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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.
Human Transferrin is a crucial component for the cultivation of mammalian cells in-vitro. Human Transferrin is Critical for long-term cells growth in-vitro. Human Transferrin is used as detoxificant in media by binding contaminating metal ions. Human Transferrin is often used as a nutrient in fermentation media for recombinant protein and biopharmaceutical production. Additional common uses of Human Transferrin areMolecular weight, Affinity purification of anti-human transferrin antibodies and also as receptor mediated transfection of molecules such as DNA, into cells.

AIMP1 (EMPA2 or p43) is a cytokine that is specifically induced by apoptosis, and it is involved in the control of angiogenesis, inflammation, and wound healing. The release of the AIMP1 cytokine renders the tumor-associated vasculature sensitive to tumor necrosis factor. Furthermore, AIMP1 is involved in the stimulation of inflammatory responses after proteolytic cleavage in tumor cells.

MS4A1 is an activated-glycosylated phosphoprotein expressed on the surface of all B-cells. The expression begins at the pro-B phase and until maturity the concentration increases in order to allow optimal B-cell immune response, specifically against T-independent antigens. MS4A1 takes part in the microenvironmental interactions of B cells and also in the regulation of B-cell activation and proliferation. MS4A1 also plays a role as a calcium channel in the cell membrane.

Adaptor-related protein complex 1 associated regulatory protein (AP1AR) is essential for AP-1 dependent transport between the trans-Golgi network and endosomes. AP1AR regulates the membrane association of AP1G1/Gamma1-adaptin which is one of the subunits of the AP-1 adapter complex. AP1AR plays a role as effector of AP-1 in calcium-induced endo-lysosome secretion. The interaction with AP1G1/Gamma1-adaptin attenuates the release of the AP-1 complex from membranes.

Syntaxin is membrane integrated Q-SNARE protein participating in exocytosis. Syntaxin is composed of an N-terminal regulatory domain (Habc), a SNARE domain (known as H3), and a single C-terminal transmembrane domain. The SNARE (H3) domain binds to both synaptobrevin and SNAP-25 forming the core SNARE complex. Synaptic vesicles store neurotransmitters that are released during calcium-regulated exocytosis. The specificity of neurotransmitter release requires the localization of both synaptic vesicles and calcium channels to the presynaptic active zone. Syntaxins function in this vesicle fusion process. Syntaxins also serve as a substrate for botulinum neurotoxin type C, a metalloprotease that blocks exocytosis and has high affinity for a molecular complex that includes the alpha-latrotoxin receptor which produces exocytosis.

Fc fragment of IgE, high affinity I, receptor for; alpha polypeptide (FCER1A) binds to the Fc region of immunoglobulins epsilon. FCER1A is a high affinity receptor. In addition FCER1A is responsible for starting the allergic response. Binding of allergen to receptor-bound IgE leads to cell activation and the release of mediators such as histamine which is responsible for the manifestations of allergy. This receptor is contains of an alpha subunit, a beta subunit, and two gamma subunits. FCER1A stands for the alpha subunit. Among the diseases associated with FCER1A are mast-cell leukemia, and allergic asthma.

Interleukin-5 receptor subunit alpha (Il5ra) regulates the development and function of eosinophils. The Il5ra protein is a therapeutic target for hypereosinophilic diseases including allergic inflammations and asthma. Oct2 enhances antibody-secreting cell differentiation via regulation of Il5ra chain expression on activated B cells.

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.

Serine racemase (SRR) is an enzyme which generates D-serine from L-serine. D-serine functions as a neuronal signaling molecule by activating NMDA receptors in the brain. Mammalian SRR is a pyridoxal 5'-phosphate dependent enzyme which catalyzes both the racemization of L-serine to D-serine and also the elimination of water from L-serine, producing pyruvate and ammonia. The SRR enzyme is physiologically stimulated by divalent cations (e.g., magnesium) and is allosterically activated by the magnesium/ATP complex.

Adhesion Molecule with Ig-Like Domain 2, also known as AMIGO2 is a member of the leucine-rich repeat family. AMIGO2 arbitrates homophilic in addition to heterophilic cell-cell interaction with AMIGO1 or AMIGO3. Furthermore, AMIGO2 contributes to signal transduction via its intracellular domain and is also essential for tumorigenesis of a subset of gastric adenocarcinomas.

