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Aspartylglucosaminidase, also known as AGA, takes part in the catabolism of Nlinked oligosaccharides of glycoproteins. AGA is a protein coding gene which cleaves asparagine from N-acetylglucosamines in the lysosomal breakdown of glycoproteins.

Streptolysin-O is a sulfhydryl-activated toxin which causes cytolysis by forming pores in cholesterol containing host membranes. After binding to target membranes, the Streptolysin-O protein undergoes a major conformation change, leading to its insertion in the host membrane and creation of an oligomeric pore complex. Cholesterol may be needed for binding to host membranes, membrane insertion and pore formation. Streptolysin-O can be reversibly inactivated by oxidation.

Transferrin is the iron-transport protein of vertebrate serum and donates iron to cells through interaction with a specific membrane receptor, CD71. Transferrin appears to be indispensable for most cells growing in tissue culture.
It is referred to frequently as a growth factor because, in analogy to other growth factor-receptor interactions, proliferating cells express high numbers of transferrin receptors, and the binding of transferrin to their receptors is needed for cells to initiate and maintain their DNA synthesis. Apart from its role as an iron transport protein transferrin acts as a cytokine and has functions that may not be related to its iron-carrying capacity.
Bovine Transferrin is a crucial component for the cultivation of mammalian cells in- vitro. Bovine Transferrin is Critical for long-term cells growth in-vitro. Bovine Transferrin is used as detoxificant in media by binding contaminating metal ions. Bovine Transferrin is often used as a nutrient in fermentation media for recombinant protein and biopharmaceutical production. Additional common uses of Bovine Transferrin are Molecular weight, Affinity purification of anti-human transferrin antibodies and also as receptor mediated transfection of molecules such as DNA, into cells.

Signal-Regulatory Protein Alpha, SIRPA belongs to the signal-regulatory-protein (SIRP) family, as well as theimmunoglobulin super family. The members of the SIRP family are receptor-type transmembrane glycoproteins which areinvolved in the negative regulation of receptor tyrosine kinase-coupled signaling processes. SIRPA can bephosphorylated by tyrosine kinases. The phospho-tyrosine residues of this PTP have been shown to recruit SH2domain containing tyrosine phosphatases (PTP), and perform as substrates of PTPs. SIRPA take part insignal transduction mediated by a variety of growth factor receptors. CD47 has been shown to be a ligand for SIRPA.

HBsAg is the surface antigenof the Hepatitis-B-Virus (HBV). The capsidof a virus has different surface proteins from the rest of the virus. The antigen is a protein that binds specifically on one of these surface proteins. It is commonly referred to as the Australian Antigen.

Recombinant Human Sonic Hedgehog is part of a small group of secreted proteins that are vital for development in both vertebrates and invertebrates. 3 mammalian hedgehog genes (sonic, desert, Indian) share about 60% homology. The Human Sonic Hedgehog is 99% homologous to the mouse gene. Sonic HedgeHog is a protein that is vital in guding the early embryo. It has been associated as the major inductive signal in patterning of the ventral neural tube, the anterior-posterior limb axis, and the ventral somites. Sonic HedgeHog binds to the patched receptor, which functions in association with smoothened, to activate the transcription of target genes. In the absence of sonic HedgeHog, patched receptor represses the constitutive signaling activity of smoothened. Sonic HedgeHog also regulates another factor, the gli oncogene. Sonic HedgeHog intercellular signal is essential for a various patterning events during development: signal produced by the notochord that induces ventral cell fate in the neural tube and somites, and the polarizing signal for patterning of the anterior-posterior axis of the developing limb bud. Sonic HedgeHog exhibits both floor plate- and motor neuron-inducing activity. Mutations in a long-range Sonic HedgeHog enhancer located in an intron of the limb region 1 gene result in preaxial polydactyly.

Sialic acid-binding Ig-like lectin 6 isoform 1 (SIGLEC6) is a member of immunoglobulin superfamily and SIGLEC (sialic acid binding Ig-like lectin) family. SIGLEC6 mediates sialic-acid dependent binding to cells and binds to alpha-2, 6-linked sialic acid. The SIGLEC6 protein localizes in numerous compartments such as membrane fraction, extracellular region and so on. The SIGLEC6 receptor binds sialyl-TN glycans and leptin. Placental expression SIGLEC6 is upregulated in preeclampsia.

