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CALR is a multifunctional protein that acts as a main Ca(2+)-binding (storage) protein in the lumen of the endoplasmic reticulum. Calreticulin is localized in the nucleus, and participates in transcription regulation. Calreticulin binds to the synthetic peptide KLGFFKR, which is nearly identical to an amino acid sequence in the DNA-binding domain of the superfamily of nuclear receptors. CALR binds to antibodies in specific sera of systemic lupus and Sjogren patients which have anti-Ro/SSA antibodies, it is well conserved among species, and it is positioned in the endoplasmic and sarcoplasmic reticulum where it binds calcium. The amino terminus of CALR interacts with the DNA-binding domain of the glucocorticoid receptor and prevents the receptor from binding to its specific glucocorticoid response element. CALR reduces the binding of androgen receptor to its hormone-responsive DNA element and inhibits androgen receptor and retinoic acid receptor transcriptional activities in vivo, as well as retinoic acid-induced neuronal differentiation. Therefore, CALR acts as a significant modulator of the regulation of gene transcription by nuclear hormone receptors.

Protein A is a cell wall component produced by several strains of Staphylococcus aureus. The recombinant Protein A is genetically engineered protein and holds 5 IgG-binding regions of protein A. Recombinant Protein A functions basically the same as native Protein A and is perfect for purification of polyclonal or monoclonal IgG antibodies. Protein A binds to human IgG1, IgG2 and IgG4, mouse IgG2a, IgG2b and IgG3 and rat IgG2c. Protein A also binds to total IgG from rabbit, pig, dog, cat, and guinea pig.

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.

Voltage-gated sodium channels are transmembrane glycoprotein complexes composed of a large alpha subunit and one or more regulatory beta subunits. SCN3B is a part of the sodium channel beta subunit gene family whose members are responsible for the generation and propagation of action potentials in neurons and muscle. SCN3B influences the inactivation kinetics of the sodium channel.

Sclerostin (SOST) is a secreted glycoprotein with a C-terminal cysteine knot-like (CTCK) domain and sequence similarity to the DAN (differential screening-selected gene aberrative in neuroblastoma) family of bone morphogenetic protein antagonists. Sclerostin functions as a negative regulator of bone growth, by inhibiting bone formation. SOST is expressed mainly in the bone, cartilage, kidney, liver, bone marrow and primary osteoblasts differentiated for 21 days. SOST gene defects cause sclerosteosis and bone dysplasia.

Neurotensin (NTS) is a common precursor for 2 peptides, neuromedin N and neurotensin. Neurotensin is a secreted tridecapeptide, which is generally distributed throughout the central nervous system, and may serve as a neurotransmitter or a neuromodulator. NTS is involved in dopamine-associated pathophysiological events, in the maintenance of gut structure and function, and in the regulation of fat metabolism. Tissue-specific processing may initiate the formation in some tissues of larger forms of neuromedin N and neurotensin. The large forms may embody more stable peptides which are also biologically active.

Chemokine (C-C motif) ligand 2 (CCL2) is a small cytokine belongs to the CC chemokine family which is also known as monocyte chemotactic protein-1 (MCP-1). MCP 1 is found at the site of tooth eruption and bone degradation. In the bone, CCL2 is expressed by mature osteoclasts. CCL2 recruits immune cells, such as monocytes, to sites of tissue injury and infection. MCP 1is produced as a protein precursor containing signal peptide of 23 amino acids and a mature peptide of 76 amino acids. As with many other CC chemokines, CCL2 is located on chromosome 17 in humans. The cell surface receptors that bind CCL2 are CCR2 and CCR5.

Osteoprotegerin, which is a member of the tumor necrosis factor receptor superfamily and is involved in the regulation of bone metabolism. OPGand its ligand (OPGL) are cytokines regulating osteoclasto-genesis. OPGL binds to receptors on the surface of preosteoclasts and stimulates their differentiation into active osteoclasts. This leads to osteoresorption. OPG inhibits this osteoclasto-genesis (OPG is secreted by osteoblasts, and binds to OPGL, thus inhibiting maturation of osteoclasts and osteoresorption). The degree and activity of osteoresorption depend mainly on the balance between OPG and its ligand (OPGL); factors increasing OPGL expression mostly reduce OPG expression and vice versa.

ACTN1 encodes a nonmuscle, cytoskeletal, alpha actinin isoform and maps to the same site as the structurally similar erythroid beta spectrin gene. Alpha actinins belong to the spectrin gene superfamily which represents a diverse group of cytoskeletal proteins, including the alpha and beta spectrins and dystrophins. Alpha actinin is an actin-binding protein with multiple roles in different cell types. In nonmuscle cells, the cytoskeletal isoform is found along microfilament bundles and adherens-type junctions, where it is involved in binding actin to the membrane. In contrast, skeletal, cardiac, and smooth muscle isoforms are localized to the Z-disc and analogous dense bodies, where they help anchor the myofibrillar actin filaments.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

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.

