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Ubiquitin Conjugating Enzyme E2Q2 (UBE2Q2) is a protein coding gene which receives ubiquitin from the E1 complex and catalyzes its covalent attachment to various proteins. UBE2Q2 which is a part of the ubiquitin-conjugating enzyme family is detected in hypopharyngeal head and neck squamous cell carcinoma and in tumor masses.

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.

Microtubule-associated protein tau (MAPT or Tau) is a protein that stabilizes microtubules. MAPT is abundant in neurons in the central nervous system and is less common elsewhere. When MAPT is defective, and no longer stabilizes microtubules properly, it can result in dementias, such as Alzheimer's disease.

The ribosomal phosphoproteins, also called P protein antigens, are associated with the large ribosomal subunit and therefore are antigenic targets with a cytoplasmic localization. Three P proteins have been described: P0 with a molecular weight of 35 kDa, P1 (19 kDa) and P2 (17 kDa). RPLP0 is a ribosomal protein that is a component of the 60S subunit. RPLP0 belongs to the L10P family of ribosomal proteins. RPLP0 is a neutral phosphoprotein having a C-terminal end that is nearly identical to the C-terminal ends of the acidic ribosomal phosphoproteins P1 & P2. The P0 protein interacts with P1 and P2 to form a pentameric complex consisting of P1 and P2 dimers, and a P0 monomer. As is typical for genes encoding ribosomal proteins, there are multiple processed pseudogenes of RPLP0 scattered throughout the genome.
Autoantibodies against ribosomal P proteins are present in 10 % of SLE patients. If anti-ribosomal P antibodies were to occur in the absence of other typical SLE associated autoantibodies, they may account for some patients with so-called ANA-negative lupus. It has been reported that lupus patients positive for anti-ribosomal P autoantibodies have a high frequency of CNS involvement, suggesting a marker use for these antibodies.

Podoplanin is a small mucin-like type-1 transmembrane protein, typically expressed in various specialized cell types throughout the body. Podoplanin is a type-I integral membrane glycoprotein with diverse distribution in human tissues. PDPN physiological function is related to its mucin-type character. The homologous protein in other species has been described as a differentiation antigen and influenza-virus receptor.
PDPN is expressed in lymphatic progenitor cells and afterwards during mouse development in lymphatic endothelial cells. Podoplanin is a specific marker for lymph vessel endothelial cells. Over-expression of podoplanin significantly elevates endothelial cell adhesion, migration, and tube formation. Inhibition of Podoplanin expression decreases cell adhesion in human dermal lymphatic endothelial cells. Podoplanin is used as a specific marker for lymphatic endothelium in histopathology.
Podoplanin expression is increased in nearly all human colon, rectum, and small intestine tumors. AGGRUS may serve as a diagnostic marker that distinguishes seminomas, the majority of which over express the protein, from embryonal carcinoma in testicular germ cell tumors.

Ubiquitin-conjugating enzyme E2S (UBE2S) belongs to the ubiquitin-conjugating enzyme family. UBE2S is able to form a thiol ester linkage with ubiquitin in a ubiquitin activating enzyme-dependent manner, a typical property of ubiquitin carrier proteins. UBE2S catalyzes the covalent attachment of ubiquitin to other proteins. UBE2S acts as a crucial factor of the anaphase promoting complex/cyclosome (APC/C), which is a cell cycle-regulated ubiquitin ligase that controls progression through mitosis. UBE2S acts by purposely elongating ''Lys-11''-linked polyubiquitin chains initiated by the E2 enzyme UBE2C/UBCH10 on APC/C substrates, augmenting the degradation of APC/C substrates by the proteasome and promoting mitotic exit. UBE2S also acts by elongating ubiquitin chains initiated by the E2 enzyme UBE2D1/UBCH5 in vitro; it is nevertheless uncertain whether UBE2D1/UBCH5 acts as an E2 enzyme for the APC/C in vivo. UBE2S is also involved in ubiquitination and consequent degradation of VHL, resu

Interleukin 34 (IL34) is a cytokine that promotes the differentiation and viability of monocytes and macrophages through the colony-stimulating factor-1 receptor and is a part of a group of cytokines called interleukins. IL34 increases growth or survival of immune cells known as monocytes. IL34 protein obtains its activity by binding the Colony stimulating factor 1 receptor. Interleukin 34 has also a potential part in viral infection, the adaptive immune response and bone marrow cell proliferation. Furthermore, IL34 plays an important role in innate immunity and in inflammatory processes.

