Search results

cAMP-regulated phosphoprotein 19 (ARPP19) is protein phosphatase inhibitor which specifically inhibits protein phosphatase 2A (PP2A) during mitosis. When phosphorylated at Ser-62 during mitosis, ARPP19 specifically interacts with PPP2R2D (PR55-delta) and inhibits its activity, leading to inactivation of PP2A, a vital condition to maintain cyclin-B1-CDK1 activity high during M phase. ARPP19 protein may indirectly boost GAP-43 expression. The 19 kDa cAMP-regulated phosphoprotein has a role in regulating mitosis by obstructing protein phosphatase-2A.

Sorting nexin 3 (SNX3) belongs to the large family of hydrophilic proteins, which interact with various receptor types and are involved in intracellular trafficking. SNX3 interacts with phosphatidylinositol-3-phosphate, and is involved in protein trafficking. SNX3 comprises a distinct subgroup of nexins, which share less sequence similarity outside of the PX domain and have significantly different binding affinities for the tyrosine kinase receptors.

The signal sequence receptor (SSR) is a glycosylated endoplasmic reticulum membrane receptor related with protein translocation across the ER membrane. The SSR consists of 2 subunits, a 34-kD glycoprotein (alpha-SSR or SSR1) and a 22-kD glycoprotein (beta-SSR or SSR2). The human beta-signal sequence receptor gene (SSR2) maps to chromosome bands 1q21-q23. Diseases correlated with SSR2 include calcaneonavicular coalition, and osteosarcoma, and among its related super-pathways are Viral mRNA Translation and Generic Transcription Pathway.

Translocase of Inner Mitochondrial Membrane 8 Homolog A (TIMM8A) takes part in the import and insertion of hydrophobic membrane proteins from the cytoplasm into the mitochondrial. TIMM8A plays a role as a chaperone-like protein which protects the hydrophobic precursors from aggregation and leads them through the mitochondrial intermembrane space. TIMM8A is essential for the transfer of beta-barrel precursors from the TOM complex to the sorting and assembly machinery (SAM complex) of the outer membrane. Defects in TIMM8A cause Jensen syndrome. TIMM8A and TIMM13, forms a 70 kDa heterohexamer.

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.

43 kDa receptor-associated protein of the synapse (RAPSN), is expressed in the postsynaptic membrane of skeletal muscle. RAPSN is essential for the clustering of nicotinic acetylcholine receptors (nAChR). In addition RAPSN self-associates via at least two of its seven tetra-tricopeptide repeats (TPRs). RAPSN interacts with the large intracellular domain of the nAChR a subunit all the way through the hydrophobic surface of the coiled-coil domain. RAPSN modifies trafficking of AChR within the cell. Overexpression inhibits agrin-induced AChR clustering pathway. RAPSN also plays a role in postsynaptic congenital myasthenic syndromes.

The 14-3-3 family of proteins plays a key regulatory role in signal transduction, checkpoint control, apoptotic and nutrient-sensing pathways. 14-3-3 proteins are highly conserved and ubiquitously expressed. There are at least seven isoforms that have been identified in mammals. The 14-3-3gamma, a subtype of the 14-3-3 family of proteins, was thought to be brain and neuron-specific. It has been shown to interact with RAF1 and protein kinase C, proteins involved in various signal transduction pathways.

Chromgranin-A is part of the neuroendocrine secretory protein family. CHGA is located in secretory vesicles of neurons and endocrine cells. Chromgranin-A is a precursor to three biologically active peptides; vasostatin, pancreastatin, and parastatin. These peptides act as autocrine or paracrine negative modulators of the neuroendocrine system. Other peptides, including chromostatin, beta-granin, WE-14 and GE-25, are also derived from the full-length protein. Chromgranin-A has numerous biological activities on some tissues and organs and exerts a large spectrum of homeostatic actions, including antifungal and antimicrobial effect, modulation of cell adhesion, and inhibition of parathyroid hormone secretion.

