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SDF-1 (stromal cell-derived factor-1) is small cytokine belonging to the chemokine family that is officially designated Chemokine (C-X-C motif) ligand 12 (CXCL12). It is produced in two forms, SDF-1?/CXCL12a and SDF-1?/CXCL12b, by alternate splicing of the same gene. Chemokines are characterized by the presence of four conserved cysteines, which form two disulfide bonds. The CXCL12 proteins belong to the group of CXC chemokines, whose initial pair of cysteines are separated by one intervening amino acid. CXCL12 is strongly chemotactic for lymphocytes and has been implicated as an important cell co-ordinator during development. During embryogenesis it directs the migration of hematopoietic cells from foetal liver to bone marrow. Mice which were knocked-out for CXCL12 gene were lethal before the birth or within just 1 hour of life. As another role, CXCL12a alters also the electrophysiology of neurons. CXCL12 was shown to be expressend in many tissues in mice (including brain, thymus, heart, lung, liver, kidney, spleen and bone marrow).
The receptor for this chemokine is CXCR4, which was previously called fusin. This CXCL12-CXCR4 interaction used to be considered exclusive (unlike for other chemokines and their receptors), but recently it was suggested that CXCL12 is also bound by CXCR7 receptor.
The gene for CXCL12 is located on human chromosome 10. In human and mouse both CXCL12 and CXCR4 show high identity of sequence: 99% and 90%, respectively.

Complement Component C5a (C5a) is involved in the complement system and it is encoded by the C5 gene in human. Complement C5 is cleaved into C5a and C5b. C5a has an imperative role in chemotaxis and C5b forms the 1st part of the complement membrane attack complex. Complement C5 is the 5th component of complement, which plays a central role in inflammatory and cell killing processes. C5a protein is composed of alpha and beta polypeptide chains, which are linked by a disulfide bridge. An activation peptide, C5a, which is an anaphylatoxin, which has potent spasmogenic and chemotactic activity, is derivative from the alpha polypeptide via cleavage with a convertase. The C5b macromolecular cleavage product forms a complex with the C6 complement component, and this complex is the basis for creation of the membrane attack complex, which includes supplementary complement components.

Akt1, also known as "Akt" or protein kinaseB (PKB) is an important molecule in mammaliancellular signaling.
In humans, there are three genes in the "Akt family": Akt1, Akt2, and Akt3. These enzymesare members of the serine/threonine-specific protein kinasefamily (EC2.7.11.1).
Akt1 is involved in cellular survival pathways, by inhibiting apoptoticprocesses. Akt1 is also able to induce protein synthesispathways, and is therefore a key signaling protein in the cellular pathways that lead to skeletal muscle hypertrophy, and general tissue growth. Since it can block apoptosis, and thereby promote cell survival, Akt1 has been implicated as a major factor in many types of cancer. Akt (now also called Akt1) was originally identified as the oncogenein the transforming retrovirus, AKT8.

Pleiotrophin (Osteoblast-Specific Factor-1, OSF-1) contains 136 amino acid residues. The sequence is very rich in cationic amino acids (24% of the residues); lysine cluster sequences are found in the N-terminal and C-terminal ends of the structure.
The OSF-1 gene was shown by Northern blotting analysis to be expressed in mouse calvarial osteoblast-enriched cells and in mouse brain tissues, but not in thymus, spleen, kidney, liver, lung, testis or heart. Pleiotrophin has the ability to promote adhesion, migration, expansion, and differentiation of human osteoprogenitor cells. In addition to certain types of cancer, the embryonic growth and differentiation factor pleiotrophin is found also in adults in inflammatory diseases. In osteoarthritis, pleiotrophin is especially expressed in early stages, and its concentrations in the synovial fluid could serve as a marker for the progress of the disease. Pleitrophin might be involved in cartilage repair in osteoarthritis, in particular, in earlier stages.

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.

Single-Stranded DNA Binding Protein 1 (SSBP) participates in mitochondrial biogenesis. SSBP binds preferentially and cooperatively to ss-DNA. The SSBP protein is involved in mitochondrial DNA replication and associates with mitochondrial DNA.

ROBLD3 is a member of the GAMAD family. ROBLD3 is an adapter protein which enhances the efficiency of the MAP kinase cascade and facilitates the activation of MAPK2. ROBLD3 compels the recruitment of MP1 to late endosomes where they form a very stable heterodimeric complex required for ERK activation on endosomes. In humans, a mutation in the ROBLD3 gene has been associated with a primary immunodeficiency syndrome, and suggests a role for the ROBLD3 protein in endosomal biogenesis.

