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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.

Prosaposin (PSAP) is a precursor of 4 lysosomal saposin proteins (saposin A, B, C and D). Saposins are heat-stable glycoproteins which facilitate the catabolism of glycosphingolipids with short oligosaccharide groups. PSAP stimulates neurite outgrowth and increases choline acetyltransferase activity. Prosaposin exists both as a secretory protein and as an integral membrane protein and has neurotrophic activities. The secreted prosaposin is assumed to have additional functions in human milk, cerebrospinal fluid and seminal plasma. PSAP gene mutations are linked with Gaucher disease, Tay-Sachs disease, and metachromatic leukodystrophy.

Human TNFRSF10A is a type 1 transmembrane protein in the TNF R superfamily. TNFRSF10A is not expressed in rodents. The trimeric ligand Trail binds TNFRSF10A and induces apoptosis, and recombinant, soluble forms of the receptor inhibit Trail-induced apoptosis. TNFRSF10A is expressed generally in damaged, infected, and malignant cells. TNFRSF10A functions in immune surveillance, inducing apoptosis in cancer cells but not normal cells.

SNAP-25 is an necessary element of the core complex that is responsible for presynaptic vesicle trafficking. Thus, SNAP-25 is directly involved in the release of neurotransmitters and this protein exists as two alternative isoforms, SNAP25A and SNAP25B which differ by 9 amino acids in central portion of these proteins.

Neurexophilin 1 (NXPH1) is a part of the neurexophilin family which encodes a secreted protein with a variable N terminal domain, an extremely conserved, N-glycosylated central domain, a short linker region, and a cysteine-rich Cterminal domain. NXPH1 shapes a very tight complex with alpha neurexins, a group of proteins which promote adhesion among dendrites and axons.

NGF-beta has nerve growth stimulating activity and the complex is involved in the regulation of growth and the differentiation of sympathetic and certain sensory neurons. Mutations in this gene have been associated with hereditary sensory and autonomic neuropathy, type 5 (HSAN5), and dysregulation of this gene's expression is associated with allergic rhinitis. Nerve Growth Factor was the 1st protein found from the family of neurotrophic factors that influence the growth and differentiation of sympathetic and sensory neurons. NGF consists of 3 different subunits: alpha, beta, and gamma. The beta subunit is accountable for its growth stimulating activity. The synthesis of NGF in astrocytes is enhanced by a range of cytokines such as IL1, TNF-a, PDGF & TGF-b.

Syntaxin-binding protein 6 (STXBP6) binds components of the SNARE complex and takes part in regulating SNARE complex configuration. STXBP6 forms non-fusogenic complexes with SNAP25 and STX1A and modulates the formation of SNARE complexes and exocytosis.

SYT13 belongs to the great synaptotagmin protein family which contain 2 domains: cytoplasmic C terminus with two tandem C2 domains (C2A and C2B) and extracellular N-terminal transmembrane domain. Synaptotogmin family members have dissimilar biochemical properties and developmental profiles, and patterns of tissue distribution. Additionally, Synaptotogmins formulate homo- and heteromeric complexes with each other. Synaptotagmins operate as membrane traffickers in multicellular organisms.

CRP is an acute phase protein that correlates with inflammatory disease and is synthesized by hepatocytes during the acute phase response by certain cytokines (IL-1 and TNF Alpha and Beta). CRP levels increase dramatically and serve as a useful marker of inflammation in such conditions as bacterial infection, rheumatoid arthritis, viral infections, transplantation rejection, meningitis, myocardial infarction, septicemia, osteomyelitis and others. CRP is also highly correlated to Serum Amyloid A levels.

Adiponectin is a recently discovered 244 amino acid protein, the product of the apM1 gene, which is physiologically active and specifically and highly expressed in adipose cells (Adipokine). The protein belongs to the soluble defense collagen super family; it has a collagen-like domain structurally homologous with collagen VIII and X and complement factor C1q-like globular domain. APM-1 forms homotrimers, which are the building blocks for higher order complexes found circulating in serum.

Neudesin Neurotrophic Factor (NENF) is a member of the cytochrome b5 family, MAPR subfamily. NENF contains 1 cytochrome b5 heme-binding domain. NENF exhibits neurotrophic activity and activates phosphorylation of MAPK1/ERK2, MAPK3/ERK1 and AKT1/AKT in primary cultured neurons. NENF doesn’t have mitogenic activity in primary cultured astrocytes. NENF may play a part in neuronal differentiation and may have a transient influence on neural cell proliferation in neural precursor cells. NENF neurotrophic activity is increased by binding to heme. NENF is up-regulated in immortal cells and induced in estrogen receptor positive breast cancer expressing progesterone receptor.

Nucleopurin 62kDa (NUP62) belongs to the FG-repeat containing nucleoporins and is localized to the nuclear pore central plug. Nucleoporins are the principal components of the nuclear pore complex in eukaryotic cells. This complex is a colossal structure which extends across the nuclear envelope, forming an entryway that regulates the stream of macromolecules between the nucleus and the cytoplasm. NUP62 associates with the importin alpha/beta complex that is involved in the import of proteins containing nuclear localization signals. Defects in the NUP62 are the cause of SNDI (infantile striatonigral degeneration), aka infantile bilateral striatal necrosis (IBSN) or familial striatal degeneration.

