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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.

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.

Charged multivesicular body protein 3 (VPS24/CHMP3) is a member of the vacuolar sorting protein family and function as chromatin modifying proteins. VPS24 links directly with CHMP2 and CHMP4 for the disassembly of ESCRT-III complex in an ATP-dependent manner. During HIV-1 infection, the virus uses the ESCRT-III complex to mediate budding and exocytosis of viral proteins. VPS24 overexpression strongly hinders HIV-1 release.

Peptidase Inhibitor 16 (PI16) which a member of the CRISP family, is a putative serine protease inhibitor. PI16 interacts with PSP94/MSMB. PI16 is expressed in the prostate, testis, ovary and intestine. It also concentrates in prostate cancer patient's sera. PI16 may serve as a marker following prostatectomy for prostate cancer.

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.

Intein is a section of a protein which can remove itself and return the remaining segment with a peptide bond. In addition, Inteins hold an endonuclease domain which takes part in Intein proliferation. Actually, various genes have unrelated intein-coding segments inserted at altered positions and they were found in all three domains of life (eukaryotes, bacteria, and archaea) and in viruses.

"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."

PDCD1 is a cell surface membrane protein of the immunoglobulin superfamily. PDCD1 is expressed in pro-B-cells and is thought to have a role in their differentiation. In mice, expression of PDCD1 gene is induced in the thymus when anti-CD3 antibodies are injected and large numbers of thymocytes undergo apoptosis. Mice deficient for the PDCD1 gene bred on a BALB/c background developed dilated cardiomyopathy and died from congestive heart failure. These studies suggest that the PDCD1 gene product may also be important in T cell function and contribute to the prevention of autoimmune diseases.

Calcium-binding protein 7 (CABP7) contains 2 EF-hand domains. CABP7 negatively regulates Golgi-to-plasma membrane trafficking by interacting with PI4KB and inhibiting its activity. The CaBP family of EF-hand containing small Ca (2+)-binding proteins has lately emerged as significant regulators of multiple targets essential to normal neuronal function in the mammalian central nervous system.

MCP-5 (CCL12) is a cloned mouse CC chemokine most closely related to human MCP1 (66% amino acid sequence identity in the mature protein). MCP5 is expressed constitutively in the thymus and the lymph nodes. Under inflammatory conditions, moreover CCL12 expression is induced in activated macrophages and mast cells. The mouse MCP1 gene is mapped to the CC chemokine cluster on chromosome 11. Recombinant CCL12 is a potent chemoattractant for monocytes and lymphocytes but not neutrophils. At high concentrations, MCP-5 also chemoattracts eosinophils. CCL12 is a functional ligand for CCR2.

Fibroblast growth factor 18 (FGF18) is a member of the large FGF family which has at least 23 members. FGF18 is a binding growth factor with a core 120 amino acid FGF domain which allows for a common tertiary structure. FGFs are expressed in the course of the embryonic development and in restricted adult tissues. FGF-18 is an indispensable regulator of long bone and calvarial development. FGF-18 signals via FGFR 1c, 2c, 3c, and 4.

Bcl-2–associated X protein (Bax) belongs to the Bcl-2 protein family. Bax is a pro-apoptotic Bcl-2 protein containing BH1, BH2 and BH3 domains. Bax accelerates programmed cell death by binding to, and antagonizing the apoptosis repressor bcl2 or its adenovirus homolog e1b 19k protein. Bax induces the release of cytochrome c, activation of casp3, and thereby apoptosis. Bax is expressed in a wide variety of tissues, with highest levels in the testis and ovary. Tumor suppressor protein p53 upregulates the expression of BAX. Bax has been shown to be involved in p53-mediated apoptosis.

Sperm Antigen With Calponin Homology And Coiled-Coil 1 (SPECC1) which is a part of the cytospin-A family takes part in cytokinesis and spindle organization. SPECC1 takes part in actin cytoskeleton organization and microtubule stabilization and therefore necessary for proper cell adhesion and migration.

LAT is a vital membrane protein that is phosphorylated by ZAP-70/Syk protein tyrosine kinases succeeding activation of the T-cell antigen receptor (TCR) signal transduction pathway. LAT is expressed in T lymphocytes in interstitial spaces, platelets and megakaryocytes.

RAB14 belongs to the RAB protein family, low molecular mass monomeric GTPases which is found on the cytoplasmic surfaces of distinct membrane bound organelles. RAB14 has a role in vesicular trafficking and neurotransmitter release throughout the body and is expressed at high levels in brain, lung, kidney, spleen and thymus. In addition, RAB14 takes part in the biosynthetic/recycling pathway between the Golgi and endosomal compartments.

