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C8, a component of the complement system consists of three polypeptides C8A, C8B and C8G and takes part in the formation of Membrane Attack Complex (MAC). Patients with C8 deficiency are exposed to several bacteria infections. C8G, a member of the lipocalin family and calycin superfamily, is a secreted protein that can bind retinol. C8G is created in the liver, monocytes and fibroblast and has a role in clearing pathogens from an infected host.

TCL1A (T-cell leukemia/lymphoma 1A) is a protein with a possible role in intracellular regulation of T cell signaling. TCL1A enhances cell proliferation, stabilizes mitochondrial membrane potential and promotes cell survival. TCL1A is restricted in the T-cell lineage to immature thymocytes and activated peripheral lymphocytes. TCL1A is preferentially expressed early in T and B-lymphocyte differentiation. Chromosomal anomalies activating TCL1A are found in chronic T-cell leukemias (T-CLL).
TCL1A enhances the phosphorylation and activation of AKT1, AKT2 and AKT3. TCL1A promotes nuclear translocation of AKT1. TCL1A binds to the pleckstrin homology domain of Akt (protein kinase B) family proteins, which facilitates Akt dimerization and activity. By increasing Akt activity, TCL1A can enhance the serine/threonine phosphorylation of major Akt signaling substrates, for example Ikk complex, mTOR, BAD, p70S6 kinase, FOXO transcription factors and GSK3b. These substrates regulate cellular differentiation, growth, survival, and metabolism.

T-cell leukemia/lymphoma 1B, also known as TCL1B is a member of the TCL1 family. TCL1B is expressed in a variety of tissues as well as the placenta and testis. Moreover, TCL1B enhances the phosphorylation and activation of AKT1 and AKT2.

GCSAM is a protein which functions in signal transduction pathways and whose expression raises in germinal cell lymphomas. GCSAM contains a putative PDZ-interacting domain, an immunoreceptor tyrosine-based activation motif (ITAM), and two putative SH2 binding sites. In B cells, GCSAM expression is particularly induced by interleukin-4.

E-cadherin (uvomorulin, cell-CAM120/80) is a calcium dependent cell adhesion molecule expressed predominately in epithelial tissues. It plays an important role in the growth and development of cells via the mechanisms of control of tissue architecture and the maintenance of tissue integrity. Numerous studies have demonstrated that reduction and/or loss of Ecadherin expression in carcinomas correlates positively with the potential of these tumors for invasion and metastasis.

Complement Factor B, also known as CFB, encodes complement factor B which is a component of the alternative pathway of complement activation. Factor B circulates in the blood as a single chain polypeptide. Once the alternative pathway is activated it is cleaved by complement factor D yielding the noncatalytic chain Ba and the catalytic subunit Bb. The active subunit Bb is a serine protease which connects with C3b to form the alternative pathway C3 convertase. Also, Bb is involved in the proliferation of preactivated B lymphocytes, while Ba inhibits their proliferation.

Geminin is a 25 kDa nuclear protein, which inhibits DNA replication and is degraded during the mitotic phase of the cell cycle. Geminin controls replication by binding to the licensing factor Cdt1, and is involved in neural differentiation. In addition, Geminin directly interacts with Six3 and Hox homeodomain proteins during embryogenesis and inhibits their functions. Geminin can also promote DNA replication. Geminin has 2 roles in 2 different stages of the cell cycle: Geminin is a negative regulator of DNA replication during the “S phase” of the cell cycle. Inhibition of Geminin during the “S phase” (by RNAi) results in an additional round of replication of portions of the genome. During the “M phase” of the cell cycle (mitosis) Geminin stabilizes the replication factor Cdt1 promoting DNA replication during the next cell cycle. Moreover, inhibition of Geminin during mitosis (by RNAi) causes destabilization of Cdt1 protein and impairment of DNA replication during the next cell cycle. Geminin thus guarantees that only one round of replication occurs during each cell cycle. It was discovered that Geminin is overexpressed in a number of malignancies and cancer cell lines. This maintains the concept that Geminin has also a positive role in DNA replication and cell cycle progression. Geminin accumulates through S, G2 and M phases of the cell cycle but is absent during the G1 phase. During the metaphase/anaphase transition of mitosis Geminin levels decrease.