Vascular endothelial growth factor is an important signaling protein involved in both vasculogenesis and angiogenesis. As its name implies, VEGF activity has been mostly studied on cells of the vascular endothelium, although it does have effects on a number of other cell types (e.g. stimulation monocyte/macrophage migration, neurons, cancer cells, kidney epithelial cells ).VEGF mediates increased vascular permeability, induces angiogenesis, vasculogenesis and endothelial cell growth, promotes cell migration, and inhibits apoptosis. In vitro, VEGF has been shown to stimulate endothelial cell mitogenesis and cell migration. VEGF is also a vasodilator and increases microvascular permeability and was originally referred to as vascular permeability factor.
Elevated levels of this protein is linked to POEMS syndrome, also known as Crow-Fukase syndrome. Mutations in this gene have been associated with proliferative and nonproliferative diabetic retinopathy.

RAB11A is part of the small GTPase superfamily, Rab family. RAB11A is related with both constitutive and regulated secretory pathways, and takes part in protein transport. RAB11A is a well-known marker for protein trafficking, sorting, and recycling in the endosomal pathway. RAB11A is a main regulator of membrane delivery during cytokinesis.

TNFR1 belongs to the TNF-receptor superfamily. TNFR1 is a receptor for TNFSF2/TNF-alpha and homotrimeric TNFSF1/lymphotoxin-alpha.
There are 2 types of soluble TNF receptors: sTNFR-I and sTNFR-II, which act to neutralize the biological activities of TNF alpha and TNF beta. The levels of these soluble receptors seem to increase as a result of shedding of the extracellular domains of the membrane bound receptors. TNF-a, TNFR1 and TNFR2 have roles in cellular differentiation. TNFR1 and TNFR2 function in cell type-specific renal injury.
TNFR1 is capable of signaling both cell survival and apoptosis. TNFR1-induced apoptosis requires 2 sequential signaling complexes. TNFR1 is capable of activating NF-kappaB, mediate apoptosis, and function as a regulator of inflammation. Oxidative stress promotes TNFR1 and TNFR2 self-interaction, ligand-independent and enhanced ligand-dependent TNF signaling. TNFR1 contributes to the induction of non-cytocidal TNF effects including anti-viral state and activation of the acid sphingomyelinase. Human TNFR1 has a major region which controls cell surface expression. High levels of soluble TNF receptors are found in the amniotic fluid of pregnant women.
Germline mutations of the extracellular domains of TNFR1 are linked to the autosomal dominant periodic fever syndrome. The impaired receptor clearance is believed to be a mechanism of the disease. Familial hibernian fever (FHF) is caused by defects in TNFRSF1A gene.

UBL3 - a member of the ubiquitin-like family is found in the membrane. UBL3 holds two N-glycosylation sites, a C-terminal prenylation site and a protein kinase C phosphorylation site. Even though Ubiquitin-like proteins are not directly involved in protein degradation, it seems they have several mechanistic similarities to the ubiquitin pathway.

Mature T-Cell Proliferation 1, also known as MTCP1 was recognized by involvement in some t(X;14) translocations linked with mature T-cellproliferations. This region has a complex gene structure, with a common promoter and 5' exon spliced to two dissimilar sets of 3' exons which encode two different proteins. It represents the upstream 13 kDa protein which belongs to the TCL1 family. In addition, MTCP1 enhances the phosphorylation and activation of AKT1 and AKT2. MTCP1 is involved in leukemogenesis.Among the diseases associated with MTCP1 are queensland tick typhus, and african tick-bite fever.

GPN-loop GTPase 1 (GPN1) is a member of the GPN-loop GTPase family. GPN1 is a guanosine triphosphatase enzyme which has a role in DNA repair and may function in activation of transcription. Small GTPases, which share a biochemical mechanism, act as binary molecular switches and function in the cell is nucleocytoplasmic transport of both proteins and RNA. In addition, GPN1 establishs an interface between the RNA polymerase II enzyme and chaperone/scaffolding protein, proposing that it is essential to connect RNA polymerase II to regulators of protein complex formation. GPN1 may also be involved in nuclear localization of XPA.

