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Plasma protease C1 inhibitor (SERPING1) is a part of the serpin superfamily of serine protease inhibitors. SERPING1 plays an important role in regulating activation of both the complement and contact systems. SERPING1 is also activating C1 by coupling with the active catalytic site at the light chains of C1r and C1s. SERPING1 insufficiency results in hereditary angioedema, which is characterized by recurrent episodes of localized angioedema of the skin, gastrointestinal mucosa or upper respiratory mucosa.

The Argonaute protein is part of the RISC or RNA-induced silencing complex, as so, the protein has a key part in the slicing processes of RNA. The RNA interference (RNAi) is being held by RISC. Small non-coding RNA fragments bond to the Argonaute proteins, through base pairing, eventually leads to the cleavage of messenger RNA or translation suppression.

A fusion tag called FLAG consists of eight amino acids (AspTyrLysAspAspAspAspLys) including an enterokinase-cleavage site. FLAG is specifically designed for immunoaffinity chromatography. It allows elution under non-denaturing conditions. Several antibodies against this peptide have been developed. One antibody denoted as M1 binds the peptide in the presence of bivalent metal cations preferably Ca(+). Elution is effected by chelating agents. Another strategy is competitive elution with excess of free Flag Peptide. The FLAG peptide purifies and detects recombinant fusion proteins. FLAG peptide is useful in Western blotting, immunocytochemistry, immunoprecipitation, flow cytometry, protein purification, and in the study of protein-protein interactions, cell ultrastructure, and protein localization. Flag peptide is a hydrophilic tag which significantly improves the detection and purification of recombinant fusion proteins.

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.

Prohibitin (PHB) is an evolutionarily conserved gene that is ubiquitously expressed and which Mutations have been linked to sporadic breast cancer. PHB is thought to be a negative regulator of cell proliferation and may be a tumor suppressor. Prohibitin is expressed as two transcripts with changeable lengths of 3' untranslated region. The longer transcript is present at higher levels in proliferating tissues and cells, proposing that this longer 3' untranslated region functions as a trans-acting regulatory RNA.

Pleckstrin homology-like domain family A member 2 (PHLDA2) is a cytoplasmic protein, which is involved in fetal and placental growth. PHLDA2 is an apoptosis-related protein, which acts as a negative growth regulator and is expressed during normal human development. PHLDA2 is imprinted on placenta, liver and fetal tissues during embryogenesis and is removed once development is complete. The PHLDA2 gene is one of a number of genes in the imprinted gene domain of 11p15.5 which is considered to be an important tumor suppressor gene region. Changes in this region may be linked to the Beckwith-Wiedemann syndrome, Wilms tumor, rhabdomyosarcoma, adrenocortical carcinoma, and lung, ovarian, and breast cancer. PHLDA2 is expressed in placenta (present in all cells of the villous cytotrophoblast) and adult prostate gland. Furthermore, PHLDA2 is expressed in adult brain and neuroblastoma, medullablastoma and glioblastoma cell lines and at low levels in adult liver and lung, and fetal liver.

L-Selectin belongs to a family of divalent cation-dependent carbohydrate-binding glycoproteins or adhesion molecules. The L-Selectin molecule is composed of various domains: one homologous to lectins, one to epidermal growth factor, and two to the consensus repeat units found in C3/C4 binding proteins.
L-selectin is expressed constitutively on lymphocytes, monocytes and granulocytes and interacts specifically with carbohydrate groups on activated endothelial cells. L-Selectin may be shed by proteolytic cleavage and circulating levels in biological fluids may be used as an indicator of various pathological conditions. L-Selectin is cleaved by ADAM17.
L-selectin works as a "homing receptor" for leukocytes to enter secondary lymphoid tissues via the high endothelial venules. Ligands present on endothelial cells will attach to leukocytes expressing L-selectin, which causes the leukocytes to become localized at that juncture. The receptor is also located on the cell surfaces of "naive" T cells, which have not yet encountered their particular antigen. This surface expression is lost following the cells activation.

