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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.

Alpha 1 ACT is an early-stage acute-phase plasma protein and a serpin that preferentially inactivates chymotrypsin, cathepsin G, and chymase. Alpha-1-ACT, a serine protease inhibitor, is tightly associated with amyloid plaques in Alzheimer's disease (AD) and in normal aged human and monkey brain.
Regulation of the serine proteases and serine protease inhibitors plays an important role in neuromuscular differentiation. Prostate specific antigen (PSA), a chymotrypsin-like serine protease, is predominantly complexed to Alpha-1-ACT.

OLR1 is a type II membrane protein which belongs to the C-type lectin family and performs as a cell-surface receptor for Ox-LDL. Ox-LDL has a part in early ather-osclerosis, which includes the transformation of monocyte-derived macro-phages to foam cells in atherosclerotic lesions. In addition, OLR1 protein triggers the activation of the NF?B signal transduction pathway.

Intein is a section of a protein which can remove itself and return the remaining segment with a peptide bond. In addition, Inteins hold an endonuclease domain which takes part in Intein proliferation. Actually, various genes have unrelated intein-coding segments inserted at altered positions and they were found in all three domains of life (eukaryotes, bacteria, and archaea) and in viruses.

Adiponectin is a protein exclusively secreted from adipose tissue. In the circulation, adiponectin is present as three different oligomeric complexes, including the high molecular weight (HMW), the middle molecular weight (MMW, also called hexamer) and low molecular weigh (LMW, also called trimer) forms. Different oligomeric complex of adiponectin activates different signaling pathways and exerts distinct functions.

GTP Cyclohydrolase I Feedback Regulator, also known as GCHFR, is a Protein coding gene which includes a homodimer. GCHFR binds and mediates tetrahydrobiopterin inhibition of GTP cyclohydrolase I. GCHFR also regulates phenylalanine metabolism in the liver and in the production of biogenic amine neurotransmitters and nitric oxide.

Platelet factor-4 is a 70-amino acid protein that is released from the alpha-granules of activated platelets.PF4’s major physiologic role appears to be neutralization of 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. Furthermore, it is used as an inhibitor in the angiogenesis during tumor therapy.

Prolactin is a lactogenic hormone secreted by the adenohypophysis .Besides its major action on lactation, in some species prolactin exerts effects on reproduction, maternal behavior, fat metabolism, immunomodulation and osmoregulation.Prolactin has been shown also to have cytokine-like activities and to have important immunoregulatory activities. It contributes to the development of lymphoid tissues and the maintenance of physiological immune function and also modulates a variety of T-cell immune responses. Prolactin has been reported to activate cellular proliferation in nonreproductive tissue, such as liver, spleen, and thymus. It induces significant proliferation in aortic smooth muscle cells and also enhances proliferation of these cells induced by PDGF . Prolactin also appears to be directly mitogenic for pancreatic beta cells. Prolactin is also mitogenic for cultured astrocytes.

Nonspecific lipid transfer proteins (nsLTPs) are expressed throughout the plant tissues. They have a typical cysteine pattern forming disulfide bonds and are important allergens in fruits and tree nuts. Sensitization to nsLTP Cor a 8.0101 is more frequent among patients with hazelnut allergy in the Mediterranean area than the northern parts of Europe.

Leukocyte Cell-Derived Chemotaxin 2 (LECT2) functions as a chemotactic factor to neutrophils. LECT2 stimulates the proliferation of chondrocytes and osteoblasts. LECT2 is strongly expressed in the liver and weakly in the testis. LECT2 is a secreted, 16kDa protein which serves as a chemotactic factor to neutrophils and stimulates the growth of chondrocytes and osteoblasts. LECT2 protein has a high sequence similarity to the chondromodulin repeat regions of the chicken myb-induced myeloid 1 protein. A polymorphism in the LECT2 gene is linked with rheumatoid arthritis.

Lamin-A is a major component of the nuclear lamina, a dynamic meshwork located just under the nuclear envelope and it is encoded by lamin A/C gene (LMNA).
Lamin-A is synthesized as Prelamin A, a longer precursor that in vivo goes through a serial post-translational modifications that lead to mature Lamin A.
Diverse mutations in the Lamin A/C gene are associated with different diseases that are collectively called laminophaties, including Emery-Dreifuss muscular dystrophy, familiar partial lipodystrophy, limb girdle muscular dystrophy, dilated cardiomyopathy, Charcot-Marie-Tooth disease, and Hutchinson-Gilford progeria syndrome.

