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Myeloid leukemia factor 1 (MLF1) is a member of the MLF family, and is a widely expressed negative regulator of cell cycle progression functioning upstream of the tumor suppressor p53. MLF1 hinders the erythropoietin-induced erythroid terminal differentiation by averting cells from exiting the cell cycle through suppression of CDKN1B/p27Kip1 levels. MLF1 generally functions in multi-potent progenitor cells, and its dysregulation may be to some extent responsible for leukemogenesis. Translocations between the MLF1 gene and nucleophosmin are linked to myelodysplastic syndrome and acute myeloid leukemia.

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.

DDX39A which is a part of the DEAD box protein family is characterized by the conserved motif Asp-Glu-Ala-Asp. This pattern is implicated in a various cellular processes involving alteration of RNA secondary structure, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Several members of the DEAD box protein family are taking part in embryogenesis, spermatogenesis, and cellular growth and division.

Myosin is a hexameric ATPase cellular motor protein, which is composed of 2 heavy chains, 2 non-phosphorylatable alkali light chains, and 2 phosphorylatable regulatory light chains.
MYL1 gene encodes a myosin alkali light chain expressed in fast skeletal muscle. Two transcript variants have been identified for the MYL1 gene. In humans MYL1 is localized to chromosome 2q32.1-qter. The Myl1 locus encodes two alkali myosin light chains- Mlc1f and Mlc3f, from two promoters that are differentially regulated throughout development. The Mlc1f promoter is active in embryonic, fetal and adult fast skeletal muscle while the Mlc3f promoter is upregulated during fetal development and stays on in adult fast skeletal muscle.

Endocrine gland-derived vascular endothelial growth factor (EG-VEGF) induces proliferation, migration, and fenestration in capillary endothelial cells derived from endocrine glands. Its expression is induced by hypoxia and is restricted to the steroidogenic glands (ovary, testis, adrenal, and placenta). Its expression is often complementary to the expression of VEGF (MIM 192240), suggesting that these molecules function in a coordinated manner. EG-VEGF potently contracts gastrointestinal (gi) smooth muscle. Induces proliferation, migration and fenestration (the formation of membrane discontinuities) in capillary endothelial cells derived from endocrine glands. Has little or no effect on a variety of other endothelial and non-endothelial cell types.

NSL1 holds two coiled-coil domains.NSL1 proteins, localized to kinetochores - chromosome associated structures which attach to microtubules and mediate chromosome movements throughout cell division. NSL1 is a fragment of a conserved protein complex that hold two chromodomain-containing proteins and a component of the outer plate of the kinetochore. NSL1 connect centromeric heterochromatin with the outer kinetochore structure. Several transcript variants are known to encod different isoforms for this gene.

BIN1 is a nucleocytoplasmic adaptor protein, one of which was primarily identified as MYC-interacting protein having the characteristics of a tumor suppressor. BIN1 protein interacts with and inhibits the oncogenic activity of the myc oncoprotein that is a key player in many human cancers. The absence of Bin1 contributes to growth deregulation in cancer cells in carcinoma of the breast, colon, lung, cervix, prostate and liver.

Otubain 1 (OTUB1) belongs to the ovarian tumor (OUT) superfamily of predicted cysteine proteases and inhibits cytokine gene transcription in the immune system through its interaction with a ubiquitin protease and E3 ubiquitin ligase. OTUB1 is a highly specific ubiquitin iso-peptidase, it cleaves ubiquitin from branched poly-ubiquitin chains but not from ubiquitinated substrates. OTUB1 is believed to work in specific ubiquitin-dependent pathways, possibly by providing an editing function of polyubiquitin chain growth. OTUB1 is a hydrolase that removes conjugated ubiquitin from proteins in vitro and may therefore have a significant regulatory role in the level of protein turnover by preventing degradation. Additionally, OTUB1 is a regulator of T-cell anergy, a phenomenon that occurs when T-cells are rendered impassive to antigen re-challenge and no longer respond to their cognate antigen. OTUB1 acts via its interaction with RNF128/GRAIL, which is an essential inductor of CD4 T-cell anergy.

Synaptotagmin-3 (SYT3) is a member of the synaptotagmin family. SYT3 is involved in Ca(2+)-dependent exocytosis of secretory vesicles through Ca(2+) and phospholipid binding to the C2 domain or may function as Ca(2+) sensors in the process of vesicular trafficking and exocytosis.

BTLA, also known as B & T Lymphocyte Associated, is an inhibitory molecule which is part of the Ig superfamily. BTLA is a type 1 transmembrane glycoprotein in the CD28 family of T cell costimulatory molecules. BTLA is a 3rd inhibitory receptor on T lymphocytes with resemblances to CTLA-4 & PD-1. Moreover, BTLA is a ligand for TNF (receptor) superfamily, TNFRSF14, and HVEM. BTLA-HVEM complexes negatively regulate T-cell immune responses.

