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Complement Factor B, also known as CFB, encodes complement factor B which is a component of the alternative pathway of complement activation. Factor B circulates in the blood as a single chain polypeptide. Once the alternative pathway is activated it is cleaved by complement factor D yielding the noncatalytic chain Ba and the catalytic subunit Bb. The active subunit Bb is a serine protease which connects with C3b to form the alternative pathway C3 convertase. Also, Bb is involved in the proliferation of preactivated B lymphocytes, while Ba inhibits their proliferation.

PHD finger protein 11 (PHF11) is a regulator of TH1-type cytokine gene expression. The decline in PHF11 expression observed with an AD-associated genotype may promote the intense TH2 reactions which characterize numerous allergic individuals. PHF11 is linked with raised total serum IgE levels, asthma and acute atopic dermatitis (AD) in children. Even though PHF11 includes a plant homeodomain, a motif frequently found in transcriptional regulators, PHF11 function of has yet been examined.

Secreted Frizzled-Related Protein 5, also known as SFRP5, belongs to the SFRP family which includes a cysteine-rich domain homologous to the putative Wnt-binding site of Frizzled proteins. SFRPs perform like soluble modulators of Wnt signaling. SFRP5 & SFRP1 are implicated in determining the polarity of photoreceptor cells in the retina. SFRP5 is highly expressed in the retinal pigment epithelium, as well as moderately expressed in the pancreas.

Caspase Recruitment Domain Family, Member 17 (CARD17) is a regulator of procaspase-1/CASP1 activation involved in the regulation of the proteolytic maturation of pro-IL-1beta/IL1B and its release throughout inflammation. CARD17 inhibits the release of IL1B in reaction to LPS in monocytes. Though, unlike CASP1, CARD17 do not induce NF-kappa-B activation.

Replication Protein A2 (RPA2) is a single stranded DNA binding protein. Human RPA2 is a heterotrimeric protein containing subunits of 14, 32 and 70kDa. The RPA2 protein complex is highly conserved in eukaryotes and is crucial in DNA replication, homologous recombination and nucleotide excision repair. RPA2 C-terminus specifically interacts with the DNA repair enzyme UNG2 and repair factors XPA and Rad52, each of which functions in a different repair pathway. Additionally, RPA2 binds specifically to the SH2 domain of Stat3 in vivo, and overexpression of RPA2 corresponds to the augmented growth factor-stimulated tyrosine phosphorylation and transcription activities of Stat3.

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.

ARL4A is related Specifically to ARL6 and ARL7 and belongs to the ARF-like protein (ARL) subfamily of small GTPases. However, unlike ARFs, ARL4 does not activate the cholera toxin ADP-ribosyltranferase. ARL4A takes part in neurogenesis during embryonic development and somitogenesis in the early stages of adult spermatogenesis.

Killer cell immunoglobulin-like receptor 2DL4, also known as KIR2DL4 is part of the killer cell Ig-like receptor (KIR) family. KIR proteins with the long cytoplasmic domain transduce inhibitory signals through an immune tyrosine-based inhibitory motif (ITIM), whereas KIR proteins which contain the short cytoplasmic domain, lack the ITIM motif and as a substitute associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals. KIR2DL4 stimulates NK cells to produce IFN-gamma and stimulation with IL-2 upregulates cell surface expression on CD56dimcells and leads to the inhibition of the cytolytic NK cell function.

Complement Factor D (Adipsin), which belongs to the trypsin family of peptidases, is involved in the alternative complement pathway of the complement system where it cleaves factor B. In the alternative complement pathway, Adipsin is best known for its role in humoral suppression of infectious agents. In addition, Adipsin is a serine protease which is secreted by adipocytes into the bloodstream. Ultimately, Adipsin has a high level of expression in fat, proposing a role for adipose tissue in immune system biology.

