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Listeriolysin O (aka LLO) is a hemolysin produced by Listeria monocytogenes bacteria, the pathogen responsible for causing listeriosis. The toxin may be regarded as a virulence factor, since it is crucial for the virulence of L. monocytogenes. LLO is a single polypeptide protein encoded by the hlyA gene and composed of 529 residues. LLO is a thiol-activated cholesterol-dependent pore forming toxin protein; therefore, it is activated by reducing agents and inhibited by oxidizing agents. Still, LLO differs from other thiol-activated toxins, as its cytolytic activity is maximized at a pH of 5.5. Inside the acidic phagosomes (average pH ~ 5.9) of cells that have phagocytosed L. monocytogenes, LLO is selectively activated by maximizing activity at a pH of 5.5. Following the phagosome lysis by LLO, the bacterium breaks out into the cytosol, where it is able to grow intracellularly, and the toxin has reduced activity in the more basic cytosol. Thus, LLO permits L. monocytogenes to break out from the phagosomes into the cytosol without harming the plasma membrane of the infected cell, which allows the bacteria to live intracellularly, where they are sheltered from extracellular immune system factors such as the complement system and antibodies. LLO also brings about dephosphorylation of histone H3 and deacetylation of histone H4 in the early phases of infection, before entry of L. monocytogenes into the host cell. The pore-forming activity is not implicated in causing the histone modifications. The modifications of the histones affect the down regulation of genes encoding proteins involved in the inflammatory response. Therefore, LLO may be significant in subverting the host immune response to L. monocytogenes. At its NH2-terminus it possesses a 25 residues long typical signal sequence excited during the secretion process. Moreover, in its NH2-terminus there is also a 19 amino acids PEST- like sequence that may target this toxin for degradation. The PEST-like sequence found in LLO and is considered crucial for virulence, given that mutants lacking the sequence lysed the host cell. Nevertheless, contrary to PEST's supposed role in protein degradation, evidence implies that the PEST-like sequence may control LLO production in the cytosol rather than increase degradation of LLO.

SAA1 protein is an acute phase apolipoprotein reactant which is produced mostly by hepatocytes and under regulation of inflammatory cytokines. SAA1 (Serum amyloid A1) protein is produced mainly in the liver and circulates in low levels in the blood. The SAA1 seems to have a role in the immune system. SAA1 protein levels increase in the blood and other tissues under conditions of inflammation. SAA1 may facilitate the repair of injured tissues; it also acts as an antibacterial agent, and signals the migration of germ-fighting cells to sites of infection. SAA1 also functions as an apolipoprotein of the HDL complex.
Elevated levels of SAA1 ultimately affect secondary amyloidosis, extracellular amassing of amyloid fibrils, resulting from a circulating precursor, in a variety of tissues and organs. The most widespread type of amyloidosis appears secondary to chronic inflammatory disease, mainly rheumatoid arthritis. The SAA1 cleavage product a designated amyloid protein A is deposited systemically as amyloid in vital organs such as the liver, spleen, and kidneys in chronic inflammatory diseases patients. These deposits are extremely insoluble and resistant to proteolysis; they disrupt tissue structure and compromise performance.

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.

Elongin B (Elob) is a subunit of the transcription factor B (SIII) complex. SIII complex is a general transcription elongation factor that increases the RNA polymerase II transcription elongation past template-encoded arresting sites. The SIII complex comprised of a transcriptionally active subunit (A) and 2 regulatory subunits (B and C). Subunit A is transcriptionally active and its transcription activity is enhanced by binding to the dimeric complex of the SIII regulatory subunits B and C. The von Hippel-Lindau tumor suppressor protein binds to elongin B and C and inhibits transcription elongation.

Osteoprotegerin acts as decoy receptor for rankl and thereby neutralizes its function in osteoclastogenesis. OPG inhibits the activation of osteoclasts and promotes osteoclast apoptosis in vitro. Bone homeostasis seems to depend on the local rankl/opg ratio. Osteoprotegerin may also play a role in preventing arterial calcification. May act as decoy receptor for trail and protect against apoptosis. Trail binding blocks the inhibition of osteoclastogenesis.