Tumor-associated calcium signal transducer 2 (TACSTD2), is a member of to the EPCAM family. TACSTD2 is an intronless gene which encodes a carcinoma-associated antigen. TACSTD2 may act as a growth factor receptor and as a cell surface receptor that transduces calcium signals. Mutations of TACSTD2 have been associated with gelatinous drop-like corneal dystrophy.

FBL is a significant small nucleolar protein in eukaryotes, which has an essential role in pre-rRNA processing during ribosomal biogenesis. Fibrillarin is a component of several ribonucleoproteins including a nucleolar small nuclear ribonucleoprotein (SnRNP) and one of the two classes of small nucleolar ribonucleoproteins (snoRNPs). Fibrillarin contains an N-terminal repetitive domain which is rich in glycine and arginine residues, like fibrillarins in other species. Fibrillarin’s central region is similar to an RNA-binding domain and contains an RNP consensus sequence. FBL is linked to the U3, U8, and U13 small nuclear RNAs and is positioned in the dense fibrillar component (DFC) of the nucleolus. Antisera from roughly 8% of humans with the autoimmune disease scleroderma recognize fibrillarin.

Rat and mouse FGF-9 show a very high homology to human FGF-9. The transcripts for FGF-9 have been found in brain and in kidney tissue. Fibroblast Growth Factor-9 is a member of the fibroblast growth factor (FGF) family. FGF family members possess broad mitogenic and cell survival activities, and are involved in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth and invasion. FGF9 was isolated as a secreted factor that exhibits a growth-stimulating effect on cultured glial cells. In nervous system, this protein is produced mainly by neurons and may be important for glial cell development. Expression of the mouse homolog of this gene was found to be dependent on Sonic hedgehog (Shh) signaling. Mice lacking the homolog gene displayed a male-to-female sex reversal phenotype, which suggested a role in testicular embryogenesis Fibroblast Growth Factor 9 may have a role in glial cell growth and differentiation during development, gliosis during repair and regeneration of brain tissue after damage, differentiation and survival of neuronal cells, and growth stimulation of glial tumors.

Fibroblast growth factor 16 (FGF16) is a member of the large FGF family, whose members are heparin-binding growth factors with a core 120 amino acid (a.a.) FGF domain which allows for a common tertiary structure. Human FGF16 cDNA is a 207 aa precursor protein with one N-linked glycosylation site. FGF16 though lacking a typical signal peptide, is efficiently produced by mechanisms other than the classical protein secretion pathway. FGF16 is expressed in cardiac cells and is required for proper heart development. FGF16 gene mutation was also observed in individuals with metacarpal 4-5 fusion. FGF16 has an imperative role in the regulation of embryonic development, cell proliferation and cell differentiation, and is required for normal cardiomyocyte proliferation and heart development.

Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs). They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4). Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVE supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.

TIMP2 belongs to the TIMP gene family. The proteins encoded by this gene family are natural inhibitors of the matrix metalloproteinases, a group of peptidases that take part in degradation of the extracellular matrix. Besides having an inhibitory role against metalloproteinases, the encoded protein has a exclusive part among TIMP family members in its capability to directly suppress the proliferation of endothelial cells. Consequently, the encoded protein is crucial to the conservation of tissue homeostasis by suppressing the production of quiescent tissues as an answer to angiogenic factors, and by inhibiting protease activity in tissues undergoing renovation of the extracellular matrix.

Cytokeratin 16, also known as KRT16, is a member of the keratin gene family. KRT16 which acts as a regulator of innate immunity in response to skin barrier breach is required for some inflammatory checkpoint for the skin barrier maintenance. KRT16 is coexpressed with keratin 14 in a few epithelial tissues as esophagus, tongue, and hair follicles.

The proteasome is a multicatalytic proteinase complex with an extremely organized ring-shaped 20S core structure. The core structure consists of 4 rings of 28 non-identical subunits; 2 rings consist of 7 alpha subunits and 2 rings consist of 7 beta subunits. Proteasomes are spread all over the eukaryotic cells in large quantities and cleave peptides in an ATP/ubiquitin-dependent procedure in a non-lysosomal pathway. A vital role of a modified proteasome, the immunoproteasome, is the handling of class I MHC peptides.

