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Crystallins are the main structural proteins of the vertebrate eye lens, where they maintain the transparency and refractive index of the lens. Crystallins are divided into 3 fprotein families, α, β, & γ families. Because lens central fiber cells lose their nuclei during development, these crystallins are prepared and then retained throughout life, making them extremely stable proteins. CRYBB1 is a beta basic group member and undergoes extensive cleavage at its N-terminal extension during lens maturation.

DCTD is an allosteric enzyme that exists as a homohexamer and is part of the cytidine and deoxycytidylate deaminase protein family. DTCD uses zinc as a cofactor to catalyze the deamination of dCMP to dUMP, thus making the nucleotide substrate (dUMP) that is used by thymidylate synthase.

DHH is part of the Hedgehog family which encodes signaling molecules that are involved in regulating morphogenesis. DHH protein is a precursor that is autocatalytically cleaved, the N-terminal portion is soluble and contains the signalling activity while the C-terminal portion is involved in precursor processing. Additionally, the C-terminal product covalently attaches a cholesterol moiety to the N-terminal product, restricting the N-terminal product to the cell surface and preventing it from freely diffusing throughout the organism. Defects in DHH protein have been associated with partial gonadal dysgenesis (PGD) accompanied by minifascicular polyneuropathy. DHH plays a role both male gonadal differentiation and perineurial development.
DHH plays a role in intercellular signaling which is essential for a variety of patterning events during development. DHH functions as a spermatocyte survival factor in the testes & is essential for testes development.

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).

The recombinant Protein A/G/L is a genetically engineered protein which combines the IgG binding profiles of all Protein A, Protein G and Protein L. Protein A/G/L is a gene fusion product. Recombinant fusion protein A/G/L is comprised of 5 Ig-binding regions of protein L (B1-B2-B3-B4-B5), 5 IgG binding domains from Protein A (E-D-A-B-C) and 2 Ig-binding region of protein G (C1-C3). The recombinant Protein A/G/L is ideal for purification of monoclonal or polyclonal IgG antibodies. Protein A/G/L binds to IgG from humans, mice, rats, cows, goats, sheep, rabbits, guinea pigs, pigs, dogs and cats.

CUB Domain Containing Protein 1, also known as CDCP1 is a transmembrane protein which contains three extracellular CUB domains. CDCP1 is implicated in cell adhesion and cell matrix association. In addition, CDCP1 takes part in the regulation of anchorage versus migration or proliferation versus differentiation through its phosphorylation. CDCP1 is also a novel marker for leukemia diagnosis as well as for immature hematopoietic stem cell subsets. Furthermore, the extracellular region of human CDCP1 shares amino acid identity sequence with the mouse CDCP1.

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.

Thy-1 membrane glycoprotein (CD90) is a cell membrane protein which contains one lg-like V-type (immunoglobulin-like) domain. CD90 protein belongs to the immunoglobulin superfamily of adhesion molecules with constitutive expression on fibroblast cells. CD90 protein is involved in cell adhesion and cell communication in numerous cell types, predominantly in cells of the immune and nervous systems. CD90 may also have a role in cell-cell or cell-ligand interactions during synaptogenesis and other events in the brain. CD90 can be used as a marker for various stem cells and for the axonal processes of mature neurons. CD90 may serve as a tumor suppressor in nasopharyngeal carcinoma.

The somatomedins, or insulin-like growth factors (IGFs), comprise a family of peptides that takes part in mammalian growth and development. IGF1 mediates various growth-promoting effects of growth hormone (GH; MIM 139250). Early studies showed that growth hormone did not directly stimulate the incorporation of sulfate into cartilage, but rather acted through a serum factor, termed 'sulfation factor,' which later became known as 'somatomedin' (Daughaday et al., 1972). 3 main somatomedins have been characterized: somatomedin C (IGF1), somatomedin A (IGF2; MIM 147470), and somatomedin B (MIM 193190) (Rotwein, 1986; Rosenfeld, 2003).

BCA-1 is a CXC chemokine that is highly expressed in thesecondary lymphoid organs, such as follicles of the spleen, lymph nodes, and Peyer's patches. CXCL13 promotes the migration of B lymphocytes (compared to T cells and macrophages), by stimulating calcium influx into, and chemotaxis of, cells expressing Burkitt's lymphoma receptor 1 (BLR1). BCA1 therefore function in the homing of B lymphocytes to follicles. Human BCA-1 shares a 64% amino acid sequence similarity with the mouse protein and 23 - 34% amino acid sequence identity with other known CXC chemokines. Recombinant or chemically synthesized BCA1 is a potent chemoattractant for B lymphocytes but not T lymphocytes, monocytes or neutrophils. BLR1, a G protein-coupled receptor originally isolated from Burkitt’s lymphoma cells, has now been shown to be the specific receptor for BCA1. Among cells of the hematopoietic lineages, the expression of BLR-1, now designated CXCR-5, is restricted to B lymphocytes and a subpopulation of T helper memory cells.

CIB1 (Calcium and integrin binding 1) is regulatory protein with 50% homology to calmodulin and calcineurin B, that encodes a member of the calcium-binding protein family. CIB1 interacts with DNA-dependent protein kinase and may play a role in kinase-phosphatase regulation of DNA end joining. Also CIB1 is widely expressed and binds to a number of effectors, such as integrin αIIb, PAK1, and polo-like kinases, in different tissues.