The conserved 76 amino acid protein ubiquitin (Ub) regulates a host of intracellular processes through its enzymatic conjugation to other cellular proteins.
Ubiquitination occurs through sequential steps catalyzed by activating (E1), conjugating (E2), and ligase (E3) enzymes. The final step results in the formation of an isopeptide bond between Ub’s C-terminal glycine residue (G76) and a lysine residue of the target protein, although N-terminal ubiquitination is also known.
Outcomes of this modification include destabilization of the conjugated protein, altered protein trafficking and functional modulation.
After targeting the protein for specific localizations, ubiquitin is released from the substrate by deubiquitinating enzymes.
A mutant ubiquitin, having a Gly to Ala substitution at the C-terminus (G76A ubiquitin) supported several downstream reactions of the proteolytic pathway but inhibits the deubiquitination process.
As consequence, the Ub derivative becomes irreversibly conjugated to protein, shifting the equilibrium between the bound and unbound form in the direction of conjugation, at the expense of the free form.

Phospholipase A1 Member A (PLA1A) is a phospholipase which hydrolyzes fatty acids at the sn-1 position of phosphatidylserine and 1-acyl-2-lysophosphatidylserine. The secreted PLA1A protein hydrolyzes phosphatidylserine in liposomes. PLA1A hydrolyzes phosphatidylserine (PS) in the form of liposomes and 1-acyl-2 lysophosphatidylserine (lyso-PS), but not triolein, phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidic acid (PA) or phosphatidylinositol (PI). PLA1A isoform 2 hydrolyzes lyso-PS but not PS. The hydrolysis of lyso-PS in peritoneal mast cells activated by receptors for IgE leads to stimulation of histamine production.

Cytohesin-interacting protein, also known as CYTIP contains 2 leucine zipper domains as well as a putative C-terminal nuclear targeting signal. However, CYTIP does not contain any hydrophobic regions. In addition, CYTIP is expressed weakly in resting NK and T cells. It also modulates the activation of ARF genes by CYTH1.

Dynein Axonemal Light Intermediate Chain1 also known as DNALI1 belongs to the inner dynein arm light chain family. DNALI1 take a dynamic role in flagellar motility. DNALI1 is the human homolog of the Chlamydomonas inner dynein arm gene, p28. The exactfunction of DNALI1 is not known yet, on the other hand, it is a potential candidate for immotile cilia syndrome. In addition it has been found that the following diseases: primary ciliary dyskinesia, and huntington's disease have been associated with DNALI1. Ultrastructural defects of the inner dynein arms are seen in patients with ICS. Immotile mutant strains ofChlamydomonas, biflagellated algae, show similar defects.

Rho GDP-dissociation inhibitor 1 (ARHGDIA) is a member of the RAS gene superfamily, which encodes small guanine nucleotide exchange (GTP/GDP) factors. ARHGDIA, which is localized to the cytoplasm, inhibits the dissociation of GDP from Rho proteins, thus preventing GTP from binding to and consequently activating Rho proteins. In humans, the ARHGDIA can be phosphorylated at Ser 101 by p21-activated kinase, an event that inhibits its activity and may result in positive feedback regulation of several ARHGDIA target proteins.

Secreted Protein Acidic & Rich in Cysteine (SPARC) protein is coded by the SPARC gene in humans. SPARC is a glycoprotein located in bones that binds to calcium. SPARC is produced by fibroblasts, capillary endothelial cells, platelets and macrophages, mainly in areas of tissue morphogenesis and remodelling. Asides from calcium, SPARC can also bind to collagen.