Procalcitonin is a peptide hormone mainly produced by the C cells of the thyroid and certain endocrine cells of the lung. Under normal expression conditions, procalcitonin is immediately cleaved into three specific fragments, an N terminal residue, calcitonin and katacalcin. Levels of unprocessed procalcitonin rise significantly after bacterial infection, trauma or shock.

Human thyrostimulin ranks among the glycoprotein hormone family. These hormones consist of two subunits, the common alpha- and specific beta-subunits, which associate noncovalently to form a heterodimer. The alpha-subunit combines with four distinct beta-subunits giving rise to four biologically active hormones in human: FSH, LH, TSH, and CG. FSH, LH, and TSH, mainly expressed in the anterior pituitary, are essential for coordinated endocrine regulation in the hypothalamus- pituitary axis and show to activate specific G protein–coupled receptors in the thyroid (TSH receptor) and gonads (LH and FSH receptors), respectively.
The heterodimeric glycoprotein hormones have only been identified in vertebrates and are highly conserved in organisms from primitive rayfin fish (Chondrostei) to human in both primary sequences and functional characteristics.
Corticotroph-derived glycoprotein hormone (CGH), also referred to as thyrostimulin, is a noncovalent heterodimer of glycoprotein hormone alpha 2 (GPHA2) and glycoprotein hormone beta 5 (GPHB5).
Recombinant A2/B5 heterodimeric glycoproteins activates human TSH receptors, but not LH and FSH receptors, and shows high affinity to TSH receptors in a radioligand receptor assay. The heterodimer also stimulates cAMP production and thymidine incorporation by cultured thyroid cells and increases serum thyroxine levels in TSH-suppressed rats in vivo. This new heterodimeric glycoprotein hormone was named as thyrostimulin based on its thyroid-stimulating activity. The expression of thyrostimulin in the anterior pituitary known to express TSH receptors suggested a paracrine mechanism.

PTX3 is part of the pentraxin family sharing the C-terminal domain with short pentraxins and containing a unique N-terminal domain. PTX3 is produced and released at inflammatory sites by various cell types including monocytes/macrophages, endothelial cells, vascular smooth muscle cells, fibroblasts, and adipocytes. PTX3 is involved in the regulation of innate resistance to pathogens, inflammatory reactions, possibly clearance of self-components and female fertility. PTX3 is used as a marker for disease activity of psoriasis. High serum PTX3 levels are associated with the disease severity of systemic sclerosis. Elevated serum PTX3 is associated with pulmonary fungal infections.

GH-releasing peptides (GHRPs) are synthetic peptides that like GHRH effect on pituitary somatotrophs to stimulate GH release. The GHRP5 is one of several synthetic met-enkephalin analogs that owns unnatural D-amino acids. They were developed for their growth hormone (GH) releasing activity and called GH secretatogues. They lack opioid activity but are potent stimulators of GH release. These secretatogues are distinct from the growth hormone releasing hormone (GHRH or GHRF) as they share no sequence relation and derive their function through action at a completely different receptor, the ghrelin receptor.

Alpha crystallins are composed of two gene products ; alpha-A and alpha-B, for acidic and basic, respectively. Alpha crystallins can be induced by heat shock and are members of the small heat shock protein (sHSP also known as the HSP20). They act as molecular chaperones and hold them in in large soluble aggregates. These heterogeneous aggregates consist of 30-40 subunits; the alpha-A and alpha-B subunits have a 3:1 ratio, respectively. Two additional function of a-crystallins are an autokinase activity and participation in the intracellular architecture. Alpha-B is expressed widely in many tissues and organs and occurs in many neurological diseases.

Cyclophilin-G is a member of the peptidyl-prolyl cis-trans isomerase (PPIase) family. PPIases catalyze the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and speeds up the protein folding. PPIG catalyzes the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and is involved in the folding, transport, and assembly of proteins. PPIG is localized to the nuclear speckles, a nuclear compartment rich in splicing factors, and cooperates with the splicing factors SC35 and pinin. Cyclophilin-G also takes part in the regulation of pre-mRNA splicing.