Syntaxin 4 (STX4) is a member of the syntaxin/epimorphin family of proteins. The Syntaxin family is cellular receptors for transport vesicles which participate in exocytosis in neutrophils. Syntaxin 4 is vital for normal regulation of glucose metabolism uptake in skeletal muscle and decline in STX4 protein levels lead to reduction of whole-body hormone-stimulated glucose metabolism. STX4 is expressed in neutrophils and neutrophil-differentiated HL-60 cells. The STX4 expression in neutrophils increases with differentiation.

GMCSF is a cytokine that controls the production, differentiation, and function of granulocytes and macrophages. The active form of the protein is found extracellularly as a homodimer. This gene has been localized to a cluster of related genes at chromosome region 5q31, which is known to be associated with interstitial deletions in the 5q- syndrome and acute myelogenous leukemia. Other genes in the cluster include those encoding interleukins 4, 5, and 13.
GM-CSF stimulates the growth and differentiation of hematopoietic precursor cells from various lineages, including granulocytes, macrophages, eosinophils and erythrocytes.

Troponin I (TnI), troponin T (TnT) and troponin C (TnC) form the troponin complex of the thin filaments of striated muscle. TnI is acts as the inhibitory subunit by blocking actin-myosin interactions and thereby mediating striated muscle relaxation. The TnI subfamily contains 3 genes: TnI-skeletal-fast-twitch, TnI-skeletal-slow-twitch, and TnI-cardiac. The TNNI3 gene encodes the TnI-cardiac protein and is exclusively expressed in cardiac muscle tissues. Mutations in the TNNI3 gene cause familial hypertrophic cardiomyopathy type 7 (CMH7) and familial restrictive cardiomyopathy (RCM).

HCV is a small 50nm, enveloped, single-stranded, positive sense RNAvirus in the family Flaviviridae.
HCV has a high rate of replication with approximately one trillion particles produced each day in an infected individual. Due to lack of proofreading by the HCV RNA polymerase, the HCV has an exceptionally high mutation rate, a factor that may help it elude the host's immune response. Hepatitis C virus is classified into six genotypes(1-6) with several subtypes within each genotype. The preponderance and distribution of HCV genotypes varies globally. Genotype is clinically important in determining potential response to interferon-based therapy and the required duration of such therapy. Genotypes 1 and 4 are less responsive to interferon-based treatment than are the other genotypes (2, 3, 5 and 6).

C3b is derived from native C3 upon cleavage with the alternative pathway C3 convertase and release of C3a. C3b is essential to the function of all 3complement pathways. Initiation of each pathway generates proteolytic enzyme complexes (C3 convertases) which binds the target surface. These enzymes cleave a peptide bond in C3 releasing the anaphylatoxin C3a and activating C3b. Most of the C3b created during complement activation. Surface-bound C3b is needed in all 3 pathways for effective activation of C5 and formation of C5b-9 complexes which lyse the target cell membrane. Surface-bound C3b and its breakdown products iC3b and C3d are identifyid by various receptors on lymphoid and phagocytic cells which use the C3b ligand to stimulate antigen presentation to cells of the adaptive immune system. It results in an expansion of target-specific B-cell and T-cell populations.

Collagen triple helix repeat-containing protein 1 or CTHRC1 acts as a negative regulator of collagen matrix deposition. The protein is secreted from a 28kDa protein which is glycosylated and very conserved from lower chordates to mammals. CTHRC1 is found qualitatively in plasma of healthy human subjects. CTHRC1 plasma levels are also significantly elevated during pregnancy, in diabetes, in inflammatory and infectious conditions, in subjects with acute myeloid leukemia but not in subjects with solid cancers.CTHRC1 is highly connected with calcified tissues and cartilaginous matrix, but not with endothelial cells.

Dendritic cell and monocyte chemokinelike protein (DMC/CXCL17/VEGF-correlated chemokine 1/VCC1), is a secreted molecule with a size and predicted 3-dimensional folding pattern similar to that of chemokines CXCL8/IL8 and CXCL14/BRAK. CXCL17 is constitutively generated by airway and intestinal epithelium. CXCL17 induces the chemotaxis of quiescent, but not LPS-activated peripheral blood monocytes and dendritic cells, and it also binds these cells specifically. The expression of CXCL17 is increased in endothelial cells when they are induced to form tubes in vitro. CXCL17, CXCL1/GRO and CXCL8/IL8 which have roles in angiogenesis, show significantly correlated expression with that of VEGF in primary lung, breast and esophageal tumors. Therefore, CXCL17 is suggested to have a role in tumor angiogenesis. The mature Rat CXCL17 shares 82%, 71% amino acid sequence identity with mouse, human CXCL17, respectively.

Stem cell factor / KIT ligand (SCF) is a cytokine which binds CD117(c-Kit). SCF is also known as "steel factor" or "c-kit ligand". SCF exists in two forms, cell surface bound SCF and soluble (or free) SCF. Soluble SCF is produced by the cleavage of surface bound SCF by metalloproteases. SCF is a growth factor important for the survival, proliferation, and differentiation of hematopoietic stem cells and other hematopoietic progenitor cells. One of its roles is to change the BFU-E (burst-forming unit-erythroid) cells, which are the earliest erythrocyte precursors in the erythrocytic series, into the CFU-E (colony-forming unit-erythroid).

SCG5 also called 7B2 protein is localized in neuroendocrine tissues. SCG5 functions as a chaperone protein for the proprotein convertase PC2 and is essential for the production of an active PC2 enzyme.

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.