Prolactin is a neuroendocrine hormone synthesized primarily by the pituitary gland but also a variety of other cell types including the placenta, brain and uterus. Its primary function is to promote and maintain lactation but has also been shown to have a role in breast cancer development, regulation of reproductive function and immunoregulation.

Tumor necrosis factor is a cytokine involved in systemic inflammation and is a member of a group of cytokines that all stimulate the acute phase reaction. TNF is mainly secreted by macrophages.
TNF causes apoptotic cell death, cellular proliferation, differentiation, inflammation, tumorigenesis and viral replication, TNF is also involved in lipid metabolism, and coagulation. TNF's primary role is in the regulation of immune cells.
Dysregulation and, in particular, overproduction of TNF have been implicated in a variety of human diseases- autoimmune diseases, INS resistance, and cancer.

Prolactin is a lactogenic hormone secreted by the adenohypophysis .Besides its major action on lactation, in some species prolactin exerts effects on reproduction, maternal behavior, fat metabolism, immunomodulation and osmoregulation.Prolactin has been shown also to have cytokine-like activities and to have important immunoregulatory activities. It contributes to the development of lymphoid tissues and the maintenance of physiological immune function and also modulates a variety of T-cell immune responses. Prolactin has been reported to activate cellular proliferation in nonreproductive tissue, such as liver, spleen, and thymus. It induces significant proliferation in aortic smooth muscle cells and also enhances proliferation of these cells induced by PDGF . Prolactin also appears to be directly mitogenic for pancreatic beta cells. Prolactin is also mitogenic for cultured astrocytes.

Antigen 85A is a member of the antigen 85 complex (Antigen 85A, B, C). The enzymes of the antigen 85 complex have mycolyltransferase activity and catalyze the synthesis of the very rich glycolipid of the mycobacterial cell wall, the cord factor (trehalose 6,6'-dimycolate, TDM). The cord factor is vital for the integrity of the mycobacterial cell wall and pathogenesis of the bacillus. TDM is synthesized from two molecules of trehalose-6'-monomycolate (TMM) by Antigen 85A.

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.

Avidin is a tetrameric protein of 4 identical subunits (homotetramer) each of which can bind to biotin with a high degree of affinity and specificity. Avidin molecular weight in its tetrameric form is estimated to be between 66-69 kDa. Avidin is produced in the oviducts of birds, reptiles and amphibians and is subsequently deposited in the whites of their eggs. In the chicken egg white, avidin makes up roughly 0.05% of total protein (approximately 1.8 mg per egg). 10% of Avidin’s molecular weight is ascribed to carbohydrate content which is composed of four to five mannose and three N-acetylglucosamine residues. Avidin has at least three distinctive oligosaccharide structural type which are similar in structure and composition. The dissociation constant (KD) of avidin is approximately 10-15M, making it one of the strongest known non-covalent bonds.

Adiponectin is an adipocyte specific secreted protein that circulates in the plasma. It is induced during adipocyte differentiation and its secretion is stimulated by insulin. Mouse adiponectin shares about 83% amino acid identity with that human. Adiponectin plays a role in various physiological processes such as energy homeostasis and obesity. Adiponectin is reduced in obese humans, and decreased level is associated with insulin resistance and hyperinsulinemia.

Eukaryotic Translation Initiation Factor 3F, also known as EIF3F belongs to the eIF-3 subunit F family. EIF3F is a component of the eukaryotic translation initiation factor 3 (eIF-3) complex, which isessential for several steps in the initiation of protein synthesis. The eIF-3 complex associates with the 40S ribosomeand facilitates the recruitment of eIF-1, eIF-1A, eIF 2: GTP: methionyl-tRNAi and eIF-5 to form the 43S preinitiationcomplex (43S PIC). In addition, the eIF-3 complex stimulates mRNA recruitment to the 43S PIC and scanning of the mRNA forAUG recognition. The eIF-3 complex is also necessary for disassembly and recycling of post termination ribosomalcomplexes and subsequently prevents premature union of the 40S and 60S ribosomal subunits prior to initiation. Among the diseases associated with EIF3F are intrahepatic cholangiocarcinoma, and cholangiocarcinoma.