SAP18 is a component of the histone deacetylase complex which has a significant role in the regulation of eukaryotic gene expression. SAP18 directly interacts with SIN3 and enhances SIN3-mediated transcriptional repression once bound to the promoter. SAP18 plays an important part in gene-specific recruitment of the HDAC complex by a number of transcription factors including Gli, GAGA, and Bicoid. Histone acetylation is significant in the regulation of eukaryotic gene expression. Histone acetylation and deacetylation is catalyzed by multisubunit complexes. SAP18 is a component of the histone deacetylase complex, which includes SIN3, SAP30, HDAC1, HDAC2, RbAp46, RbAp48, and other polypeptides. SAP18 is a component of a splicing-dependent multiprotein EJC (exon junction complex) placed at splice junction on mRNAs.

Myozenin 1 (MYOZ1) is a member of the myozenin family. MYOZ1 is mostly expressed in the skeletal muscle. Members of the myozenin family act as calcineurin-interacting proteins which helps tether calcineurin to the sarcomere of cardiac and skeletal muscle. The myozenin family plays a significant role in modulation of calcineurin signaling.

Celiac disease is an enteropathy that is characterized by intestinal lesions of variable severity. Tissue-type transglutaminase (tTG) is believed to be the predominant autoantigen for celiac disease and the corresponding autoantibodies show higher sensitivity and specificity than anti-gliadin antibodies. Highly pure recombinant human tTG is now available to replace the traditionally used tTG fraction from guinea pig.
Tissue-type transglutaminase antigens have been specifically modified for improved handling: exchange of an active site amino acid eliminates the protein cross-linking activity of the enzyme, while maintaining the native three-dimensional structure and the enzyme's secondary GTPase activity. This engineering assures reproducible properties of the antigen preparations through the absence of variable and ill-defined covalent aggregates of tTG antigen and host cell proteins.

STX12 is a member of the syntaxin family which are cellular receptors for transport of vesicles that take part in exocytosis in neutrophils. STX12 regulates protein transport from late endosomes and the trans-Golgi network and back. Additionally, STX12 cooperates with ABC1 (ATP-binding cassette transporter A1), which enables cellular release of cholesterol and choline-phospholipids to apoA-I (apolipoprotein A-I).

SQSTM1 is an adapter protein which binds ubiquitin and mediates the activation of NFKB1 by TNF-a, NGF and IL-1. SQSTM1 is involved in titin/TTN downstream signaling in muscle cells. SQSTM1 controls signaling cascades through ubiquitination. SQSTM1 participates in cell differentiation, apoptosis, immune response and regulation of K(+) channels. Mutations in UBA domain of the SQSTM1 protein cause Paget’s disease because the UBA is essential for aggregate sequestration and cell survival.

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.

Signal-Regulatory Protein Alpha, SIRPA belongs to the signal-regulatory-protein (SIRP) family, as well as theimmunoglobulin super family. The members of the SIRP family are receptor-type transmembrane glycoproteins which areinvolved in the negative regulation of receptor tyrosine kinase-coupled signaling processes. SIRPA can bephosphorylated by tyrosine kinases. The phospho-tyrosine residues of this PTP have been shown to recruit SH2domain containing tyrosine phosphatases (PTP), and perform as substrates of PTPs. SIRPA take part insignal transduction mediated by a variety of growth factor receptors. CD47 has been shown to be a ligand for SIRPA.

Pleiotrophin (Osteoblast-Specific Factor-1, OSF-1) contains 136 amino acid residues. The sequence is very rich in cationic amino acids (24% of the residues); lysine cluster sequences are found in the N-terminal and C-terminal ends of the structure.
The OSF-1 gene was shown by Northern blotting analysis to be expressed in mouse calvarial osteoblast-enriched cells and in mouse brain tissues, but not in thymus, spleen, kidney, liver, lung, testis or heart. Pleiotrophin has the ability to promote adhesion, migration, expansion, and differentiation of human osteoprogenitor cells. In addition to certain types of cancer, the embryonic growth and differentiation factor pleiotrophin is found also in adults in inflammatory diseases. In osteoarthritis, pleiotrophin is especially expressed in early stages, and its concentrations in the synovial fluid could serve as a marker for the progress of the disease. Pleitrophin might be involved in cartilage repair in osteoarthritis, in particular, in earlier stages.