GDF8 is a member of the bone morphogenetic protein (BMP) family and the TGF-beta superfamily. This group of proteins is characterized by a polybasic proteolytic processing site which is cleaved to produce a mature protein containing seven conserved cysteine residues. The members of this family are regulators of cell growth and differentiation in both embryonic and adult tissues. This gene is thought to encode a secreted protein which negatively regulates skeletal muscle growth.

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.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

TUBG1 belongs to the tubulin superfamily. TUBG1 localizes to the centrosome and binds to microtubules to create the gamma-tubulin ring complex. TUBG1 facilitates the microtubule nucleation and is essential for microtubule formation and progression of the cell cycle.

Lactoferrin is a glycoprotein that belongs to the transferrin family of iron binding proteins. It is found in human breast milk as well as most epithelial surface secretions including tears, nasogastric, saliva, and bronchial. Lactoferrin binds 2 molecules of iron with very high affinity. Lactoferrin inhibits bacterial growth by withholding iron, its N-terminal region is an antimicrobial peptide. Lactotransferrin acts synergistically with lysozyme to potentiate the activity of both proteins. The multifunctional protein lactoferrin has many physiological possible roles. It is often referred to as an innate defense protein and frequently serves as the first line of defense in protection against pathogens. It has been shown to have the ability to bind iron, it is a natural anti-bacterial, anti-fungal and anti-viral, it is an antioxidant and it also has immunomodulatory properties. It has many beneficial properties, which make it a good candidate for a number of product applications. Considerable research is currently going on to explain the various suggested biological functions of lactoferrin.

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.

There are several proteolytic fragments or specific domains of proteins that act as inhibitors of angiogenesis. These include fragments of plasminogen such as Angiostatin protein kringles 1-4 and kringles 1-5, Endostatin, Restin, PEX, the N-terminal fragment of prolactin, and the Nterminally truncated platelet factor. Angiostatin is a proteolytic protein fragment of plasminogen that is comprised of the first 4 kringle regions. Angiostatin k1-4 prevents the growth of endothelial cells, and its systemic administration inhibits the growth of primary carcinomas in mice. Angiostatin Kringles 1-3 segment has a larger inhibitory activity than the Angiostatin kringles 1-4 fragment. The protease-activated angiostatin kringles 1-5 is the most potent plasminogen fragment with over 50 times larger endothelial cell specific inhibitory activity. Angiostatin kringles 1-5 systemic administration inhibits growth of fibrosarcoma and significantly reduces neovascularization.
Angiostatin is an angiogenesis inhibitor in mouse serum and urine. Angiostatin is a 38 kDa protein fragment of the plasminogen composed of the 1st 4 kringle domains of plasminogen. Angiostatin K1-4 is also named plasminogen kringles 1-4 and PK1-4.
Angiostatin protein is manufactured by the protelytic cleavage of plasminogen by a serine protease from several prostate carcinoma cell lines. The manufacturing of angiostatin by pancreatic cancer cells can be inhibited by TGF-beta 1 along with plasminogen activator inhibitor type-1 (PAI1).

SDCBP is a multifunctional intracellular adapter protein. SDCBP protein has tandemly repeated PDZ domains which react with the FYA (phe-tyr-ala) carboxyterminal amino acid sequence of the syndecans. SDCBP is has a role in organization of protein complexes in the plasma membranes, regulation of B-cell development, activation of transcription factors, intracellular trafficking and cell-surface targeting, synaptic transmission, and axonal outgrowth.

DCTN2 is a 50kDa subunit of dynactin, which is a macromolecular complex consisting of 10-11 subunits ranging in size from 22 to 150 kDa. Dynactin binds to both microtubules and cytoplasmic dynein. Dynactin is involved in a various cellular functions, including ER-to-Golgi transport, the centripetal movement of lysosomes and endosomes, spindle formation, chromosome movement, nuclear positioning, and axonogenesis. The DCTN2 subunit is present in 4-5 copies per dynactin molecule. DCTN2 is comprised of 3 short alpha-helical coiled-coil domains which mediate association with self or other dynactin subunits. DCTN2 interacts directly with the largest subunit (p150) of dynactin and is able to affix p150 in place. DCTN2 modulates cytoplasmic dynein binding to an organelle, and plays a part in prometaphase chromosome alignment and spindle organization during mitosis. DCTN2 is involved in anchoring microtubules to centrosomes. DCTN2 has a role in synapse formation during brain development.

Calcium-binding protein 39-like (CAB39L), is analogous to MO25 and located in the serum of virtually half of all patients diagnosed with acute monocytic leukemia. CAB39L plays a role in carcinogenesis. Furthermore, LKB1 activity raises upon the binding of a regulatory complex consisting of the STE20-related adaptor-alpha (STRAD alpha) pseudo kinase and the CAB39L.