Clusterin also named Apolipoprotein J (APO-J) is a 75-80 kD disulfide-linked heterodimeric protein containing about 30% of N-linked carbohydrate rich in sialic acid but truncated forms targeted to the nucleus have also been identified.
The precursor polypeptide chain is cleaved proteolytically to remove the 22-mer secretory signal peptide and subsequently between residues 227/228 to generate the a and b chains. These are assembled in anti-parallel to give a heterodimeric molecule in which the cysteine-rich centers are linked by five disulfide bridges and are flanked by two predicted coiled-coil a-helices and three predicted amphipathic a-helices.
Across a broad range of species clusterin shows a high degree of sequence homology ranging from 70% to 80%. It is nearly ubiquitously expressed in most mammalian tissues and can be found in plasma, milk, urine, cerebrospinal fluid and semen.
It is able to bind and form complexes with numerous partners such as immunoglobulins, lipids, heparin, bacteria, complement components, paraoxonase, beta amyloid, leptin and others. Clusterin has been ascribed a plethora of functions such as phagocyte recruitment, aggregation induction, complement attack prevention, apoptosis inhibition, membrane remodeling, lipid transport, hormone transport and/or scavenging, matrix metalloproteinase inhibition.
A genuine function of clusterin has not been defined. One tempting hypothesis says that clusterin is an extracellular chaperone protecting cells from stress induced insults caused by degraded and misfolded protein precipitates.
Clusterin is up- or down regulated on the mRNA or protein level in many pathological and clinically relevant situations including cancer, organ regeneration, infection, Alzheimer disease, retinitis pigmentosa, myocardial infarction, renal tubular damage, autoimmunity and others.

CNTF is a polypeptide hormone whose actions appear to be restricted to the nervous system where it promotes neurotransmitter synthesis and neurite outgrowth in certain neuronal populations. The protein is a potent survival factor for neurons and oligodendrocytes and may be relevant in reducing tissue destruction during inflammatory attacks. A mutation in this gene, which results in aberrant splicing, leads to ciliary neurotrophic factor deficiency, but this phenotype is not causally related to neurologic disease. In addition to the predominant monocistronic transcript originating from this locus, the gene is also co-transcribed with the upstream ZFP91 gene. Co-transcription from the two loci results in a transcript that contains a complete coding region for the zinc finger protein but lacks a complete coding region for ciliary neurotrophic factor.
CNTF is a survival factor for various neuronal cell types. Seems to prevent the degeneration of motor axons after axotomy.

TNFSF15 is a cytokine that belongs to the tumor necrosis factor (TNF) ligand family. This protein is abundantly expressed in endothelial cells, but is not expressed in either B or T cells. The expression of TNFSF15 is inducible by TNF and IL-1 alpha. This cytokine is a ligand for receptor TNFRSF25 and decoy receptor TNFRSF21/DR6. It can activate NF-kappaB and MAP kinases, and acts as an autocrine factor to induce apoptosis in endothelial cells. TNFSF15 is also found to inhibit endothelial cell proliferation, and thus may function as an angiogenesis inhibitor. An additional isoform encoded by an alternatively spliced transcript variant has been reported but the sequence of this transcript has not been determined.

rGFP, also known as Green Fluorescent Protein, is a protein produced by the jellyfish (Aequorea Victoria) that produces bioluminescence in the green zone of the noticeable spectrum. Green Fluorescent Protein is a useful and ubiquitous instrument for producing chimeric proteins, where it functions as a fluorescent protein tag. rGFP is expressed in most known cell types and is used as a noninvasive fluorescent marker in living cells and organisms. Green Fluorescent Protein permits a broad range of applications where it has functioned as a cell lineage tracer, reporter of gene expression, or as a measure of protein-protein interactions.

Regulator of G-protein signaling 5 (RGS5) binds directly to activated G alpha subunits and act as GTPase-activating proteins (GAPs) in order to weaken and/or modulate hormone and neurotransmitter receptor-initiated signaling by both G alpha-GTP and G beta gamma. Vascular endothelial cells express the RGS protein RGS5, where it correlates with capillary morphogenesis, consequently rendering it a candidate gene involved in capillary growth, angiogenesis, and also possibly the pathophysiology of stroke.

Regulation of nuclear pre-mRNA domain-containing protein 1B (RPRD1B) interacts with phosphorylated C-terminal heptapeptide repeat domain (CTD) of the largest RNA polymerase II subunit POLR2A, and participates in dephosphorylation of the CTD. RPRD1B stimulates binding of RNA polymerase II to the CCDN1 promoter and to the termination region before the poly-A site but decreases its binding after the poly-A site. RPRD1B inhibits RNA polymerase II from reading through the 3' end termination site and may allow it to be drafted back to the promoter through promotion of the formation of a chromatin loop. In addition, RPRD1B enhances the transcription of several other cell cycle-related genes including CDK2, CDK4, CDK6 and cyclin-E but not CDKN1A, CDKN1B or cyclin-A. RPRD1B also promotes cell proliferation.