CHMP2B is a member of the vacuolar sorting protein family. CHMP2B is a component of the ESCRT-III complex which is essential for sorting endosomal articles into multivesicular bodies (MVBs), and are also obligatory for the formation of these bodies. CHMP2B is usually found in brain, heart, skeletal muscle, small intestine, pancreas, lung, placenta and leukocytes.

Glycoprotein Nmb (GPNMB) is a member of the PMEL/NMB family. GPNMB is a type I transmembrane glycoprotein which exhibits homology to the pMEL17 precursor, a melanocyte-specific protein. GPNMB is expressed in the lowly metastatic human melanoma cell lines and xenografts but has no expression in the highly metastatic cell lines. GPNMB might be involved in growth delay and reduction of metastatic potential. GPNMB is up-regulated in a number of cancer cells, including in glioblastoma multiforme. GPNMB is expressed in many melanoma cells, as well as in tissue macrophages, including liver Kuppfer cells and lung alveolar macrophages, in podocytes and in some cells of the ciliary body of the eye (at protein level). GPNMB is hardly detectable in the healthy brain.

Lumican also known as LUM belongs to the small leucine-rich proteoglycan (SLRP) family which comprises decorin, biglycan, fibromodulin, keratocan, epiphycan, and osteoglycin. Furthermore we can see that in these bifunctional molecules, the protein moiety binds collagen fibrils and the highly charged hydrophilic glycosaminoglycans regulate interfibrillar spacings. Lumican is the main keratan sulfate proteoglycan of the cornea however LUM is also distributed in interstitial collagenous matrices throughout the body. Lumican regulates collagen fibril organization and circumferential growth, corneal transparency, epithelial cell migration and tissue repair. Among the diseases associated with LUM is posterior amorphous corneal dystrophy.

Purine-Rich Element Binding Protein B (PURB) is a single-stranded DNA-binding protein which takes part in the dendritic transport of a subset of mRNAs. PURB operates as repressor in myoblasts and fibroblasts in the control of vascular smooth muscle alpha-actin gene transcription. PURB binds preferentially to the single strand of the purine-rich element termed PUR, which is present at origins of replication and in gene flanking regions in various eukaryotes from yeasts through humans.

Parvalbumin alpha (PVALB) is a member of a larger group of EF hand proteins. PVALB is a high affinity calcium ion-binding protein which is structurally and functionally similar to calmodulin and troponin C. Parvalbumin is expressed in a specific population of GABAergic interneurones which are believed to have a role in maintaining the balance between excitation and inhibition in the cortex as well as the hippocampus.

H3F3A is a member of the histone H3 family. Histones are basic nuclear proteins which are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. Histones play a significant role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated by a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling. Two molecules of each of the four core histones H2A, H2B, H3, and H4 form an octamer, around that approximately 146 bp of DNA is wrapped in repeating units, called nucleosomes. The linker histone, H1, interacts with linker DNA between nucleosomes and functions in the compaction of chromatin into higher order structures.

CPLX1 is part of the SNARE family complex binding proteins that are catalysts or inhibitors of vesicle exocytosis. CPLX1 shows reduced Ca2+-triggered fast neurotransmitter release at hippocampal glutamatergic synapses, indicating that CPLX1 is a positive regulator of transmitter release. In contrast, CPLX1 inhibits SNARE-mediated liposome and cell fusions in vitro, that result in hypothesis thus acts as a fusion clamp of synaptic exocytosis. CPLX1 regulates a late step in synaptic vesicle exocytosis.

Coproporphyrinogen Oxidase (CPOX) which is localized to the internal membrane space of erythrocytes takes part in the 6th phase of heme biosynthesis. CPOX catalyzes the oxidative decarboxylation of propionic acid side chains of rings A and B of coproporphyrinogen III. Mutations in human CPOX gene forecast the clinical result of the disease, with either hepatic hereditary coproporphyria or hematological manifestations of erythropoietic harderoporphyria.