Glycophorins A & B (GYPA &GYPB) are the main sialoglycoproteins of the human erythrocyte membrane which carry the antigenic determinants for the MN and Ss blood groups. Along with the M or N and S or s antigens which normally occur in all populations, approximately 40 related variant phenotypes were identified. These variants comprise all the variants of the Miltenberger complex and some isoforms of Sta, as well as Dantu, Sat, He, Mg, and deletion variants Ena, S-s-U- and Mk. GYPA is significant for the function of SLC4A1 and is necessary for high activity of SLC4A1. GYPA is involved in translocation of SLC4A1 to the plasma membrane. GYPA is also a receptor for: the influenza virus, Plasmodium falciparum erythrocyte-binding antigen 175 (EBA-175); binding of EBA-175 is dependent on sialic acid residues of the O-linked glycans and is also a receptor for Hepatitis A virus (HAV).

BMP5 belongs to the bone morphogenetic protein family which is part of the transforming growth factor-beta superfamily. This superfamily is comprised of large families of growth and differentiation factors. Bone morphogenetic proteins were initially identified by their ability of demineralizing bone extract to induce endochondral osteogenesis in vivo in an extraskeletal site.
BMP5 is an essential signaling molecule within the trabecular meshwork and optic nerve head, and may play a potential role in glaucoma pathogenesis. It was shown that BMP-5 increases the levels of osteopontin, BMP-2, alkaline phosphatase and core binding factor alpha 1 mRNAs in human periodontal (HPL) ligament cells. The BMP5 protein is expressed in normal synovial tissue and reduced in osteoarthritis and rheumatoid arthritis. BMP5 may have a role in certain cancers given that it is differentially regulated during the formation of different tumors.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets and binds with high affinity to heparin. Its major physiologic role appears to be neutralization of heparin-like molecules on the endothelial surface of blood vessels, thereby inhibiting local antithrombin III activity and promoting coagulation. As a strong chemoattractant for neutrophils and fibroblasts, PF4 probably has a role in inflammation and wound repair. Oncostatin-A is a member of the CXC chemokine family. Human PF4 is used for the proof of heparin-induced thrombocytopenia. Furthermore it is used as an inhibitor in the angiogenesis during tumor therapy.

Epiregulin is part of the EGF family. Epiregulin functions as a ligand of EGFR, as well as a ligand of most members of the ERBB (v-erb-b2 oncogene homolog) family of tyrosine-kinase receptors.Epiregulin is expressed mostly in the placenta and peripheral blood leukocytes and in specific carcinomas of the bladder, lung, kidney and colon. Epiregulin stimulates the proliferation of keratinocytes, hepatocytes, fibroblasts and vascular smooth muscle cells. Epiregulin inhibits the growth of several tumor-derived epithelial cell lines. Human Epiregulin is initially synthesized as a glycosylated 19.0 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a 6.0 kDa mature secreted sequence.

Ubiquitin thioesterase OTUB2 (OTUB2) is a member of the peptidase C65 family. OTUB2 functions as a hydrolase which can remove conjugated ubiquitin from proteins in vitro and may thus play a key regulatory role at the level of protein turnover by preventing degradation.

GNLY is part of the SAPLIP family and is located in the cytotoxic granules of T cells, which are discharged upon antigen stimulation. GNLY is localized in cytotoxic granules of cytotoxic T lymphocytes and natural killer cells, and it has antimicrobial activity against M. tuberculosis and other organisms. GNLY is an antimicrobial protein that kills intracellular pathogens. GNLY is active against a wide range of microbes, including Gram-positive and Gram-negative bacteria, fungi, and parasites. Kills Mycobacterium tuberculosis.

Pirin (PIR) which belongs to the cupin superfamily, is an Fe(II)-containing nuclear protein expressed in all tissues of the body and concentrated within dot-like subnuclear structures. Pirin may function as a transcriptional cofactor and is involved in the regulation of DNA transcription and replication, as a result of interactions with nuclear factor I/CCAAT box transcription factor as well as B cell lymphoma 3-encoded oncoprotein.

The bone morphogenetic protein (BMP) receptors are a family of transmembrane serine/threonine kinases that include the type I receptors BMPR1A and BMPR1B and the type II receptor BMPR2. These receptors are also closely related to the receptors, ACVR1 and ACVR2. The ligands of these receptors are members of the TGF-beta superfamily. TGF-betas transduce their signals through the formation of heteromeric complexes with 2 different types of serine (threonine) kinase receptors: type I receptors of about 50-55 kD and type II receptors of about 70-80 kD. Type II receptors bind ligands in the absence of type I receptors, but they require their respective type I receptors for signaling, whereas type I receptors require their respective type II receptors for ligand binding.

