10, E2F3, E2F2, Mdm2, Abl gene and CBX2. RYBP inhibits ubiquitination and subsequent degradation of TP53, and thus has a role in regulating transcription of TP53 target genes. RYBP may also be involved in the regulation of the transcription as a repressor of the transcriptional activity of E4TF1. RYBP may bind to DNA, and promote apoptosis.

Actin-related protein 2/3 complex subunit 3 (ARPC3) which Belongs to the ARPC3 family is one of 7 subunits of the human Arp2/3 protein complex. The Arp2/3 complex is involved in regulation of actin polymerization and together with an activating nucleation-promoting factor (NPF) mediates the formation of branched actin networks. ARPC3 which is localized to the cytoplasm and cytoskeleton, interacts with p20-ARC and takes part in the structural integrity of the protein complex.

RGS16 is part of the ''regulator of G protein signaling'' family. RGS16 inhibits signal transduction by increasing the GTPase activity of G protein alpha subunits thereby driving them into their inactive GDP-bound form. RGS16 Binds to G(i)-alpha and G(o)-alpha, but not to G(s)-alpha. RGS16 regulates the kinetics of signaling in the phototransduction cascade.

Chondrolectin (CHODL) is a type I membrane protein with a carbohydrate recognition domain characteristic of C-type lectins in its extracellular portion. In other proteins, this domain is involved in endocytosis of glycoproteins and exogenous sugar-bearing pathogens. The CHODL protein localizes mainly to the perinuclear region.

Dendritic cell and monocyte chemokinelike protein (DMC/CXCL17/VEGF-correlated chemokine 1/VCC1), is a secreted molecule with a size and predicted 3-dimensional folding pattern similar to that of chemokines CXCL8/IL8 and CXCL14/BRAK. CXCL17 is constitutively generated by airway and intestinal epithelium. CXCL17 induces the chemotaxis of quiescent, but not LPS-activated peripheral blood monocytes and dendritic cells, and it also binds these cells specifically. The expression of CXCL17 is increased in endothelial cells when they are induced to form tubes in vitro. CXCL17, CXCL1/GRO and CXCL8/IL8 which have roles in angiogenesis, show significantly correlated expression with that of VEGF in primary lung, breast and esophageal tumors. Therefore, CXCL17 is suggested to have a role in tumor angiogenesis. The mature Rat CXCL17 shares 82%, 71% amino acid sequence identity with mouse, human CXCL17, respectively.

Ubiquitin D (UBD) is an ubiquitin-like modifier (UBL) of the ubiquitin protein family. UBD is an ubiquitin-like protein which can form covalent conjugates, thus targeting proteins for degradation by the 26S proteasome. It is assumed that, UBD has roles in regulation of cell cycle, innate immunity, and apoptosis. UBD is a TNF-a inducible ubiquitin-like protein with a presumed role in the immune response.

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.

Receptor-associated Protein (aka RAP) averts the GCM-mediated enhancement of axon growth- ApoE-containing lipoproteins which are known to bind to receptors of the LDLr superfamily. In the presence of RAP, GCM doesn’t increase the axon extension rate in relation to base medium. Furthermore, the addition of RAP to the base medium doesn’t change the rate of axon extension. This implies that the growth stimulatory effect of apoE-containing lipoproteins secreted by glial cells is mediated by the LDLr family receptors. RAP annuls the growth stimulatory effect of GCM.

The protein kinase A holoenzyme is a heterotetramer composed of two types of subunits: Catalytic and Regulatory. The Catalyticsubunit contains the enzyme's active site. It also contains a domain that binds ATP and a domain that binds the regulatory subunit. The Regulatory subunit consists oftwo molecules which bind one another in an anti-parallel orientation to form a homodimer; for type I subunits- this binding is covalent via disulfide bonds. This subunit also has has two domains that bind cyclic AMP, a domain that interacts with a catalytic subunit, and an "auto-inhibitory" domain that serves as a substrate or pseudosubstrate for the catalytic subunit. Regulatory subunits may also have biologic activity distinct from their role in modulating catalytic subunit activity. Regulatory subunits exist in two major forms, RI and RII, with each form having two subtypes designated alpha and beta. Each of the four isotypes of the regulatory subunit is encoded by a different gene. In addition, three isotypes of the catalytic subunit have been identified (alpha, beta and gamma). The different isotypes tend to have different distributions within cells and among tissues. Type I enzymes inhabit cytoplasmic, soluble fractions of the cell, whereas type II enzymes tend to associate with cellular membranes.

Ribosomes, the organelles which catalyze protein synthesis, contain a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and nearly 80 structurally different proteins. RPL34 is a member of the L34E family of ribosomal proteins and it encodes a ribosomal protein which is a component of the 60S subunit. RPL34 is found in the cytoplasm and has been mapped to 4q though it was initially believed it is located at 17q21. Transcript variants which are a result of alternative splicing, alternative transcription initiation sites, and/or alternative polyadenylation exist; all encode the same protein. As is typical for genes encoding ribosomal proteins, there are several processed pseudogenes of this gene spread all over the genome.

AKAP7 is a member of the A-kinase anchoring protein (AKAP) family, a group of functionally related proteins which bind to a regulatory subunit (RII) of cAMP-dependent protein kinase A (PKA) and target the enzyme to specific subcellular sections. AKAP7 is expressed in heart, brain, pancreas, lung and skeletal muscle. AKAP7 binds PKA to the plasma membrane, and allows efficient coupling to the L-type calcium channel.

Integrin Beta 3 Binding Protein (ITGB3BP1) is a broadly expressed protein which contains a DD1 or RepD1 domain and an LXXLL motif. ITGB3BP1 functions as a nuclear receptor coactivator while induced by estrogen. ITGB3BP1 is also relates with the CENP-A-CAD complex that is engaged in mitotic progression, the assembly of kinetochore proteins and chromosome segregation. ITGB3BP1 behave s as a transcriptional corepressor via its interaction with the NFKB1 NF-kappa-B subunit by interfering with the transactivation domain of NFKB1.

SecB, a significant chaperone that takes part in protein export, binds various ligands rapidly with high affinity and low specificity. SecB plays an important role during protein export through the general secretory pathway by modulating the partitioning of precursors between folding or aggregation and delivery to the membrane-bound translocation apparatus. SecB has the potential to take part in functions outside of export acting as a universal nonspecific chaperone to provide buffering capacity of the nonnative state of proteins in the cytosolic pool.

RGS10 is a member of the RGS family that regulate molecules which perform as GTPase activating proteins (GAPs) for G alpha subunits of heterotrimeric G proteins. RGS proteins can disengage G protein subunits of the Gi alpha, Go alpha and Gq alpha subtypes. They drive G proteins into their inactive GDP-bound forms. All RGS proteins share a conserved 120-amino acid sequence termed the RGS domain. The nucleus localized RGS10 is associates specifically with the activated forms of the two related G-protein subunits, G-alphai3 and G-alphaz but is unable to cooperate with the structurally and functionally distinct G-alpha subunits.

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.

PTP4A2 is part of a small class of the protein tyrosine phosphatase (PTP) family. PTP4A2 is localized to the early endosome that take part in a variety of cellular activities. PTP4A2 protein interacts with the beta-subunit of Rab geranylgeranyltransferase II (beta GGT II), therefore has a role as a regulator of GGT II activity. Overexpression of PTP4A2 in mammalian cells conferred a transformed phenotype, which suggested its role in tumorigenesis.