Coagulation factor VIII participates in the intrinsic pathway of blood coagulation; factor VIII is a cofactor for factor IXa which, in the presence of Ca+2 and phospholipids, converts factor X to the activated form Xa. This gene produces two alternatively spliced transcripts. Transcript variant 1 encodes a large glycoprotein, isoform a, which circulates in plasma and associates with von Willebrand factor in a noncovalent complex. This protein undergoes multiple cleavage events. Transcript variant 2 encodes a putative small protein, isoform b, which consists primarily of the phospholipid binding domain of factor VIIIc. This binding domain is essential for coagulant activity. Defects in this gene results in hemophilia A, a common recessive X-linked coagulation disorder.

Speckle-type POZ protein (SPOP) belongs to the Tdpoz family containing one N-terminal MATH (Meprin and TRAF homology) domain and one C-terminal BTB/POZ domain. SPOP inhibits IPF1/PDX1 transactivation of established target promoters, may be by recruiting a repressor complex. SPOP is involved in ubiquitinylation and protein degradation as a result of an interaction with CUL-3.

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 modules: Module 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.

EBI3 has an induced expression in B lymphocytes in reaction to Epstein-Barr virus infection. EBI3 encodes a secreted glycoprotein belonging to the hematopoietin receptor family, and heterodimerizes with a 28 kDa protein to form iIL-27. EBI3 drives rapid clonal expansion of naive cd4(+) t-cells. EBI3 strongly synergizes with IL-12 to activate IFN-gamma production of naive cd4(+) t-cells. EBI3 mediates its biologic effects through the cytokine receptor wsx-1/tccr.

Hepatitis A Virus Cellular Receptor 2 (HAVCR2) is a member of the immunoglobulin superfamily. HACVR2 controls macrophage activation. HACVR2 inhibits T-helper type 1 lymphocyte (Th1)-mediated auto- and alloimmune responses and stimulates immunological tolerance.

Epiregulin is part of the EGF family. Epiregulin functions as a ligand of EGFR, as well as a ligand of most members of the ERBB (v-erb-b2 oncogene homolog) family of tyrosine-kinase receptors.Epiregulin is expressed mostly in the placenta and peripheral blood leukocytes and in specific carcinomas of the bladder, lung, kidney and colon. Epiregulin stimulates the proliferation of keratinocytes, hepatocytes, fibroblasts and vascular smooth muscle cells. Epiregulin inhibits the growth of several tumor-derived epithelial cell lines. Human Epiregulin is initially synthesized as a glycosylated 19.0 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a 6.0 kDa mature secreted sequence.

Native human C3 is a naturally glycosylated polypeptide containing two disulfide-linked chains. C3 is central to the activation of all 3 pathways of complement activation. Initiation of each pathway generates proteolytic enzyme complexes which binds the target surface. These enzymes cleave a peptide bond in C3 releasing the anaphylatoxin C3a and activating C3b. Most of the C3 activated during complement activation never attaches to the surface due to its thioester reaction with water forming fluid phase C3b which is rapidly inactivated by factors H and I forming iC3b. Surface-bound C3b is necessary in all 3 pathways for efficient activation of C5 and formation of C5b-9 complexes that lyse the target cell membrane.

Complement C4c is a degradation product of C4b which is cleaved by C4b/C3b inactivator to yield C4d and C4c.
Complement C4c interacts with C1 and C2 to form C3 convertase of the classic activation pathway. Systemic lupus erythematosus (SLE) is often associated with congenital C4 deficiency. Reduced levels of components of the classic pathway (C1, C2, C4, C3) are common after such activation, e.g. in SLE, acute serum sickness and conditions associated with circulating immune complexes.

ANGPTL3 and ANGPTL4 are angiopoietin-like proteins secreted and expressed mainly by the liver, their role being the regulation of triglyceride metabolism by inhibiting the lipolysis of triglyceride-rich lipoproteins. During different nutritional states (feeding/fasting) the levels of the circulating triglycerides are regulated by Angptl3 and Angptl4 through differential inhibition of Lipoprotein lipase (LPL) as shown by the experimental data. The molecular structure of ANGPTL3 is similar to that of the angiopoietins (vascular endothelial growth factors). Deletion mutants of human Angiopoietin 5 were used in order to demonstrate that the N-terminal domain (fragment 17-207) and not the C-terminal fibrinogen-like domain (fragment 207-460) increased the plasma triglyceride levels in mice.