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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.

CMV belongs to the Betaherpesvirinae subfamily of Herpesviridae which includes herpes simplex virustypes 1 and 2, varicella-zoster virus, and Epstein-Barrvirus. The herpesviruses share a characteristic ability to remain latentover long periods. CMV is a double-stranded linear DNA virus with 162 hexagonal protein capsomeres surrounded by a lipid membrane. CMV has the largest genome of the herpes viruses, ranging from 230-240 kilobase pairs. Human CMV is composed of unique and inverted repeats that include the existence of 4 genome isomers caused by inversion of L-S genome components (class E). Replication may be divided into immediate early, delayed early, and late gene expression based on time of synthesis after infection. The DNA is replicated by rolling circles. In vitro, CMV replicates in human fibroblasts.

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.

Decorin (DCN) is a small cellular or pericellular matrix proteoglycan which is closely related in structure to biglycan protein. Decorin is a secreted protein which binds to collagen and fibronectin in extracellular matrix. Decorin appears in different glycoforms, substituted with chondroitin sulfate or dermatan sulfate consistent with the original tissue. DCN contains one attached glycosaminoglycan chain. Decorin influences the rate of fibril formation. Decorin is capable of suppressing the growth of various tumor cell lines. DCN gene defects cause corneal dystrophy. The DCN gene is a candidate gene for Marfan syndrome.

Follistatin is a single-chain gonadal protein that specifically inhibits follicle-stimulating hormone release. The single FST gene encodes two isoforms, FST317 and FST344 containing 317 and 344 amino acids respectively, resulting from alternative splicing of the precursor mRNA. In a study in which 37 candidate genes were tested for linkage and association with polycystic ovary syndrome (PCOS) or hyperandrogenemia in 150 families, evidence was found for linkage between PCOS and follistatin. Follistatin binds directly to activin and functions as an activin antagonist. specific inhibitor of the biosynthesis and secretion of pituitary follicle stimulating hormone (fsh).

T-cell surface glycoprotein CD3 zeta chain (CD247) is a member of the CD3Z/FCER1G family. CD247 is T-cell receptor zeta, which along with T-cell receptor alpha/beta and gamma/delta heterodimers, and also with CD3-gamma, -delta and -epsilon, creates the T-cell receptor-CD3 complex. The zeta chain has a central role in coupling antigen recognition to several intracellular signal-transduction pathways. Low expression of the CD247 antigen causes impaired immune response.

Chromogranin A is a 439 amino acid protein which is encoded on chromosome 14 and is present in neuroendocrine cells throughout the body, including the neuroendocrine cells of the large and small intestine, adrenal medulla and pancreatic islets. It is an excellent marker for carcinoid tumors, phenochromocytomas, paragangliomas, and other neuroendocrine tumors.
Coexpression of chromogranin A and neuron specific enolase (NSE) is common in neuroendocrine neoplasms.

Clusterin also named Apolipoprotein J (APO-J) is a 75-80 kD disulfide-linked heterodimeric protein containing about 30% of N-linked carbohydrate rich in sialic acid but truncated forms targeted to the nucleus have also been identified.
The precursor polypeptide chain is cleaved proteolytically to remove the 22-mer secretory signal peptide and subsequently between residues 227/228 to generate the a and b chains. These are assembled in anti-parallel to give a heterodimeric molecule in which the cysteine-rich centers are linked by five disulfide bridges and are flanked by two predicted coiled-coil a-helices and three predicted amphipathic a-helices.
Across a broad range of species clusterin shows a high degree of sequence homology ranging from 70% to 80%. It is nearly ubiquitously expressed in most mammalian tissues and can be found in plasma, milk, urine, cerebrospinal fluid and semen.
It is able to bind and form complexes with numerous partners such as immunoglobulins, lipids, heparin, bacteria, complement components, paraoxonase, beta amyloid, leptin and others. Clusterin has been ascribed a plethora of functions such as phagocyte recruitment, aggregation induction, complement attack prevention, apoptosis inhibition, membrane remodeling, lipid transport, hormone transport and/or scavenging, matrix metalloproteinase inhibition.
A genuine function of clusterin has not been defined. One tempting hypothesis says that clusterin is an extracellular chaperone protecting cells from stress induced insults caused by degraded and misfolded protein precipitates.
Clusterin is up- or down regulated on the mRNA or protein level in many pathological and clinically relevant situations including cancer, organ regeneration, infection, Alzheimer disease, retinitis pigmentosa, myocardial infarction, renal tubular damage, autoimmunity and others.

