Search results

Galectins are a family of animal lectins with an affinity for beta-galactosides. This family has at least 14 identified members. Galectins share similarities in the CRD (the carbohydrate recognition domain). Galectins are synthesized as cytosolic proteins. Though localized principally in the cytoplasm and lacking a classical signal peptide, galectins can also be stimulated to secretion by non-classical pathways or alternatively targeted to the nucleus. Galectins are involved in modulating cell-cell and cell-matrix interactions. Galectin-8 is a tandem-repeat-type member of the galectin family, consisting of 2 CRDs attached by a linker peptide. Galectin-8 is greatly expressed in lung carcinomas, a number of forms of prostate carcinomas, in addition to other tumor cells. Galectin-8 attaches to a subset of cell surface integrins to modulate ECM-integrin interactions. Once immobilized, Galectin-8 promotes cell adhesion by ligation and clustering of cell surface integrin receptors. On the other hand, as a soluble ligand, Galectin-8 can inhibit cell adhesion.

Cystatin-SN (CST1) belongs to the type 2 salivary cystatin family found in a variety of fluids and secretions, including plasma, tears, and saliva. The cystatin superfamily includes proteins which contain multiple cystatin-like sequences. Some of the members are active cysteine protease inhibitors, whereas others have lost or possibly never developed this inhibitory activity. CST1 is up-regulated in cancerous lesions of gastric cancer tissues compared to noncancerous regions, in addition clinicopathological analysis revealed a significant correlation between high expression of CST1.

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.

Eledoisin is an undecapeptide formed in the venom gland of several species of octopuses and is used as a vasodilator and a contraction agent of extravascular smooth muscle.

Cystatins are a superfamily of cysteine proteinase inhibitors found in both plants and animals. They comprise a group of proteinase inhibitors, widely distributed in tissues and body fluids, and form tight complexes with cysteine proteases such as cathepsin B, H, L and S. Cystatin C, a secreted molecule of this family, is of interest from biochemical, medicine and evolutionary points of view. Cystatin C, with molecular weight of 13260 Da, is composed of 120 amino acids, lacks carbohydrate and has two disulfide bridges located near the carboxyl terminus. Cystatin C is increased in patients with malignant diseases, and is related to the insufficiency of renal function and appears to be a better marker than creatinine. On the other hand, low levels of cystatin C involve cause the breakdown of the elastic laminae and, subsequently, the atherosclerosis and abdominal aortic aneurysm.

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.

Dickkopf-related protein 3 (DKK3) belongs to the DKK protein family including Dkk-1, 2, 3 and -4. DKK3 is a 350 amino acid secreted glycoprotein which is comprised of an N-terminal signal peptide and 2 conserved cysteine-rich domains that are separated by a 12 amino acid linker region. DKK3 is involved in embryonic development through its inhibition of the WNT signaling pathway. DKK3 gene expression is decreased in a variety of cancer cell lines and it may act as a tumor suppressor gene.

Profilin1 (PFN1) is a ubiquitous actin monomer-binding protein which is a member of the profilin family. PFN1 significantly boosts skin wound healing in-vitro and in-vivo which may be mediated by purinergic receptors. PFN1 is also active in endothelial cell migration and vessel sprouting. PFN1 is thought to control actin polymerization in response to extracellular signals. PFN1 binds to actin and affects the formation of the cytoskeleton. In addition, PFN1 has an important role in the regulation of epithelial cell-cell adhesion. At high concentrations, profilin averts the polymerization of actin, while at low concentrations it enhances the polymerization. PFN1 gene deletion is linked to Miller-Dieker syndrome.

Cystatin E/M or CST6 is part of the cystatin type 2 family. Part of the cystatin type 2 family members can act as cysteine protease inhibitors, whereas cystatin E/M regulates cathepsin B inhibitors and not cathepsin C. cystatin E/M is a protein the when secreted, has an effect on osteogenesis and bone resorption, insulin regulation, response to systemic inflammation & hepatocyte growth factor receptors.

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.