NAP1L1 is a member of the nucleosome assembly protein (NAP) family. NAP1L1 protein plays a part in DNA replication, modulating chromatin formation and regulation of cell proliferation.

XCL1 is a small cytokine belongs to the XC chemokine family that is also known as lymphotactin. XCL1 is found in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

Transferrin is the iron-transport protein of vertebrate serum and donates iron to cells through interaction with a specific membrane receptor, CD71. Transferrin appears to be indispensable for most cells growing in tissue culture.
It is referred to frequently as a growth factor because, in analogy to other growth factor-receptor interactions, proliferating cells express high numbers of transferrin receptors, and the binding of transferrin to their receptors is needed for cells to initiate and maintain their DNA synthesis. Apart from its role as an iron transport protein transferrin acts as a cytokine and has functions that may not be related to its iron-carrying capacity.
Human Transferrin is a crucial component for the cultivation of mammalian cells in-vitro. Human Transferrin is Critical for long-term cells growth in-vitro. Human Transferrin is used as detoxificant in media by binding contaminating metal ions. Human Transferrin is often used as a nutrient in fermentation media for recombinant protein and biopharmaceutical production. Additional common uses of Human Transferrin areMolecular weight, Affinity purification of anti-human transferrin antibodies and also as receptor mediated transfection of molecules such as DNA, into cells.

SELPLG glycoprotein functions as a high affinity counter-receptor for the cell adhesion selectin molecules (P, E and L) located in stimulated T lymphocytes and myeloid cells. SELPLG binds leukocytes to activated platelets or endothelia expressing selectins, a vital role in leukocyte trafficking throughout inflammation. In order to have a high-affinity binding activity SELPLG needs two post-translational modifications, tyrosine sulfation and the addition of the sialyl Lewis x tetrasaccharide (sLex) to its O-linked glycans. Polymorphisms and abnormal expression of SELPLG are linked to defects in the innate and adaptive immune response. Alternate splicing results in multiple transcript variants.

Synovial Sarcoma, X Breakpoint 1 (SSX1) is a member of a family of highly homologous synovial sarcoma X (SSX) breakpoint proteins. SSX proteins are localized to the nucleus and expressed in testis and some types of cancers and, hence, they are classified as C/T (cancer/testis) antigens. These proteins may serve as transcriptional repressors. SSX1 genes are involved in the t (X;18) translocation typically found in all synovial sarcomas. This translocation leads to the fusion of the synovial sarcoma translocation gene on chromosome 18 to one of the SSX genes on chromosome X. These hybrid proteins are most likely responsible for transforming activity.

Signal-Regulatory Protein Alpha, SIRPA belongs to the signal-regulatory-protein (SIRP) family, as well as theimmunoglobulin super family. The members of the SIRP family are receptor-type transmembrane glycoproteins which areinvolved in the negative regulation of receptor tyrosine kinase-coupled signaling processes. SIRPA can bephosphorylated by tyrosine kinases. The phospho-tyrosine residues of this PTP have been shown to recruit SH2domain containing tyrosine phosphatases (PTP), and perform as substrates of PTPs. SIRPA take part insignal transduction mediated by a variety of growth factor receptors. CD47 has been shown to be a ligand forSIRPA.

Serine peptidase inhibitor Kazal type 7 (SPINK7) which includes one Kazal-like domain is most likely serine protease inhibitor. Diseases linked with SPINK7 include esophageal cancer, and oral squamous cell carcinoma

FABP1 (Fatty acid binding protein1) encodes the fatty acid binding protein found in liver. FABP1 is composed of ten antiparallel beta strands that form a barrel with a bigger binding pocket than the other FABPs allowing it to accommodate two fatty acid. This protein binds free fatty acids and their coenzyme A derivatives, bilirubin, and some other small molecules in the cytoplasm; it may be involved in intracellular lipid transport and metabolism.