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UBE2L6 belongs to the E2 ubiquitin-conjugating enzyme family. UBE2L6 enzyme is very similar in its primary structure to the enzyme encoded by UBE2L3 gene. UBE2L6 catalyzes the covalent attachment of ubiquitin to other proteins. UBE2L6 functions in the e6/e6-ap-induced ubiquitination of p53/tp53.

Bestrophin 1 (BEST1) is a part of the bestrophin gene family and is also forms calcium-activated chloride-ion channels in epithelial. This small gene family is characterized by proteins with a highly conserved N-terminus with 4-6 transmembrane domains. BEST1 is extremely permeable to bicarbonate.

PQBP1 is a transcription repressor which is connected to polyglutamine tract-containing transcription regulators and connective genes for neurodegenerative disorders. PQBP1 is restricts to the nucleus and can be found in neurons all over the brain, with high levels in hippocampus, olfactory bulb and cerebellar cortex. PQBP1 holds a WWP/WW domain that binds proline-rich motifs and a C2 domain which is able to stimulate Ca2+-dependent phospholipid signaling.

The La protein is a 47 kDa polypeptide that frequently acts as an autoantigen in systemic lupus erythematosus and Sjogren's syndrome patients. La is involved in various aspects of RNA metabolism, including binding and protecting 3-prime UUU(OH) elements of newly RNA polymerase III - transcribed RNA, processing 5-prime and 3-prime ends of pre-tRNA precursors, acting as an RNA chaperone, and binding viral RNAs linked to hepatitis C virus. It occurs in both the nucleus and the cytoplasm, where it assumes different roles. In the nucleus, La protein facilitates the production of tRNAs, acting as an RNA polymerase III (RNAP III) transcription factor by attaching to the U-rich 3'UTR of nascent transcripts, aiding in their folding and maturation. In the cytoplasm, La protein facilitates the translation of specific mRNAs, acting as a translation factor. As an RNA binding protein (RBP), La protein associates with subsets of mRNAs which contain a 5'-terminal oligopyrimidine (5'TOP) motif known to direct protein synthesis. The binding of La protein to particular classes of RNA molecules regulates their downstream processing, guards them from endonuclease digestion, and organizes their export from the nucleus. La/SS-B appears to be readily disposed to proteolysis, which results in many smaller (42kD, 320, and 270) nevertheless still immunoreactive polypeptides. La/SS-B antigen is strongly conserved across species. Anti-La/SS-B autoantibodies were originally found as precipitating autoantibodies in sera of Sjogren's Syndrome patients and referred to as SjT. Anti-La/SS-B precipitins are most frequently found in Sjogren's Syndrome, Systemic Lupus Erythematosus (SLE) and Subacute Cutaneous Lupus. Also, there seems to be a correlation between anti-La/SS-B and the absence of nephritis in SLE patients.

TPRKB is a member of the CGI121/TPRKB family. TPRKB is localized to nucleus and cytoplasm and is ubiquitously expressed. TPRKB is known to cooperate with TP53RK/PRPK.

S100A4 is part of the S100 super-family of proteins containing 2 EF-hand calcium binding domains. S100A4 is ubiquitously overexpressed and is localized in the cytoplasm and/or nucleus. S100A4 is involved in motility, invasion, and tubulin polymerization. Chromosomal rearrangements and altered expression of the S100A4 gene have been implicated in tumor metastasis.

Fibrinogen silencer-binding protein (FSBP), interacts with X11alpha. The X11alpha/FSBP complex send signals to the nucleus in order to repress glycogen synthase kinase-3beta promoter activity. X11alpha is a neuronal adaptor protein that interacts with the amyloid precursor protein (APP) via a centrally located phosphotyrosine binding domain to inhibit the production of Abeta peptide that is deposited in Alzheimer's diseased brains.

The heat-shock response is elicited by exposure of cells to thermal and chemical stress and through the activation of HSFs (heat shock factors) results in the elevated expression of heat-shock induced genes. Heat shock factor binding protein-1 (HSBP1), is a 76-amino-acid protein that binds to heat shock factor 1(HSF1), which is a transcription factor involved in the HS response. During HS response, HSF1 undergoes conformational transition from an inert non-DNA-binding monomer to active functional trimers. HSBP1 is nuclear-localized and interacts with the active trimeric state of HSF1 to negatively regulate HSF1 DNA-binding activity. Overexpression of HSBP1 in mammalian cells represses the transactivation activity of HSF1. When overexpressed in C.elegans HSBP1 has severe effects on survival of the animals after thermal and chemical stress consistent with a role of HSBP1 as a negative regulator of heat shock response.