IL-1 alpha is produced by activated macrophages.IL-1 alpha stimulates thymocyte proliferation by inducing il-2 release, b-cell maturation and proliferation, and fibroblast growth factor activity. IL1A proteins take part in the inflammatory response, being identified as endogenous pyrogens, and stimulate the release of prostaglandin and collagenase from synovial cells.

XCL1 is a small cytokine belonging to the XC chemokine family that is also known as lymphotactin. It is located in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to another chemokine called XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

TNFSF12 is a cytokine that is part of the TNF ligand family. TNFSF12 is a ligand for the FN14/TWEAKR receptor. TNFSF12 has overlapping signaling functions with TNF, but displays a much wider tissue distribution. TNFSF12 induces apoptosis through multiple pathways of cell death in a cell type-specific manner. TNFSF12 promotes proliferation and migration of endothelial cells, and therefore acts as a regulator of angiogenesis. TNFSF12 is expressed in adult heart, pancreas, skeletal muscle, small intestine, spleen and peripheral blood lymphocytes. TWEAK h induces NFkB and chemokine secretion. TNFSF12 exerts an apoptotic activity in HT-29 human adenocarcinoma cells whilst cultured in the presence of IFN-?. TNFSF12 promotes proliferation and migration of endothelial cells.

TNF-related apoptosis-inducing ligand (TRAIL) is a ligand molecule which induces apoptosis. It is a type II transmembrane protein with homology to other members of the tumor necrosis factor family.
In humans, the gene that encodes for TRAIL is located at chromosome 3q26.
TRAIL binds to the death receptors, DR4 and DR5. The process of apoptosis is caspase-8-dependent. This protein preferentially induces apoptosis in transformed and tumor cells, but does not appear to kill normal cells although it is expressed at a significant level in most normal tissues.

TOLLIP is a ubiquitin-binding protein that interacts with several Toll-like receptor (TLR) signaling cascade components. TOLLIP regulates inflammatory signaling and is involved in interleukin-1 receptor trafficking and in the turnover of IL1R-associated kinase.

Glia Maturation Factor-Beta (GMF-Beta) is a 17 kDa protein nerve gorwth factor identified as a growth and differentiation factor in the vertebrate brain.

Glia Maturation Factor-Beta stimulates differentiation of normal neurons as well as glial cells. GMFB inhibits the proliferation of the N-18 neuroblastoma line and the C6 glioma line while promoting their phenotypic expression.
GMF-beta inhances the phenotypic expression of glia & neurons thus inhibits the proliferation of their respective tumors when added to cell culture. Although astrocytes produce GMF-b and stores it inside the cells, they don’t secrete the GMF-B into the cultured medium. Cell- surface GMFb acts on the target cells at close range when cells are in direct contact. GMF-Beta is produced by thymic epithelial cells and plays an important role in T cell development in favor of CD4+ T cells.
GMF-Beta is a brain-specific protein which belongs to the actin-binding proteins (ADF) family. GMF-beta appears to play a role in the differentiation, maintenance, and regeneration of the nervous system. It also supports the progression of certain auto-immune diseases, possibly through its ability to induce the production and secretion of various pro-inflammatory cytokines.

SCGN is a secreted calcium-binding protein which is found in the cytoplasm. It is related to calbindin D-28K and calretinin. Secretagogin is involved in KCL-stimulated calcium flux and cell proliferation.
Secretagogin plays a role in human non-functional pituitary adenomas.

DCTN2 is a 50kDa subunit of dynactin, which is a macromolecular complex consisting of 10-11 subunits ranging in size from 22 to 150 kDa. Dynactin binds to both microtubules and cytoplasmic dynein. Dynactin is involved in a various cellular functions, including ER-to-Golgi transport, the centripetal movement of lysosomes and endosomes, spindle formation, chromosome movement, nuclear positioning, and axonogenesis. The DCTN2 subunit is present in 4-5 copies per dynactin molecule. DCTN2 is comprised of 3 short alpha-helical coiled-coil domains which mediate association with self or other dynactin subunits. DCTN2 interacts directly with the largest subunit (p150) of dynactin and is able to affix p150 in place. DCTN2 modulates cytoplasmic dynein binding to an organelle, and plays a part in prometaphase chromosome alignment and spindle organization during mitosis. DCTN2 is involved in anchoring microtubules to centrosomes. DCTN2 has a role in synapse formation during brain development.