MAP kinase-activated protein kinase 3 (MAPKAPK3) is involved in inflammatory Reaction by regulating tumor necrosis factor (TNF) and IL6 production post-transcriptionally. MAPKAPK3 phosphorylates AU-rich elements (AREs)-binding proteins, like TTP/ZFP36, leading to control of stability and translation of TNF and IL6 mRNAs. Phosphorylation of TTP/ZFP36 (a major post-transcriptional regulator of TNF), promotes its binding to 14-3-3 proteins and reduces its ARE mRNA affinity resulting in inhibition of dependent degradation of ARE-containing transcript. MAPKAPK3 is activated by growth inducers and stress stimulation of cells.

Nucleic acid binding protein 1 is a part of the SOSS complex, amultiprotein complex which functions downstream of the MRN complex to promote DNA repair and G2/M checkpoint.In the SOSS complex, NABP1 acts as a sensor of single-stranded DNA which binds to single-stranded DNA, inparticular to polypyrimidines. The SOSS complex links with DNA lesions and affects diverse endpoints in the cellular DNA damage response including cell-cycle checkpoint activation, recombinational repair andmaintenance of genomic stability. NABP1 is essential for efficient homologous recombination-dependent repairof double-strand breaks (DSBs) and ATM-dependent signaling pathways.

Vesicular overexpressed in cancer prosurvival protein 1 (VOPP1) has been previously shown to be over-expressed in human glioblastoma multiform and squamous cell carcinoma. VOPP1 is a crucial regulator of NF-kappaB signaling, and this high-level, amplification-mediated VOPP1 expression, such as that occurring in tumors with amplified EGFR, might impact the resistance to apoptosis.

Rho-related GTP-binding protein RhoB (RhoB) belongs to the Rho GTP-binding protein family. RhoB facilitates apoptosis in neoplastically transformed cells after DNA damage. RhoB has a negative role in tumorigenesis since deletion causes tumor formation.

Gametocyte Specific Factor 1 (GTSF1) is a member of the UPF0224 (FAM112) family and contains 1 CHHC-type zinc finger. A key paralog of the GTSF1 gene is GTSF1L.

Vacuolar protein sorting-associated protein 4B (VPS4B) is a member of the AAA (ATPases associated with diverse cellular activities) family. VPS4B is involved in late steps of the endosomal multivesicular bodies (MVB) pathway and recognizes membrane-associated ESCRT-III assemblies and catalyzes their disassembly, probably in combination with membrane fission. A dominant negative mutant of VPS4B inhibits vacuolar protein sorting and also arrest HIV-1 and MLV budding.

Family with Sequence Similarity 3, Member A (FAM3A) is a member of the FAM3 family along with FAM3B (Pander) protein which induces apoptosis of pancreatic alpha and beta cells. FAM3A is a cytokine-like protein, which is expressed in almost all tissues such as the testis, pancreas, adrenal, placenta, brain, fetal brain, liver, kidney, skeletal muscle and the heart. FAM3A gene expression may be regulated by peroxisome proliferator-activated receptor gamma, and the FAM3A protein might be involved in the regulation of glucose and lipid metabolism. Although the function of the FAM3A protein has been unclear until now, it may act as a defensin against invading fungal microorganisms.

Transcription Factor B2, Mitochondrial (TFB2M) is an S-adenosyl-L-methionine-dependent methyltransferase which specifically dimethylates mitochondrial 12S rRNA at the conserved stem loop. In addition, TFB2M is essential for basal transcription of mitochondrial DNA, most likely via its interaction with POLRMT and TFAM. TFB2M promotes transcription independently of the methyltransferase activity. TFB2M like TFB1M, activates transcription of mitochondrial DNA more effectively, whilst having less methyltransferase activity.

PRND is a membrane glycosylphosphatidylinositol-anchored glycoprotein which exists mainly in testis. PRND is expressed during embryogenesis, although in the central nervous system it is expressed minimally .Mutations in PRND may cause neurological disorders. PRND located on chromosome 20, about 20 kbp downstream of the gene encoding cellular prion protein, to which it is biochemically and structurally analogous.

Ribosomal Protein 4X (RPS4X) is ribosomal protein S4, a component of the 40S subunit which is a part from the S4E family of ribosomal proteins. Ribosomal protein S4 is the only ribosomal protein known to be encoded by more than one gene, that is RPS4X and ribosomal protein S4, Y-linked (RPS4Y). Both isoforms encoded by these genes are not the same, but are functionally alike.