EIF4EBP1 (eukaryotic translation initiation factor 4E-binding protein 1) belongs to a family of translation repressor proteins. EIF4EBP1 regulates eIF4E (eukaryotic translation initiation factor 4E) activity by preventing its assembly into the eIF4F complex and mediates the regulation of protein translation by hormones, growth factors and other stimuli that signal through the MAP kinase and mTORC1 pathways. EIF4EBP1 is phosphorylated in response to various signals including UV irradiation, resulting in its dissociation from eIF4E and activation of mRNA translation. EIF4EBP1 C-terminus has domains which control function and phosphorylation. EIF4EBP1 has a role in progression of breast neoplasms through cell signaling.

S100 calcium binding protein A5 (S100A5) belongs to the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 family members are localized in the cytoplasm and/or nucleus of a wide range of cells, and are involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. S100A5 has a Ca2+ affinity 20-100 fold higher than the other S100 proteins investigated under identical conditions. Furthermore, S100A5 protein binds Zn2+ and Cu2+, and Cu2+ strongly which harms the binding of Ca2+. S100A5 is expressed in very limited regions of the adult brain.

UBE2K belongs to the ubiquitin-conjugating enzymes family which take part in many cellular processes such as selective protein degradation, DNA repair, cell cycle control, and sporulation. In this mechanism, the ATP-coupled activation and subsequent ligation of ubiquitin are catalyzed by separate enzymes functionally linked by ubiquitin carrier protein UBC1. In addition, UBE2K is involved in Alzheimer's disease, Huntington's disease and antigen processing through its interaction with amyloid-?, huntingtin, and MHC-heavy chain proteins.

Cold inducible RNA-binding protein (CIRBP) has a protective role in the genotoxic stress response by stabilizing transcripts of genes involved in cell survival. CIRBP localizes to the nucleus and contains one RRM (RNA recognition motif) domain. Expressed ubiquitously, CIRBP is believed to play a crucial role in the suppression of cellular proliferation in response to UV irradiation or extreme cold.

VAMP8 also called endobrevin, is the main component of a SNARE complex involved in the docking and fusion of synaptic vesicles with the presynaptic membrane. VAMP8 protein is involved in the regulatation of enzyme secretion in pancreatic acinar cells and plays a part in the abscission of the midbody during cell division, which leads to completely separate daughter cells. VAMP8 is essential for dense-granule secretion in platelets. VAMP8 is related with the perinuclear vesicular structures of the early endocytic compartment. VAMP8 interacts particularly with the soluble NSF-attachment protein (alpha-SNAP), through an VAMP8-containing SNARE complex.

Ubiquitin thioesterase OTUB2 (OTUB2) is a member of the peptidase C65 family. OTUB2 functions as a hydrolase which can remove conjugated ubiquitin from proteins in vitro and may thus play a key regulatory role at the level of protein turnover by preventing degradation.

Sialic Acid Binding Ig Like Lectin 5, also known as SIGLEC5 is a member of the immunoglobulin superfamily and SIGLEC family. SIGLEC5 contains of 2 Ig-like C2-type domains and 1 Ig-like V-type domain. In addition, SIGLEC5 is expressed by monocytic/myeloid lineage cells. SIGLEC5 is expressed at high levels in peripheral blood leukocytes, spleen, and at lower levels in lymph node, appendix, pancreas, lung, and thymus.

Listeriolysin O (aka LLO) is a hemolysin produced by Listeria monocytogenes bacteria, the pathogen responsible for causing listeriosis. The toxin may be regarded as a virulence factor, since it is crucial for the virulence of L. monocytogenes. LLO is a single polypeptide protein encoded by the hlyA gene and composed of 529 residues. LLO is a thiol-activated cholesterol-dependent pore forming toxin protein; therefore, it is activated by reducing agents and inhibited by oxidizing agents. Still, LLO differs from other thiol-activated toxins, as its cytolytic activity is maximized at a pH of 5.5. Inside the acidic phagosomes (average pH ~ 5.9) of cells that have phagocytosed L. monocytogenes, LLO is selectively activated by maximizing activity at a pH of 5.5. Following the phagosome lysis by LLO, the bacterium breaks out into the cytosol, where it is able to grow intracellularly, and the toxin has reduced activity in the more basic cytosol. Thus, LLO permits L. monocytogenes to break out from the phagosomes into the cytosol without harming the plasma membrane of the infected cell, which allows the bacteria to live intracellularly, where they are sheltered from extracellular immune system factors such as the complement system and antibodies. LLO also brings about dephosphorylation of histone H3 and deacetylation of histone H4 in the early phases of infection, before entry of L. monocytogenes into the host cell. The pore-forming activity is not implicated in causing the histone modifications. The modifications of the histones affect the down regulation of genes encoding proteins involved in the inflammatory response. Therefore, LLO may be significant in subverting the host immune response to L. monocytogenes. At its NH2-terminus it possesses a 25 residues long typical signal sequence excited during the secretion process. Moreover, in its NH2-terminus there is also a 19 amino acids PEST- like sequence that may target this toxin for degradation. The PEST-like sequence found in LLO and is considered crucial for virulence, given that mutants lacking the sequence lysed the host cell. Nevertheless, contrary to PEST's supposed role in protein degradation, evidence implies that the PEST-like sequence may control LLO production in the cytosol rather than increase degradation of LLO.