Sialic acid-binding Ig-like lectin 7 isoform 1, also known as SIGLEC7, is a newly discovered family of sialic acid-binding lectins of the immunoglobulin (Ig) superfamily. The extracellular portion has two Ig-like domains, with the amino-terminal V-set Ig domain containing amino acid residues which known to be implicated in sialic acid recognition by other Siglecs. The combination of an extracellular sialic acid binding site and an intracellular ITIM motif proposes that SIGLEC7 is involved in trans-membrane regulatory signaling reactions. Furthermore, on the cell surface SIGLEC7 exists as a monomer and is expressed on natural killer cells.

Signal-Regulatory Protein Gamma (SIRPG) belongs to the signal-regulatory protein (SIRP) family whose members are receptor-type transmembrane glycoproteins which negatively regulate the receptor tyrosine kinase-coupled signaling processes. SIRPG is also a part of the immunoglobulin superfamily.

Podoplanin is a small mucin-like type-1 transmembrane protein, typically expressed in various specialized cell types throughout the body. Podoplanin is a type-I integral membrane glycoprotein with diverse distribution in human tissues. PDPN physiological function is related to its mucin-type character. The homologous protein in other species has been described as a differentiation antigen and influenza-virus receptor.
PDPN is expressed in lymphatic progenitor cells and afterwards during mouse development in lymphatic endothelial cells. Podoplanin is a specific marker for lymph vessel endothelial cells. Over-expression of podoplanin significantly elevates endothelial cell adhesion, migration, and tube formation. Inhibition of Podoplanin expression decreases cell adhesion in human dermal lymphatic endothelial cells. Podoplanin is used as a specific marker for lymphatic endothelium in histopathology.
Podoplanin expression is increased in nearly all human colon, rectum, and small intestine tumors. AGGRUS may serve as a diagnostic marker that distinguishes seminomas, the majority of which over express the protein, from embryonal carcinoma in testicular germ cell tumors.

Alpha 1-microglobulin (A1M) is a lipocalin superfamily member (kernal lipocalins). A1M is a low molecular weight protein component of plasma. A1M is distributed in plasma and extravascular compartments of all organs. Alpha-1 Microglobulin is found in mammals, birds, amphibians and fish. The primary sites of A1M synthesis are the liver and the kidney. Around the opening of the lipocalin pocket three lysyl residues are situated; those residues carry yellow-brown modification derived from the binding and degradation of heme and kynurenin (a tryptophan metabolite). A1-Microglobulin’s reductase and dehydrogenase have broad biological substrate specificity properties due to its’ free cysteine side-chain which is located in a flexible loop. Alpha-1-microglobulin is glycosylated by three separate carbohydrate chains: two complex carbohydrates which are N-linked to asparagines at residues 17 and 96, and the other simple carbohydrate which is O-linked to threonine at position 5. The carbohydrates comprise 22% of the total molecular mass of the protein. The glycosylation varies between species.
A1M exists in two forms- a free form and complexed to other macromolecules: in humans- complexed to immunoglobulin A (IgA), in rat- complexed to alpha-1-inhibitor-3. Free A1M is exceptionally heterogeneous in charge (therefore also known as protein HC), and is found tightly linked to a chromophore. The free Alpha-1-microglobulin is a monomeric protein composed of one 188 residue polypeptide and contains three cysteines, two of which (residues 75 and 173) form a conserved intra-molecular disulphide link. The chromophoric group is covalently bound to the free cysteine residue at position 34. A1M binds retinol as a major ligand, but this is probably distinct from its covalent chromophore.
Half of all human plasma A1M (approximately 0.03mg/ml) forms a 1:1 complex with about 5% of plasma immunoglobulin A. The resulting macromolecular complexes’ molecular weight is 200000, and a plasma concentration of 0.3mg/ml. The complex can exhibit both antibody activity and affect many of the biological actions of free Alpha-1-microglobulin.
Alpha-1-microglobulin was first discovered in pathological human urine.
It was suggested that A1M might be involved in tissue defense against reactive oxygen species, oxidation by heme and kynurenin. Evidence also suggests that A1M functions in the regulation of the immune system. Other functions include inhibition of stimulation of cultured lymphocytes by protein antigens; induction of cell division of lymphocytes, a mitogenic effect that can either be enhanced or inhibited by the action of other plasma components; inhibition of neutrophil granulocyte migration in vitro; and inhibition of chemotaxis.