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 modulesModule 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.

Leptin is a protein hormone. It is mainly produced in adipose cells that regulate energy homeostasis by restraining hunger. Leptin ties to nuclear receptors in the hypothalamus (arcuate nucleus). Similar to insulin resistance in type II diabetes, in obesity there is a decrease in the sensitivity towards leptin, ending in a failure to identify satiety, even in high levels of energy stores or leptin itself. Full-length cDNA encoding 2 leptin sequences (tLepA and tLepB) and 1 leptin receptor sequence (tLepR) exists in tilapia (Oreochromis niloticus). The full-length cDNA of tLepR is 3423 bp, encoding a protein of 1140 amino acid which contained all functionally important domains conserved among vertebrate leptin receptors. The cDNAs of tLepA and tLepB are 486 bp and 459 bp in length, encoding proteins of 161 aa and 152 aa, respectively. The three-dimensional structures of tLepA and tLepB demonstrates strong conservation of tertiary structure with that of human leptin comprised of 4 helixes.

MNDA plays a role as a transcriptional activator/repressor in the myeloid lineage and in the granulocyte/monocyte cell-specific response. MNDA Stimulates the DNA binding of the transcriptional repressor protein YY1. MNDA is identified only in nuclei of cells of the granulocyte-monocyte lineage.

OAS1 enzyme is a member of the 2’,5’-oligoadenylate synthetase family. OAS1 is induced by interferons and uses adenosine triphosphate in 2’-specific nucleotidyl transfer reactions to synthesize 2’,5’-oligoadenylates(2-5As). These molecules in turn activate latent RNase L resulting in viral RNA degradation and the inhibition of viral replication.
OAS1 may have a role in mediating resistance to virus infection, control of cell growth, differentiation, and apoptosis. OAS1 binds double-stranded RNA and polymerizes ATP into PPP (A2'P5'A)N oligomers, which activate the latent RNase L that, once activated, cleaves single-stranded RNAs.
OAS1 gene mutations are been linked to host susceptibility to viral infection.
OSA1 gene polymorphisms are linked to the outcome of hepatitis C virus infection. Furthermore, OAS1 gene polymorphisms are linked to the susceptibility to severe acute respiratory syndrome.

TEN1 is part of a complex that binds to single-stranded DNA and is necessary in order to protect telomeres from DNA degradation (CST complex). The CST complex binds single-stranded DNA with high affinity in a sequence-independent mode, while isolated subunits bind DNA with low affinity by themselves. Further to telomere protection, the CST complex has most likely a more general part in DNA metabolism at non-telomeric sites.

TRIM21 is a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. The 52 kDa Ro protein is part of the RoSSA ribonucleoprotein, which includes a single polypeptide and one of four small RNA molecules. The RoSSA particle localizes to both the cytoplasm and the nucleus. Ro/SSA interacts with autoantigens in patients with Sjogren syndrome and systemic lupus erythematosus. Ribonucleoprotein particle is composed of a single polypeptide and one of four small RNA molecules. The RoSSA is present in all mammalian cells studied but has no known function. At least 2 isoforms are present in nucleated and red blood cells, and tissue specific differences in Ro/SSA proteins were identified.

C-type lectin domain family 5-member A isoform 1 (CLEC5A) is part of the CTL/CTLD superfamily which carry various functions, for instance cell-cell signaling, cell adhesion, glycoprotein turnover, in addition to their inflammation & immune response abilities. CLEC5A operates as a cell attachment receptor for all 4 serotypes of Dengue virus in addition to Japanese encephalitis virus. CLEC5A binds to the dengue virus and it triggers signaling through the phosphylation of TYROBP, as a result no viral entrance occurs, however this interaction does stimulate proinflammatory cytokine release. CLEC5A preforms as a positive regulator of osteoclastogenesis and also a main regulator of synovial injury & bone erosion for the period of autoimmune joint inflammation.