Ferritin is a fairly large, iron-storage heteropolymeric protein composed of 2 subunit types, light Ferritin & heavy Ferritin polypeptides, which is expressed in most kinds of cells and co-assemble in different proportion in a tissue-specific manner. Ferritin is composed of 24 self-assembled polypeptide subunits of the heavy and light ferritin chains and is characterized by the capacity to remove Fe (II) from solution in the presence of oxygen.
Ferritin light polypeptide protein is the main intracellular iron storage protein in prokaryotes and eukaryotes. Variation in ferritin subunit composition influence the rates of iron uptake and release in various tissues. A key function of ferritin is the storage of iron in a soluble and nontoxic state. Defects in this light chain ferritin gene are associated with several neurodegenerative diseases and hyper ferrit anemia-cataract syndrome.
Ferritin stores iron in a soluble, nontoxic, readily accessible form. Ferritin is needed for iron homeostasis. Iron is taken up in the ferrous form and deposited as ferric hydroxides after it has been oxidized.

Latexin enzyme is a carboxypeptidase A inhibitor that is highly expressed in the heart, prostate, ovary, kidney, pancrease, brain and colon. Latexin has no noticeable sequence resemblance with plant and parasite inhibitors, however it is related to a human putative tumor suppressor protein, TIG1. Latexin is down-regulated in the presenilin-1-deficient mouse brain, thus putatively playing a role in Alzheimer's disease.

Galectin-3 mediates with the alpha-3, beta-1 integrin the stimulation by cspg4 of endothelial cells migration. Galectin-3 plays an necessary part during the acquisition of vasculogenic mimicry and angiogenic properties associated with melanoma progression. LGALS3 overexpression is highly expressed in early stages of papillary carcinoma, and its expression intensity declines during tumor progression. Serum levels of LGALS3 are high in patients with thyroid malignancy but there is considerable overlap in serum LGALS3 concentrations between those with benign and malignant nodular thyroid disease. LGLAS3 takes part as an immune regulator to inhibit T-cell immune responses and promote tumor growth, as a result providing a new mechanism for tumor immune tolerance.

OSTF1 is an intracellular protein produced by osteoclasts that induces bone resorption, via signaling cascade which results in the secretion of factors enhancing osteoclast formation and activity.

Testican-3 (Spock3) is a nervous system-expressed heparan sulfate proteoglycan belonging to a subgroup of the BM-40/SPARC/osteonectin family, whose role of in brain development is unclear. Spock3 inhibits the processing of pro-matrix metalloproteinase 2(MMP-2) by MT1-MMP and MT3-MMP. Spock3 is mostly confined to the developmental stage of the brain.

LGALS2 is a soluble beta-galactoside binding lectin that controls cell-to-cell adhesion and cell-to-extracellular matrix interactions and takes part in tumor progression, pre-mRNA splicing and apoptosis. LGALS2 induces apoptosis in activated T cells and binds to the cytokine lymphotoxin-alpha (LTA) with threat of myocardial infarction.

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 -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.

TREM2 is a membrane protein that forms a receptor signaling complex with TYROBP. TREM2 may be involved in chronic inflammation by triggering the production of constitutive inflammatory cytokines. Defects in the TREM2 gene are a source of polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy (PLOSL).

Dynactin 6, also known as DCTN6 is a member of the dynactin subunits 5/6 family. DCTN6 includes an RGD (Arg-Gly-Asp) motif in the N-terminal region, which confers adhesive properties to macromolecular proteins such as fibronectin. DCTN6 has a high degree of sequence resemblance with the mouse homolog, which has been found to participate in mitochondrial biogenesis. Moreover, the precise biological function of DCTN6 is unknown.

TIPIN is a member of the CSM3 family. TIPIN protein is essential for normal advancement of S-phase and vital for cell existence after DNA damage or replication stress. TIPIN is specifically necessary for the ATR - CHEK1 pathway in the replication checkpoint induced by ultraviolet light.

CAMP belongs to the antimicrobial peptide family, contains highly conserved N-terminal signal peptide, a cathelin domain and a structurally variable cationic antimicrobial peptide that produced by extracellular proteolysis from the C-terminus. CAMP has numerous functions besides the antimicrobial activity such as: cell chemotaxis, immune mediator induction and inflammatory response regulation.