MAGE belongs to the MAGE gene family, that comprises 12 known genes, of which 6 are expressed in tumors. The Melanoma-associated antigen 3 genes were originally isolated from different kinds of tumors, and based on their virtually limited tumor-specific expression in adult tissues, they were used as targets for cancer immunotherapy. MAGEA3 is a tumor-specific antigen extensively expressed in solid and hematologic malignancies, but not in normal tissues, with the exclusion of testis and placenta. Consequently, MAGEA3 is an outstanding candidate tumor antigen.

PDCD12 (AVEN) represents a new class of cell death regulator. PDCD12 is a conserved intracellular membrane protein which blocks apoptosis impeded by Apaf-1 mediated caspase activation. BAD and Bcl-2 also interact with PDCD12 to prevent apoptosis. PDCD12 is expressed in a wide variety of normal tissues including the heart, skeletal muscle, kidney, liver, testis, and also in diseases such as cancer.

Chemokine (C-X-C motif) ligand (CXCL7) is a small cytokine belonging to the CXC chemokine family. It is a protein that is released in large amounts from platelets following their activation. It stimulates various processes including mitogenesis, synthesis of extracellular matrix, glucose metabolism and synthesis of plasminogen activator.

Casein kinase I gene family members take part in the control of cytoplasmic and nuclear processes, including DNA replication and repair. Casein Kinase 1 Delta (CSNK1D) is a member of the casein kinase I (CKI) gene family. CSNK1D is a vital serine/threonine-protein kinase which regulates diverse cellular growth and survival processes including Wnt signaling and circadian rhythms. CSNK1D phosphorylates a great amount of proteins.

Mouse CXCL16 is a nonELR motif including CXC chemokine with a transmembrane domain. Mouse CXCL16 cDNA encodes a 246 a.a. precursor protein with a putative 26 a.a. residue signal peptide, an 88 a.a. residue chemokine domain, an 87 a.a. residue mucinlike spacer region, a 22 a.a. residue transmembrane domain, and a 23 a.a. residue cytoplasmic tail.
CXCL16 induces a strong chemotactic response and calcium mobilization. Furthermore, CXCL16 acts as a scavenger receptor on macrophages, which specifically binds to OxLDL (oxidized low density lipoprotein), suggesting that it may be involved in pathophysiology such as atherogenesis.
Mouse CXCL16 is generated by dendritic cells in lymphoid organ T cell zones as well as by cells in the splenic red pulp both as membranebound and soluble forms. CXCR6/Bonzo (STRL33 and TYMSTR) is the receptor for CXCL16. CXCL16 is expressed in the spleen, lymph nodes, and Peyer patches. It is also expressed in non-lymphoid tissues such as lung, kidney, small intestine, and thymus, with weak expression in heart and liver and no expression in brain and purified B- and T-cells.
CXCL16 deficiency is linked to breast cancer progression. In addition, CXCL16 is involved in immunological liver injury by regulating T lymphocyte infiltration in liver tissue. Furtheremore, CXCL16 has a distinctive role in the maintenance of cardiac allograft tolerance mediated by natural killer T cells. Moreover, CXCL16 has a significant role in not only the production of IFN-gamma by NKT cells, but also promotion of Th1-inclined immune responses mediated by NKT cells.

Chemokine (C-C motif) ligand 11 (CCL11) is a small cytokine belonging to the CC chemokine family that is also known as eotaxin. CCL11 selectively recruits eosinophils by inducing their chemotaxis, and therefore, is implicated in allergic responses. The effects of CCL11 are mediated by its binding to a G-protein-linked receptor known as a chemokine receptor. Chemokine receptors for which CCL11 is a ligand include CCR2, CCR3 and CCR5. The gene for human CCL11 (scya11) is encoded on three exons and is located on chromosome 17.

Syntaxin is membrane integrated Q-SNARE protein participating in exocytosis. Syntaxin is composed of an N-terminal regulatory domain (Habc), a SNARE domain (known as H3), and a single C-terminal transmembrane domain. The SNARE (H3) domain binds to both synaptobrevin and SNAP-25 forming the core SNARE complex. Synaptic vesicles store neurotransmitters that are released during calcium-regulated exocytosis. The specificity of neurotransmitter release requires the localization of both synaptic vesicles and calcium channels to the presynaptic active zone. Syntaxins function in this vesicle fusion process. Syntaxins also serve as a substrate for botulinum neurotoxin type C, a metalloprotease that blocks exocytosis and has high affinity for a molecular complex that includes the alpha-latrotoxin receptor which produces exocytosis.