Sialic Acid Binding Ig Like Lectin 9 (SIGLEC9) is a member of the sialic acid-binding Ig-like lectin family, which is a part of the immunoglobulin superfamily expressed mostly on human blood leukocytes. SIGLEC9 is a Putative adhesion molecule which is expressed in bone marrow, placenta, spleen, and fetal liver. SIGLEC9 is also a part of the recently characterized CD33-related Siglec family of sialic acid binding protein.

Legumain, also known as LGMN is a lysosomal cysteine protease which is found in all mouse tissues, however it was mainly abundant in the kidney as well as placenta. LGMN plays an essential role in the endosomal/lysosomal degradation system as the Legumain deficiency causes the accumulation of pro cathepsins B, H & L, another group of lysosomal cysteine proteases. Furthermore, over expression of LGMN in tumors is important for invasion/metastasis.

SEPT5 is a member of the septin gene family of nucleotide binding proteins which were initially defined in yeast as cell division cycle regulatory proteins. Septins are extremely conserved in yeast, Drosophila, and mouse and seem to regulate cytoskeletal organization. Interference of septin function disrupts cytokinesis and results in high multinucleate or polyploid cells.

Btc is a potent mitogen for retinal pigment epithelial cells and vascular smooth muscle cells. The effects of betacellulin are probably mediated by the egf receptor and other related receptors.

XCL1 is a small cytokine belongs to the XC chemokine family that is also known as lymphotactin. XCL1 is found in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

Sarcoglycan Beta, also known as SGCB, is a part of the sarcoglycan family. SGCB belongs to the sarcoglycan complex which is a subcomplex of the dystrophin-glycoprotein complex that connects between the F-actin cytoskeleton and the extracellular matrix.

Recombinant Hirudin is a potent thrombin inhibitor originally derived from the medicinal leech. Hirudin acts directly on thrombin rather than through other clotting factors. The mechanism of Hirudin-thrombin appears to be unique. The conversion of fibrinogen into fibrin by the serine protease enzyme thrombin is a major event in the final stages of blood coagulation. In the final stages of coagulation prothrombinase converts prothrombin into thrombin. Fibrin is subsequently cross linked by factor XIII to form a blood clot. The primary inhibitor of thrombin in normal blood circulation is antithrombin III. The anticoagulatant activity of hirudin is derived from its ability to inhibit the pro-coagulant activity of thrombin (similar to antithrombin III activity). Hirudin is the strongest natural inhibitor of thrombin. Hirudin binds to and inhibits only the activity of thrombin forms with a specific activity on fibrinogen contrasting to antithrombin III activity. Therefore, hirudin has a thrombolytic activity since it prevents or dissolves the formation of clots and thrombi. Hirudin also has therapeutic significance in blood coagulation disorders, in the treatment of skin hematomas and of superficial varicose veins. Hirudin does not hinder with the biological activity of other serum proteins and can also act on complexed thrombin, thus having an advantage over more common anticoagulants and thrombolytics. It is complicated to extract large quantities of hirudin from natural sources; therefore a method for producing and purifying hirudin using recombinant biotechnology has been developed.

Selenoprotein W 1, also known as SEPW1 is a selenoprotein, which has a selenocysteine (Sec) residue at its active site. The selenocysteine is encoded through the UGA codon which normally signals translation termination. The 3' UTR of selenoprotein genes share a common stem-loop structure, the sec insertion sequence (SECIS), which is essential for the recognition of UGA as a Sec codon instead of as a stop signal. SEPW1 shows highest expression in skeletal muscle and heart, and also involved in oxidation-reduction reactions.

Oncomodulin is a member of the superfamily of calmodulin proteins, otherwise known as the EF-hand proteins. It is a high-affinity calcium ion-binding protein. Oncomodulin is an oncodevelopmental protein which is found in early embryonic cells in the placenta and also in tumors.

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).

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).

E-selectin which is also called Endothelial leukocyte adhesion molecule 1, ELAM1, ELAM belongs to a family of divalent cation-dependent carbohydrate-binding glycoproteins or adhesion molecules. Eselectin is expressed on the surface of endothelial cells and mediates the interaction of leukocytes and platelets with endothelial cells during an inflammatory response. E-selectin is present in single copy in the human genome and contains 14 exons spanning about 13 kb of DNA.