The bone morphogenetic protein (BMP) receptors are a family of transmembrane serine/threonine kinases that include the type I receptors BMPR1A and BMPR1B and the type II receptor BMPR2. These receptors are also closely related to the activin receptors, ACVR1 and ACVR2. The ligands of these receptors are members of the TGF-beta superfamily. TGF-betas and activins transduce their signals through the formation of heteromeric complexes with 2 different types of serine (threonine) kinase receptors: type I receptors of about 50-55 kD and type II receptors of about 70-80 kD. Type II receptors bind ligands in the absence of type I receptors, but they require their respective type I receptors for signaling, whereas type I receptors require their respective type II receptors for ligand binding.

Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit. Mitochondrial Ribosomal Protein S28, also known as MRPS28, is a protein coding gene which encodes a 28S subunit protein which is known as mitochondrial ribosomal protein S35.

Heterogeneous nuclear ribonucleoprotein A1 (HNRNPA1) is a member of the A/B subfamily of ubiquitously expressed heterogeneous nuclear ribonucleoproteins (hnRNPs). HNRNPA1 is involved in the packing of pre-mRNA into hnRNP particles, transport of poly(A) mRNA from the nucleus to the cytoplasm and may control splice site selection. The HNRNPA1 protein may also have a role in HCV RNA replication. In addition, HNRNPA1 is believed to have a key role in the formation of specific myometrial protein species in parturition.
The hnRNP proteins have distinctive nucleic acid binding properties. HNRNPA1 has 2 repeats of quasi-RRM domains that bind to RNAs. HNRNPA1 is one of the most copious core proteins of hnRNP complexes and it is restricted to the nucleoplasm. The HNRNPA1 protein, along with other hnRNP proteins, is exported from the nucleus, most likely bound to mRNA, and is immediately re-imported. The M9 domain of HNRNPA1 functions as both a nuclear localization and nuclear export signal.

Gamma-SNAP (NAPG) is a cytoplasmic protein which binds to a membrane receptor complex composed of VAMP, SNAP25 and syntaxin. NAPG mediates the membrane binding of NSF, which is crucial for membrane fusion reactions. NSF and SNAPs seem to be general components of the intracellular membrane fusion system, and their action at specific sites of fusion needs be controlled by SNAP receptors specific to the membranes being fused. NAPG mediates platelet exocytosis and controls the membrane fusion events of this process.

Sarcoglycan Beta, also known as SGCB, is a part of the sarcoglycan family. SGCB belongs to the sarcoglycan complex which is a subcomplex of the dystrophin-glycoprotein complex that connects between the F-actin cytoskeleton and the extracellular matrix.

a-Synuclein (amino acids 1-140), an acidic neuronal protein of 140 amino acids, is extremely heat-resistant and is natively unfolded with an extended structure primarily composed of random coils. a-synuclein has been suggested to be implicated in the pathogenesis of Parkinson’s disease and related neurodegenerative disorders, and more recently, to be an important regulatory component of vesicular transport in neuronal cells. Moreover, recent studies have shown that a-synuclein has chaperone activity and that this activity is lost upon removing its C-terminal acidic tail (amino acids 96-140).

NRTN belongs to the GDNF family of ligands, a distant member of the TGF-beta superfamily. NRTN, a ligand used to bind to GFRA2 receptors, signals through RET and a GPI-linked coreceptor, and promotes endurance of neuronal populations, controls the size of non-neuronal cell population such as haemopoietic cells and regulate the development and maintenance of the CNS. Mutation in NRTN results in Hirschsprung Disease.

NSMCE1 is a component of the SMC5-SMC6 complex, a complex involved in DNA double-strand breaks by homologous recombination. The complex may promote sister chromatid homologous recombination by recruiting the SMC1-SMC3 cohesin complex to double-strand breaks. The complex is required for telomere maintenance via recombination in ALT (alternative lengthening of telomeres) cell lines and mediates sumoylation of shelterin complex (telosome) components which is proposed to lead to shelterin complex disassembly in ALT- associated PML bodies (APBs). NSMCE1 has in vitro ubiquitin ligase activity in presence of NDNL2.

Natriuretic Peptide Precursor B acts as a cardiac hormone with a variety of biological actions including natriuresis,vasorelaxation,diuresis and inhibition of renin and aldosterone secretion. BNP plays a key role in cardiovascular homeostasis. BNP also helps restore the body's salt and water balance andimproves heart function.

Cytosolic Fe-S cluster assembly factor NUBP1 isoform 1 (NUBP1) is Involved in the regulation of centrosome duplication similarity. NUBP1 is a component of the cytosolic iron-sulfur (Fe/S) protein assembly (CIA) machinery. NUBP1 is necessary for maturation of extra mitochondrial Fe-S proteins. The NUBP1-NUBP2 heterotetramer constructs a Fe-S scaffold complex, mediating the de novo compilation of a Fe-S cluster and its transfer to target apoproteins.

Oxidative Stress Responsive 1, also known as OXSR1 belongs to the neuronal calcium sensor gene family. OXSR1 encodes calcium-binding proteins which expressed mainly in neurons and regulates G protein-coupled receptor phosphorylation in a calcium-dependent way. OXSR1 regulates downstream kinases in response to environmental stress and functions in regulating the actin cytoskeleton.

TRAIL Receptor-3, also known as TNFRSF10C belongs to theTNF-receptor super family. TNFRSF10C contains an extracellular TRAIL-binding domain as well as a transmembranedomain, however no cytoplasmic death domain. Furthermore, TNFRSF10C is not capable of inducing apoptosis, and is considered toact as an antagonistic receptor which protects cells from TRAIL-induced apoptosis.