Synaptojanin 2 Binding Protein (SYNJ2BP) contains 1 PDZ (DHR) domain which binds to isoform 2A of SYNJ2 (through the unique motif in the C-terminus) and interacts with MAPK12.

SYT13 belongs to the great synaptotagmin protein family which contain 2 domains: cytoplasmic C terminus with two tandem C2 domains (C2A and C2B) and extracellular N-terminal transmembrane domain. Synaptotogmin family members have dissimilar biochemical properties and developmental profiles, and patterns of tissue distribution. Additionally, Synaptotogmins formulate homo- and heteromeric complexes with each other. Synaptotagmins operate as membrane traffickers in multicellular organisms.

CCDC104 also known as coiled-coil domain-containing protein 104 is a 342 amino acid protein that exists as two alternatively spliced isoforms. CCDC104 undergoes post-translational phosphorylation following DNA damage, most likely by either ATR or ATM. Among the diseases associated with CCDC104 are pancreatic cancer, and pancreatitis.

Fractalkine soluble form is chemotactic for t-cells and monocytes, but not for neutrophils. Fractalkine membrane-bound form promotes adhesion of those leukocytes to endothelial cells. Fractalkine regulates leukocyte adhesion and migration processes at the endothelium and binds to CX3CR1. Natural Human Fractalkine is produced as a long protein (373-amino acid) with an extended mucin-like stalk and a chemokine domain on top. The mucin-like stalk permits it to bind to the cell surface. Fractalkine gene is located on human chromosome 16 along with some CC chemokines known as CCL17 and CCL22.

Lipocalin-1 (LCN1) belongs to the lipocalin family of small secretory proteins. Lipocalins are extracellular transport proteins, which bind to various hydrophobic ligands. LCN1 protein is the principal lipid binding protein in tears and is overproduced in response to numerous stimuli including infection and stress. LCN1 is a marker for chromosome aneuploidy as well as an autoantigen in Sjogren's syndrome.

Chemokine (C-X-C motif) ligand 1 (CXCL1) is a small cytokine belonging to the CXC chemokine family that was previously called GRO1 oncogene, Neutrophil-activating protein 3 (NAP-3) and melanoma growth stimulating activity, alpha (MSGA-a). It is secreted by human melanoma cells, has mitogenic properties and is implicated in melanoma pathogenesis. CXCL1 is expressed by macrophages, neutrophilsand epithelial cells, and has neutrophil chemoattractant activity. CXCL1 plays a role in spinal cord development by inhibiting the migration of oligodendrocyte precursors and is involved in the processes of angiogenesis, inflammation, wound healing, and tumorigenesis. This chemokine elicits its effects by signaling through the chemokine receptor CXCR2. The gene for CXCL1 is located on human chromosome 4 amongst genes for other CXC chemokines.

RCAN2 is a member of the RCAN (Regulator of calcineurin) family that controls the activity of Calcineurin using a valine-rich region placed in their carboxyl tail. RCANs race against NFAT (nuclear factor of activated T-cells) to bind to the same docking site in calcineurin, and consequently inhibits or activates calcineurin activity. RCAN2 is a Ca(2+) dependent protein phosphatase which takes part in numerous neuornal functions.

DNAJC15 which is expressed ubiquitously and located on the membrane contains 1 J domain. In many advanced cases of ovarian adenocarcinoma DNAJC15 is absent or down-regulated, due to hypermethylation and allelic loss. Loss of expression correlates with increased resistance to antineoplastic drugs, such as cisplatin. DNAJC15is a crucial component of the TIM23 translocase complex and stimulates the ATPase activity of HSPA9.

KLRB1 has an inhibitory role on natural killer (NK) cells cytotoxicity which are lymphocytes who facilitate cytotoxicity and secrete cytokines subsequent to immune stimulation. Some genes of the C-type lectin superfamily, like the rodent NKRP1 family of glycoproteins, are expressed by NK cells and take part in NK cell function regulation. KLRB1 holds an extracellular domain with a few characteristic motifs of C-type lectins, a transmembrane domain, and a cytoplasmic domain. Due to its external C terminus KLRB1 is considered to be a type II membrane protein.