CHD4 is a member of a family of alleged chromodomain helicase-DNA-binding proteins. Biochemically, CHD4 is a component of the nucleosome transformation and deacetylase (NuRD) complex that takes part in transcription regulation. Autoantibodies targeting the CHD4 are a serologic feature of idiopathic inflammatory myopathies (IIM). In IIM Mi-2 antibodies are characterized by diagnostic sensitivity and specificity of approximately 4-18% and 98-100%, respectively. Moreover, anti-CHD4 antibodies are related to dermatomyositis (frequency up to 31%) and have a great positive predictive value for this type of disease subset. Anti-CHD4 are the only defined myositis-specific autoantibodies clearly focused to a nuclear target. An additional slightly outstanding feature of Mi-2 antibodies relates to their frequency in children, which is similar to that in adults.

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.

Vps20-associated 1 homolog (VTA1) is a member of the VTA1 family. The VTA1 protein is involved in the endosomal multivesicular bodies (MVB) pathway. Furthermore, VTA1 is interacts with CHMP1B, CHMP2A, CHMP5, VPS4B, KIAA0174 (IST1) and possibly CHMP3. VTA1 is believed to be a cofactor of VPS4A/B, which catalyzes membrane-associated ESCRT-III assemblies. In addition, VTA1 is involved in the sorting and down-regulation of EGFR and also in HIV-1 budding.

The protein encoded by this gene is a member of the bone morphogenetic protein family which is part of the transforming growth factor-beta superfamily. The superfamily includes large families of growth and differentiation factors. Bone morphogenetic proteins were originally identified by an ability of demineralized bone extract to induce endochondral osteogenesis in vivo in an extraskeletal site. This particular family member plays an important role in the onset of endochondral bone formation in humans, and a reduction in expression has been associated with a variety of bone diseases, including the heritable disorder Fibrodysplasia Ossificans Progressiva. Alternative splicing in the 5' untranslated region of this gene has been described and three variants are described, all encoding an identical protein.

FABP6 also called ileal fatty acid binding protein, is part of the small family of highly conserved, cytoplasmic proteins that bind long-chain fatty acids and other hydrophobic ligands. FABP6 cytosolic protein binds bile acid. FABP6 plays a role in fatty acid uptake, transport, and metabolism. FABP6 stimulates gastric acid and pepsinogen secretion. Seems to be able to bind to bile salts and bilirubins. FABP6 expression is restricted in the small intestine to the ileum where it is involved in the enterohepatic circulation of bile acids. Alternate transcription promoters generate 2 transcript variants, encoding a 128 aa and a 177 aa residue protein. Human FABP6 isoform 2 contains 128 amino acid residues and is acetylated on Ala2. FABP6 binds together fatty acids and bile acids and is directly involved in fatty acid transport and metabolism.

S100A6 is a member of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized either in the cytoplasm or the nucleus of a wide range of cells. S100 proteins are involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. There are at least 13 members in the S100 gene family, which are located as a cluster on chromosome 1q21.
S100A6 may function in stimulation prolactin secretion, and exocytosis. Chromosomal rearrangements and altered expression of the S100A6 gene are implicated in melanoma.

Nucleobindin-2 (NUCB2) is a EF-hand calcium-binding protein. Nucleobindin-2 takes part in calcium homeostasis and is a multifunctional protein that interacts with Ca(2+) nucleic acids & various regulatory proteins in different signaling pathways. NUCB2 is localized in neuronal perikarya and dendrites of mouse brain.

Ras-related GTP binding C (RRAGC) is a monomeric guanine nucleotide-binding protein, or G protein. As a result of binding GTP or GDP, small G proteins act as molecular regulators in various cell processes and signaling pathways. RRAGC regulates the organization of the actin cytoskeleton and has an intrinsic GTPase activity. RRAGC is possibly necessary for the amino acid-induced relocalization of mTORC1 to the lysosomes and its succeeding activation by the GTPase RHEB, which is key step in the activation of the TOR signaling cascade by amino acids.