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Mammalian mitochondrial ribosomal proteins are encoded by nuclear genes and assist in protein synthesis within the mitochondrion. Mitochondrial ribosomes (mitoribosomes) consist of a small 28S subunit and a large 39S subunit (MRPL13 is a 39S subunit protein) and have an estimated 75% protein to rRNA composition compared to prokaryotic ribosomes, where this ratio is reversed. An additional difference between mammalian mitoribosomes and prokaryotic ribosomes is that the second contain a 5S rRNA. Among various species, the proteins comprising the mitoribosome differ greatly in sequence, and sometimes in biochemical properties, which prevents easy recognition by sequence homology.

The bone morphogenetic proteins (BMPs) are a family of secreted signaling molecules that can induce ectopic bone growth. Many BMPs are part of the transforming growth factor-beta (TGFB) superfamily. BMPs were originally identified by an ability of demineralized bone extract to induce endochondral osteogenesis in vivo in an extraskeletal site. Based on its expression early in embryogenesis, the BMP encoded by this gene has a proposed role in early development. In addition, the fact that this BMP is closely related to BMP5 and BMP7 has lead to speculation of possible bone inductive activity.

The MutS DNA Mismatch Protein Identifies heteroduplex DNAs comprising mis-paired or unpaired bases. The MutS DNA Mismatch Protein binds in vitro to heteroduplex DNAs comprising mis-paired or unpaired bases over a varied temperature range from 4-70 °C and obtains a thermostable ATPase activity. The MutS DNA Mismatch Protein is active at temperature between 0 to 75°C. Since The MutS DNA Mismatch Protein competently binds to 1-4 bases deletion (or insertion) and mismatch base pairs of GT, CT and AG, it is suitable for sensing these mutations. Mutations can be distinguished in polyacrylamide gels or on a solid phase such as Ni agarose or beads or magnetic Ni-NTA particles.

MECP2 is the key modificator of eukaryotic genomes and has a crucial part in mammalian development.
Human proteins MECP2, MBD1, MBD2, MBD3, and MBD4 form a family of nuclear proteins linked by the existence in each of a methyl-CpG binding domain (MBD). Each one of these proteins, with the exception of MBD3, can bind specifically to methylated DNA. In addition, MECP2, MBD1 and MBD2 can inhibit transcription from methylated gene promoters. Unlike other MBD family members, MECP2 is X-linked and subject to X inactivation. MECP2 is expendable in stem cells, but is vital for embryonic development. MECP2 gene mutations are the cause of most cases of Rett syndrome, a progressive neurologic developmental disorder and one of the most common reasons of mental retardation in females.

FSCN1 is an actin-bundling protein that is responsible for rigidity to filopodial bundles to efficiently push the membrane forward during cytoskeleton remodeling and cell migration. FSCN1 takes part in the gathering of actin filament bundles present in microspikes, membrane ruffles, and stress fibers. FSCN1 is absent from most normal epithelia though is upregulated in multiple forms of human carcinoma, where its expression associates clinically with a poor prognosis. FSCN1 expression is abundantly found in neurons, glial cells, and endothelial cells.

PRKAB2 is a regulatory subunit of the AMP-activated protein kinase (AMPK). AMPK is a heterotrimer contains an alpha catalytic subunit and non-catalytic beta and gamma subunits. AMPK is a significant energy-sensing enzyme that supervises cellular energy status. AMPK is activated as a reply to cellular metabolic stresses, therefore phosphorylates and inactivates acetyl-CoA carboxylase (ACC) and beta-hydroxy beta-methylglutaryl-CoA reductase (HMGCR), vital enzymes involved in regulating de novo biosynthesis of fatty acid and cholesterol. PRKAB2 is a positive regulator of AMPK activity and highly expressed in skeletal muscle.

C4BP has a flower shaped structure with each alpha chain radiating out from a central core. The arms are linked by disulfide bonds in the centre and the ends of each arm bind C4b. C4BP acts as a cofactor allowing factor I to split and permanently inactivate C4b. C4b binding protein modulates complement activation of the classical and lectin pathways. C4BP binds to C4b and accelerates the dissociation of C2a from the C3/C5 convertase C4b,C2a. This inactivates the central enzyme of both pathways. Studies have shown that on surfaces densely coated with C4b, C4BP can bind up to four C4b molecules simultaneously.

TNNT2 is the tropomyosin-binding subunit of the troponin complex, which is situated on the thin filament of striated muscles and regulates muscle contraction in response to alterations in intracellular calcium ion concentration. Mutations in TNNT2 gene are related with familial hypertrophic cardiomyopathy as well as with dilated cardiomyopathy. TNNT2 mutation takes part in hypertrophic cardiomyopathy.

EPGN is an EGF-related polypeptide growth factor that signals through the ErbB receptor-1. EPGN is produced in numerous tissues, including the testis, liver, heart and in certain tumor cells. EPGN is mitogenic for fibroblasts and epithelial cells. Human EPGN is originally synthesized as a glycosylated 14.7 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a mature soluble sequence.

ETF is a heterodimer composed of alpha and beta subunit. ETFB protein is electron-transfer-flavoprotein, beta polypeptide that transports electrons between primary flavoprotein dehydrogenases involved in mitochondrial fatty acid and amino acid catabolism and the membrane-bound electron transfer flavoprotein ubiquinone oxidoreductase.