Eukaryotic translation initiation factor 4H (EIF4H) is a 248 amino acid protein which localizes to the perinuclear region of the cytoplasm and is expressed as 2 isoforms, termed short and long. EIF4H functions to stimulate the initiation of protein synthesis at the level of mRNA employment. EIF4H stimulates the RNA-dependent ATP hydrolysis catalyzed by EIF4A and EIF4B. EIF4H gene defects linked to Williams- Beuren syndrome (WBS), a rare developmental disorder characterized by cardiovascular and musculo-skeletal abnormalities and caused by the deletion of contiguous genes at 7q11.23.

STUB1, is a cytoplasmic protein whose amino acid sequence is highly preserved across species. STUB1 interacts with the molecular chaperones Hsc70-Hsp70 and Hsp90 through its TPR domain, whereas its U-box domain contains its E3 ubiquitin ligase activity. STUB1 interaction with these molecular chaperones lead to in client substrate ubiquitylation and degradation by the proteasome. therefore, STUB1 acts to tilt the folding-refolding mechanism towards the degradative pathway, and it serves as a link between the two. STUB1 inhibits anchorage-independent cell growth and metastatic potential by degrading oncogenic proteins including SRC-3. Inhibition of tyrosine kinase activity of Her-2/neu by quercetin specifies an lateration in the Her-2/neu structure which promotes STUB1 recruitments and down-regulation of Her-2/neu. STUB1 recognizes and mediates degradation of toxic, oligomeric forms of alphaSyn.

C17orf103 is a member of the GTLF3B family and is encoded by a gene which is located in human chromosome 17p11.2. BRCA1 and p53 are 2 main tumor suppressor genes which are linked to chromosome 17. Tumor suppressor p53 is necessary for maintenance of cellular genetic integrity by moderating cell fate through DNA repair versus cell death. C17orf103 is also related to neurofibromatosis, a disorder characterized by neural and epidermal lesions, and dysregulated Schwann cell growth.

Transgelin 2 (TAGLN2) is one of the earliest markers of differentiated smooth muscle. TAGLN2 contains a calponin like repeat and a calponin-homology (CH) domain. TAGLN2 is downregulated in some transformed cell lines, indicating that a reduction of transgelin expression may be an early indicator of the onset of transformation. TAGLN2 also binds actin, causing actin fibers to gel within minutes of binding. The binding of transgelin to actin occurs at a ratio of 1:6 actin monomers.

Calcyphosine (CAPS) is a calcium-binding protein containing four EF-hand domains. CAPS protein was originally identified as thyroid protein p24 which is found in a number of epithelium and in some cells of the central nervous system. CAPS may have a role in the regulation of ion transport. In the thyroid follicular cells, CAPS is synthesized and phosphorylated in response to stimulation by thyrotropin and cAMP agonists.

Frataxin is a mitochondrial iron binding protein that is part of the FRATAXIN family. Frataxin functions in regulating mitochondrial iron transport and respiration. The expansion of intronic trinucleotide repeat GAA results in Friedreich ataxia. Frataxin plays a role in iron homeostasis. Frataxin is an anti-apoptotic protein which prevents mitochondrial damage and reactive oxygen species (ROS) production.

Glycoprotein-9 (GP9) is a small membrane glycoprotein found on the surface of human platelets. GP9 forms a one to one noncovalent complex with glycoprotein Ib, a platelet surface membrane glycoprotein complex which functions as a receptor for von Willebrand factor. The complete receptor complex includes noncovalent association of the alpha and beta subunits with the protein and platelet glycoprotein V. GP9 gene defects cause the Bernard-Soulier syndrome, aka giant platelet disease whose patients have unusually large platelets and have a clinical bleeding tendency.

LSM3 is a member of snRNP Sm proteins family which were identified in a large number of organisms based on sequence homology. Sm-like proteins have a Sm sequence motif that holds 2 regions detached by a linker of variable length that fold as a loop. The Sm-like proteins form a stable heteromer found in tri-snRNP particles that are vital for pre-mRNA splicing.

UCN119B is a member of the PDE6D/unc-119 family. UCN119B has a large number of photoreceptors of the retina. Additionaly, UCN119B has a strong homology with the C. elegans unc119 and is able to functionally complement the C. elegans unc119 mutation gene.

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.