AGR2 (Anterior gradient 2 homolog) is the human orthologue of the secreted Xenopus laevis Anterior Gradient protein (XAG-2). This is a small, possibly secreted molecule of yet weakly defined functions that is widely expressed in human tissues. Expression of AGR2 shows a positive correlation with expression of estrogen receptor in breast carcinoma and a negative correlation with expression of EGF receptor.

Dysbindin domain-containing protein 1 (DBNDD1) is a member of the dysbindin family.

HMGB3 is a member of the high mobility group (HMG) protein superfamily. HMGB3 holds DNA-binding HMG box domains, as do HMG1 and HMG2, and like the rest of the HMG protein superfamily members has a vital part in DNA replication, transcription and nucleosome assembly.

ARF1 is a small guanine nucleotide-binding protein that increases the enzymatic activities of cholera toxin. ARF1 is necessary and ubiquitous in eukaryotes. ARF1 takes part in vesicular transport and functioning via phospholipase D activation. ARF1 is involved in membrane traffic and organelle integrity which are closely tied to their reversible association with membranes and distinct interactions with membrane phospholipids.

Interferon Alpha and Beta Receptor Subunit 2 or IFNAR2 is a protein, part of the class II cytokine receptor family. When different innate immune signaling transduction are activated, there is a rapid induction of type I IFNs because it has an intronless gene source. IFNAR2 is the main ligand and binds to the receptor. Once bind, stabilization occurs and a signaling compelx recptor is formed. IFNAR2 also takes part in the activation process of STAT proteins.

Survivin is part of the of the inhibitor of apoptosis (IAP) family, which encodes negative regulatory proteins that prevent apoptotic cell death. Members of the IAP family include multiple baculovirus IAP repeat (BIR) domains, but Survivin has only a single BIR domain.
Survivin is an inhibitor of caspase activation therefore leading to negative regulation of apoptosis. BIRC5 is expressed in Merkel cell carcinoma.
BIRC5 polymorphism causes survivin expression, thus contributing to the genetic susceptibility to lung cancer. BIRC5 expression in large cell lung cancer is substantially higher than in normal tissue cells. Survivin mRNA is up-regulated in tumors. Apoptotic response of infected intestinal epithelial cells is suppressed by C. parvum via upregulation of BIRC5, favoring parasite infection. Up-regulation of of Survivin is associated with breast carcinomas.
BIRC5 increases the activity of an oncolytic adenovirus in the presence of low-dose radiotherapy. ER- breast cancer cells become dependent on Notch-survivin signaling for their maintenance, in vivo. Survivin mRNA positive cases are related with bladder tumour recurrence elevated expression of survivin might play an important role of development in nasal polyps.

ETHE1 is a mitochondrial sulfur dioxygenase involved in catabolism of sulfide that accumulates to toxic levels in ethylmalonic encephalopathy. Mutations of ETHE1 were detected in all the typical ethylmalonic encephalopathy patients analysed, but no ETHE1 mutations were identified in patients presenting with early onset progressive encephalopathy with ethylmalonic aciduria.

PDGF-BB is a member of the platelet-derived growth factor family. The four members of this family are mitogenic factors for cells of mesenchymal origin and are characterized by a motif of eight cysteines. This gene product can exist either as a homodimer (PDGF-BB) or as a heterodimer with the platelet-derived growth factor alpha polypeptide (PDGF-AB), where the dimers are connected by disulfide bonds. Mutations in this gene are associated with meningioma. Reciprocal translocations between chromosomes 22 and 7, at sites where this gene and that for COL1A1 are located, are associated with a particular type of skin tumor called dermatofibrosarcoma protuberans resulting from unregulated expression of growth factor. Two splice variants have been identified for this gene.

C8, a component of the complement system consists of three polypeptides C8A, C8B and C8G and takes part in the formation of Membrane Attack Complex (MAC). Patients with C8 deficiency are exposed to several bacteria infections. C8G, a member of the lipocalin family and calycin superfamily, is a secreted protein that can bind retinol. C8G is created in the liver, monocytes and fibroblast and has a role in clearing pathogens from an infected host.