Aspartoacylase is a homodimer which catalyzes the deacetylation of N-acetylaspartic acid (NAA) (a protein whose hydrolysis is crucial to maintenance of intact white matter) to generate acetate and L-aspartate. Aspartoacylase (ASPA) is expressed in the liver, lung and kidney tissue, as well as in the skeletal muscle and in cerebral white matter. NAA is ample in the brain where hydrolysis by aspartoacylase is believed to aid maintain white matter. In other tissues ASPA functions as a scavenger of NAA from body fluids. ASPA gene mutations cause Canavan disease (CAND or spongy degeneration of the brain).

The Trefoil Factor peptides (TFF1, TFF2 and TFF3) are stable secretory proteins expressed in the gastrointestinal tract (gastric mucosa), and are involved in intestinal mucosal defense and repair. TFF1 is an essential protein for normal differentiation of the antral and pyloric gastric mucosa and functions as a gastric-specific tumor suppressor gene. TFF1 is a stabilizer of the mucous gel overlying the gastrointestinal mucosa that provides a physical barrier against various noxious agents. TFF1 protects the mucosa from isults, stabilizes the mucus layer, & affects healing of the epithelium. TFF1 is commonly expressed in tumors. TFF1 is related with the cell membrane of MCF-7 cells. High levels of TFF1 and TFF2 are found in serum from inflammatory bowel disease.

Translocase of Inner Mitochondrial Membrane 8 Homolog A (TIMM8A) takes part in the import and insertion of hydrophobic membrane proteins from the cytoplasm into the mitochondrial. TIMM8A plays a role as a chaperone-like protein which protects the hydrophobic precursors from aggregation and leads them through the mitochondrial intermembrane space. TIMM8A is essential for the transfer of beta-barrel precursors from the TOM complex to the sorting and assembly machinery (SAM complex) of the outer membrane. Defects in TIMM8A cause Jensen syndrome. TIMM8A and TIMM13, forms a 70 kDa heterohexamer.

GAGE2A is a member of a multigene family expressed in a large variety of tumors while in normal tissues; expression is limited to germ cells. These genes organized in clustered repeats, have a high degree of predicted sequence identity, however differ by scattered single nucleotide change. Their sequences have either the antigenic peptide YRPRPRRY or YYWPRPRRY which is recognized by cytotoxic T-cells.

Vesicle-Associated Membrane Protein 7 (VAMP7) is a member of the synaptobrevin family. VAMP7 is a transmembrane protein, which is a member of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) family. VAMP7 is involved in the targeting and/or fusion of transport vesicles to their target membrane during transport of proteins from the early endosome to the lysosome. VAMP7 localizes to late endosomes and lysosomes and is involved in the fusion of transport vesicles to their target membranes. VAMP7 is essential for heterotypic fusion of late endosomes with lysosomes and homotypic lysosomal fusion. It is also necessary for calcium regulated lysosomal exocytosis. In addition, VAMP7 is involved in the export of chylomicrons from the endoplasmic reticulum to the cis Golgi. Furthermore, VAMP7 is needed for exocytosis of mediators during eosinophil and neutrophil degranulation, and target cell killing by natural killer cells.

Regulation Of Nuclear Pre-MRNA Domain Containing 1A (RPRD1A) is upregulated in cells overexpressing cyclin-dependent kinase inhibitor p15(INK4b) and may have a part in cell cycle regulation. RPRD1A interacts with phosphorylated C-terminal heptapeptide repeat domain (CTD) of the largest RNA polymerase II subunit POLR2A, and partakes in dephosphorylation of the CTD. RPRD1A May function as a negative regulator of cyclin-D1 (CCND1) and cyclin-E (CCNE1) in the cell cycle.

Borrelia belongs to a genus of bacteria of the spirochete phylum. Borrelia causes borreliosis, which is a zoonotic, vector-borne disease transmitted mainly by ticks and some by lice, depending on the species. Of the 36 known species of Borrelia, 12 are distinguished to cause Lyme disease or borreliosis and are transmitted by ticks. The main Borrelia species causing Lyme disease are Borrelia burgdorferi, Borrelia afzelii, and Borrelia garinii. The Borrelia genus members have a linear chromosome which is about 900 kbp in length as well as an excess of both linear and circular plasmids in the 5-220 kbp size range. The plasmids are atypical, as compared to most bacterial plasmids, since they contain many paralogous sequences, a large number of pseudogenes and, in some cases, essential genes. Moreover, a number of the plasmids have features suggesting that they are prophages.