Connective Tissue Growth Factor belongs to the CCN family of proteins. The CCN family presently consists of six members in human also known as: Cyr61 (Cystein rich 61), CTGF (Connective Tissue Growth Factor), Nov (Nephroblastoma Overexpressed gene), WISP-1, 2 and 3 (Wnt-1 Induced Secreted Proteins). The CCN genes encode secreted proteins associated with the Extracellular Matrix (ECM) and cell membrane.
CCN proteins are matricellular proteins which are involved in the regulation of various cellular functions including: proliferation, differentiation, survival, adhesion and migration. They are expressed in derivatives of the three embryonic sheets and are implicated in the development of kidney, nervous system, muscle, bone marrow, cartilage and bone. During adulthood, they are implicated in wound healing, bone fracture repair, and pathologies such as: fibrosis, vascular ailments and tumorigenesis.
Full length secreted CCN proteins can show an antiproliferative activity, whereas truncated isoforms are likely to stimulate proliferation and behave as oncogenes.
The full length protein consists of four modules: Module I shares partial identity with the N-terminal part of the Insulin-like Growth Factor Binding Proteins (IGFBPs).
Module II includes a stretch of 70amino acid residues – which shares sequence identity with the Von Willebrand Factor Type C repeat (VWC).
Module III contains sequences sharing identity with the Thrombospondin type 1 repeat (TSP1) (WSXCSXXCG), which is thought to be implicated in the binding of sulfated glycoconjugates and to be important for cell adhesion.
Module IV, also designated CT, is encoded by exon5. It is the leasts conserved one of the four domains at the level of nucleotide sequence, but it appears to be critical for several of the biological functions attributed to the CCN proteins. Module IV resembles the CT domain of several extracellular protein including, Von Willebrand's factor and mucins. Sequence similarities to heparin-binding motifs are also found within this domain.
Proteolysis of the secreted full-length CCN proteins that has been reported in the case of CCN2 and CCN3 might result in the production of CCN-derived peptides with high affinity for ligands that full-length CNN proteins bind only poorly. Amino-truncated CCN2 isoforms were biologically active whereas no specific biological activity has been attributed to the truncated CCN3. Although the molecular processes underlying the production of these secreted isoforms is presently unknown, it is important to note that proteolysis occur at the same amino acid residues in both CCN2 and CCN3. An elevated expression of CCN2 has also been detected by Northern blotting in human invasive mammary ductal carcinomas, dermatofibromas, pyogenic granuloma, endothelial cells of angiolipomas and angioleiomyomas, and in pancreatic tumors. A study performed with chondrosarcomas representative of various histological grades established that CCN2 expression was closely correlated with increasing levels of malignancy.
In agreement with CCN2 playing a role in brain tumor angiogenesis, immunocytochemistry studies indicated that both glioblastoma tumor cells and proliferating endothelial cells stained positive for CCN2. In astrocytomas, CCN2 expression was particularly elevated in high grade tumors, with a marked effect of CCN2 on cell proliferation. Downregulation of CCN2 expression in these cells was associated with a growth arrest at the G1/S transition while over-expression of CCN2 induced a two-fold increase of the number of cells in the G1 phase. Gene profiling analysis allowed to identify a set of about 50 genes whose expression might account for the proliferative activity of CCN2 in these cells.
CCN2 was seen in a higher proportion of mononuclear cells of patients with acute lymphoblastic leukemia.

Beta-lactamase is a type of enzyme (EC 3.5.2.6) produced by some bacteria that is responsible for their resistance to beta-lactam antibiotics like penicillins, cephalosporins, cephamycins and carbapenems. These antibiotics have a common element in their molecular structure: a four-atom ring known as a beta-lactam. The lactamase enzyme breaks that ring open, deactivating the molecule's antibacterial properties.

HB-EGF is an EGF related growth factor which signals via the EGF receptor, and stimulates the proliferation of SMC (smooth muscle cells), fibroblasts, epithelial cells and keratinocytes. HB-EGF is expressed in various cell types and tissues, including vascular endothelial cells and SMC, macrophages, skeletal muscle, keratinocytes and particular tumor cells. HB-EGF’s ability to explicitly bind HPR sulfate proteoglycans is dissimilar from other EGF-like molecules, and might be related to the enhanced mitogenic activity, relative to EGF, that HB-EGF exerts on smooth muscle cells.