CD166 antigen isoform 2 (ALCAM) is a type 1 membrane glycoprotein and belongs to the immunoglobulin superfamily. ALCAM is expressed on thymic epithelium, microvascular endothelium, activated lymphocytes and monocytes, and monocyte-derived dendritic cells. CD166 and CD6 interaction plays a role in T cell development and T cell regulation, as well as in the binding of T cells and B cells to activated leukocytes.

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.

Sialic acid-binding Ig-like lectin 6 isoform 1 (SIGLEC6) is a member of immunoglobulin superfamily and SIGLEC (sialic acid binding Ig-like lectin) family. SIGLEC6 mediates sialic-acid dependent binding to cells and binds to alpha-2, 6-linked sialic acid. The SIGLEC6 protein localizes in numerous compartments such as membrane fraction, extracellular region and so on. The SIGLEC6 receptor binds sialyl-TN glycans and leptin. Placental expression SIGLEC6 is upregulated in preeclampsia.

EDA2R (ectodysplasin A2 receptor) mediates the activation of the NF-kappa-B and JNK pathways. Activation seems to be mediated through binding to TRAF3 and TRAF6. In addition, Mutations in EDA give rise to a clinical syndrome characterized by loss of hair, sweat glands, and teeth. EDA2R specifically binds to EDA-A2 isoform. This protein is a type III transmembrane protein of the TNFR (tumor necrosis factor receptor) superfamily, and contains 3 cysteine-rich repeats and a single transmembrane domain however it lacks an N-terminal signal peptide. Alternatively spliced transcript variants have been found for this gene. Among the diseases associated with EDA2R are ectodermal dysplasia 1, hypohidrotic, x-linked, and hypohidrotic ectodermal dysplasia.

NPM2 is a member of nucleoplasmin family. NPM2 is a core histones chaperone which takes part in chromatin reprogramming, particularly throughout fertilization and early embryonic development. NPM2 also takes part in sperm DNA decondensation during fertilization.

Oncostatin M is a member of a cytokine family that includes leukemia-inhibitory factor, granulocyte colony-stimulating factor, and interleukin 6. This gene encodes a growth regulator which inhibits the proliferation of a number of tumor cell lines. It regulates cytokine production, including IL-6, G-CSF and GM-CSF from endothelial cells.

FAM3B Protein induces apoptosis of alpha and beta cells in a quantity and time dependent way.

Transcription Factor 4 (TCF4) acts as a transcription factor and takes part in the initiation of neuronal differentiation. TCF4 recognizes an Ephrussi-box ('E-box') binding site ('CANNTG') - a motif primary identified in immunoglobulin enhancers. TCF4 is mainly expressed in pre-B-cells, even though it is present in other tissues as well.

Fibroblast Growth Factors (FGFs) comprise a family of at least eighteen structurally realted proteins that are involved in a multitude of physiological and pathological cellular processes, including cell growth, differentation, angiogenesis, wound healing and tumorgenesis. The biological activities of the FGFs are mediated by a family if type I transmembrane tyrosine kinases which undergo dimerization and autophosphorylation after ligand binding. Four distinct genes encoding closely related FGF receptors, FGFR-1to -4 are known. Multiple forms of FGFR-1 to -3 are generated by alternative splicing of the mRNAs. A frequent splicing event involving FGFR-1 and -2 results in receptors containing all three Ig domains, referred to as the alpha isoform, or only IgII and IgIII, referred to as the ? isoform. Only the alpha isoform has been identified for FGFR-3 and FGFR-4. Additional splicing events for FGFR-1 to -3, involving the C-terminal half of the IgIII domain encoded by two mutually exclusive alternative exons, generate FGF receptors with alternative IgIII domains (IIIb and IIIc). A IIIa isoform which is a secreted FGF binding protein containing only the N-terminal half of the IgIII domain plus some intron sequences has also been reported for FGFR-1. Mutations in FGFR-1 to -3 have been found in patients with birth defects involving craniosynostosis.