INHBC, the beta C chain of inhibin, belongs to the TGF-beta superfamily. INHBC formulates heterodimers with beta A and beta B subunits. Other members of the TGF-beta superfamily are Actv's and Inhibins, hormones with contradictory roles which take part in pituitary, hypothalamic, and gonadal hormone secretion, as well as differentiation and growth of numerous cell types.

Smac/Diablo is a proapoptotic protein that increases caspase activation in the cytochrome c/Apaf-1/caspase-9 pathway by its binding to the inhibitor of apoptosis proteins (IAPs) and removing their inhibitory activity. Smac/Diablo is a mitochondrial protein which enters the cytosol when cells go through apoptosis, and it moderates the caspase inhibition of IAPs.
Smac/DIABLO expression is associated with the result of renal cell carcinoma.
Dimeric form of Smac/DIABLO implies that once expressed in the cell the protein has a little probability of dissociation and, thus, loss of function.
Survivin, Smac/DIABLO, & PKC-? play an important part in the inhibition of apoptosis by FGF-2 in human small cell lung cancer cells. Mitochondrial survivin associates with Smac/DIABLO, delaying its release. Decreased expression of Smac protein takes part in ovarian carcinogenesis and chemotherapeutic resistance. Smac/DIABLO plays a role in tumor cells during the pathway of apoptosis induction. SMAC protein is regulated by XIAP and degraded by proteasome. SMAC protein takes part inleukemic cell apoptosis.
Smac is released during stress-induced apoptosis in multiple myeloma cells.

TCEB1 (elongin C) is a subunit of elongin, which is a common transcription elongation factor that increases the RNA polymerase II transcription elongation past template encoded arresting sites. The SIII complex is comprised of elongins A/A2, B and C. The SIII complex activates elongation by RNA polymerase II by curbing transient pausing of the polymerase at numerous sites within transcription units. Elongin A acts as the transcriptionally active component of the SIII complex, while elongins B and C are regulatory subunits. Elongin A2 is specifically expressed in the testis, and able to forming a stable complex with elongins B and C. The VHL (von Hippel-Lindau) tumor suppressor protein binds to elongins B and C, and thus inhibits transcription elongation.

Crystallin Zeta, also known as CRYZ, Binds NADP and participates in a one-electron transfer process. CRYZ takes part in the detoxification of xenobiotics and Interacts with (AU)-rich elements (ARE) in the 3'-UTR of target mRNA species. CRYZ improves the mRNA coding for BCL2.

REG protein was shown to be stimulated during the regeneration of pancreatic islets. Since then, many Reg-related proteins have been identified in humans and other animals. In human, the four REG family genes, i.e., REG 1 alpha, REG 1 beta, REG-related sequence (RS) and HIP/PAP, have so far been isolated. These Reg-related proteins are classified into four subfamilies according to their amino-acid sequences, but they share a similar structure and physiological function. Reg protein is a growth factor for pancreatic beta cells and also suggests that the administration of Reg protein could be used as another therapeutic approach for diabetes mellitus. Human REG cDNA which encodes a 166-amino acid protein with a 22-amino acid signal peptide. The amino acid sequence of human REG protein has 68% homology to that of rat Reg protein.
Reg I was found to be expressed mainly in pancreatic beta and acinoductular cells as well as gastric fundic enterochromaffin-like (ECL) cells. Reg I production in ECL cells is stimulated by gastrin, as well as by the proinflammatory cytokine, cytokine-induced neutrophil chemoattractant (CINC)-2Beta. In patients with chronic hypergastrinemia, Reg production is stimulated, with the increased proliferation of gastric mucosal cells. Patients with Helicobacter pylori infection also showed increased Reg production in the gastric mucosa, partly via increased plasma gastrin concentration and partly via increased proinflammatory cytokine production. The serum concentration of the reg-protein was significantly higher in patients with various pancreatic diseases than in normal controls, and was also significantly higher in patients with acute pancreatitis or chronic relapsing pancreatitis than in patients with chronic pancreatitis. Furthermore, the serum PSP/reg-protein concentration was also significantly increased in liver cirrhosis, choledocholithiasis, and various cancers of the digestive system.