The 26S proteasome is a multicatalytic proteinase complex with a well ordered structure composed of two complexes- a 20S core and a 19S regulator. PSMD11 is a non-ATPase subunit of the 19S regulator. The 20S core is composed of four rings of 28 non-identical subunits; two rings are composed of 7 alpha subunits and two rings are composed of 7 beta subunits. The 19S regulator is composed of a base that contains six ATPase subunits and two non-ATPase subunits, and a lid that contains up to ten non-ATPase subunits. Proteasomes are spread throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. An indispensable function of a modified proteasome, the immunoproteasome, is the processing of class I MHC peptides.

SERPINH1 is part of the serpin superfamily of serine proteinase inhibitors. SEPINH1 expression is induced by heat shock. HSP47 localizes to the endoplasmic reticulum lumen and binds collagen therefore it is a molecular chaperone which takes part in the maturation of collagen molecules, facilitating the folding and assembly of procollagen molecules, retaining unfolded molecules within the ER, and assisting the transport of correctly folded-molecules from the ER to Golgi apparatus. Autoantibodies to HSP47 protein have been found in rheumatoid arthritis. SERPINH1 binds specifically to collagen and acts as a chaperone in the biosynthetic pathway of collagen.

SH3-domain GRB2-like 2 (SH3GL2) is a member of the endophilin family. SH3GL2 contains a BAR domain and a SH3 domain. Members of the BAR domain protein superfamily are crucial elements of cellular traffic. Endophilins have a major function in synaptic vesicle endocytosis (SVE), receptor trafficking and apoptosis, and in other processes which require remodeling of the membrane structure. SH3GL2 is a novel tumor suppressor gene in laryngeal squamous cell carcinoma (LSCC), which induces apoptosis of tumor cells by regulating intra-cellular signal transduction networks. SH3GL2 is implicated in synaptic vesicle endocytosis. SH3GL2 is found in the brain, mainly in frontal cortex, and at high level in the fetal cerebellum.

ARL15 is a member of the ARF family which are essential in eukaryotic vesicular trafficking pathways and have a vital part in the activation of phospholipase D. ARL15 variants influence levels of Acrp30, an adipocyte-derived protein that is extremely genetic and inversely related to the prospect of type 2 diabetes mellitus and coronary heart disease.

TREM1 is a transmembrane receptor protein that is involved in monocytic activation and in the inflammatory response. TREM1 is expressed on the surface of neutrophils, mature monocytes and macrophages. TREM1 stimulates neutrophil and monocyte-mediated inflammatory responses. TREM1 also triggers the release of pro-inflammatory chemokines and cytokines, as well as increased surface expression of cell activation markers. Furthermore, TREM1 is an amplifier of inflammatory responses that are triggered by bacterial and fungal infections and is a fundamental mediator of septic shock. The expression of the soluble form of TREM1 increases during sepsis and can consequently be used as a biological marker for septic shock. TREM1 is strongly expressed in acute inflammatory lesions caused by bacteria and fungi. Increased TREM1 expression on monocytes is related to both infectious and noninfectious inflammatory processes.
TREM1 is vastly expressed in adult liver, lung and spleen than in corresponding fetal tissue. TREM1 is also expressed in the lymph node, placenta, spinal cord and heart tissues. TREM1 expression is more elevated in peripheral blood leukocytes than in the bone marrow and in normal cells than malignant cells. TREM1 is expressed at low levels in the early development of the hematopoietic system and in the promonocytic stage and at high levels in mature monocytes.

Synaptobrevin 2 which is an 18 kDa integral membrane protein localized to the cytoplasmic surface of synaptic vesicle, consists of a proline-rich N-terminal region, a highly conserved hydrophilic domain, followed by a transmembrane anchor and a C-terminal. Synaptobrevin 2 is predominantly expressed in Langerhans islets and glomerular cells. The N-terminal domain of the protein (residues 1-89) forms a specific SNARE complex with the target membrane-associated t- or Q-SNAREs syntaxin 1 and SNAP-25.

MAP1LC3A takes part in formation of autophagosomal vacuoles and is one of the light chain subunits that functions together with both MAP1A and/or MAP1B. MAP1LC3A has an important part in neuronal development and in maintaining the balance between neuronal plasticity and rigidity. MAP1LC3A is expressed as two alternatively spliced isoforms that are expressed in testis, brain, heart, liver and skeletal muscle, but are absent in thymus and peripheral blood leukocytes.

NME2 takes an important part in the synthesis of nucleoside triphosphates other than ATP. NME2 negatively controls Rho activity by interacting with AKAP13/LBC. NME2 acts as a transcriptional activator of the MYC gene. NME2 binds DNA non-specifically. NME2 is a heterodimeric enzyme functioning as a nucleoside diphosphate kinase. NME1 and NME2 contain 152 amino acids, A and B polypeptide chains of the NM23 enzyme, respectively. NME2 is identical to the beta subunit of human erythrocyte NDP kinase. NDP kinases participate in the synthesis of nucleoside triphosphates, and NM23 is involved in the regulation of signal transduction by complexing with G proteins, causing activation/inactivation of developmental pathways.