MAPRE2 (RP1 or EB2) is an evolutionarily conserved protein, which associates with the tips of growing microtubules, and regulates microtubule dynamics and their interactions with intracellular structures. The EB proteins regulate microtubule function through CLIP proteins. MAPRE2 shares noteworthy homology to the adenomatous polyposis coli (APC) protein-binding EB1 gene family. MAPRE2 is necessary for spindle symmetry during mitosis. MAPRE2 is believed to have a role in the tumorigenesis of colorectal cancers and the proliferative control of normal cells.

The cytokine Macrophage migration inhibitory factor (MIF) has been identified to be secreted by the pituitary gland and the monocyte/macrophage and to play an important role in endotoxic shock. MIF has the unique property of being released from macrophages and T cells in response to physiological concentrations of glucocorticoids. The secretion of MIF is tightly regulated and decreases at high, anti-inflammatory steroid concentration.

IGF-1 (Insulin-like growth factor-1) is a major hormonal mediator of statural growth. Under regular circumstances, GH (growth hormone) binds to its receptor in the liver, and other tissues, and stimulates the synthesis/secretion of IGF-1. In target tissues, the Type 1 IGF receptor, that is homologous to the insulin receptor, is activated by IGF-1, leading to intracellular signaling which stimulates multiple processes leading to statural growth. IGF-1 metabolic actions are partly directed at stimulating the uptake of glucose, fatty acids, and amino acids so that metabolism supports growing tissues.

DNA repair protein complementing XP-A cells, (XPA), is a member of the XPA family. XPA protein takes a part in DNA excision repair. It Inductees repair by binding to damaged sites with different affinities depending on the photoproduct and the transcriptional state of the region. Defects in XPA is the reason of xeroderma pigmentosum complementation group A (XP-A), which is infrequent human autosomal recessive disease which characterized by solar sensitivity, high predisposition for developing cancers on areas exposed to sunlight, also may cause to neurological abnormalities.

CTBP1 participates in controlling the equilibrium between tubular and stacked structures in the Golgi complex. CTBP1 functions in brown adipose tissue differentiation. CTBP1 has dehydrogenase activity. CTBP1 binds to the C-terminus of adenovirus E1A proteins. CTBP1 phosphoprotein is a transcriptional repressor and that takes part during cellular proliferation. CTBP1 & CTBP2 can dimerize and interact with a polycomb group protein complex which is involved in regulation of gene expression during development.

Members of the IFN regulatory factor (IRF) family regulate gene expression critical to immune response, hemopoiesis, and proliferation. IRF-3 is a member of the IRF family, and is distinct from other family members. Its transcriptional activity is regulated solely by posttranslational modifications. It plays a crucial role in activation of innate immunity and inflammation in response to viral infection. IRF-3 mediates IFN-stimulated response element (isre) promoter activation. Functions as a molecular switch for antiviral activity. Dsrna generated during the course of an viral infection leads to IRF3 phosphorylation on the c-terminal serine/threonine cluster. This induces a conformational change, leading to its dimerization, nuclear localization and association with creb binding protein (crebbp) to form dsrna-activated factor 1 (draf1), a complex which activates the transcription of genes under the control of isre. The complex binds to the ie and prdiii regions on the ifn-alpha and ifn-beta promoters respectively. IRF-3 does not have any transcription activation domains.

Recombinant Human Sonic Hedgehog is part of a small group of secreted proteins that are vital for development in both vertebrates and invertebrates. 3 mammalian hedgehog genes (sonic, desert, Indian) share about 60% homology. The Human Sonic Hedgehog is 99% homologous to the mouse gene. Sonic HedgeHog is a protein that is vital in guding the early embryo. It has been associated as the major inductive signal in patterning of the ventral neural tube, the anterior-posterior limb axis, and the ventral somites. Sonic HedgeHog binds to the patched receptor, which functions in association with smoothened, to activate the transcription of target genes. In the absence of sonic HedgeHog, patched receptor represses the constitutive signaling activity of smoothened. Sonic HedgeHog also regulates another factor, the gli oncogene. Sonic HedgeHog intercellular signal is essential for a various patterning events during development: signal produced by the notochord that induces ventral cell fate in the neural tube and somites, and the polarizing signal for patterning of the anterior-posterior axis of the developing limb bud. Sonic HedgeHog exhibits both floor plate- and motor neuron-inducing activity. Mutations in a long-range Sonic HedgeHog enhancer located in an intron of the limb region 1 gene result in preaxial polydactyly.

Otubain 1 (OTUB1) belongs to the ovarian tumor (OUT) superfamily of predicted cysteine proteases and inhibits cytokine gene transcription in the immune system through its interaction with a ubiquitin protease and E3 ubiquitin ligase. OTUB1 is a highly specific ubiquitin iso-peptidase, it cleaves ubiquitin from branched poly-ubiquitin chains but not from ubiquitinated substrates. OTUB1 is believed to work in specific ubiquitin-dependent pathways, possibly by providing an editing function of polyubiquitin chain growth. OTUB1 is a hydrolase that removes conjugated ubiquitin from proteins in vitro and may therefore have a significant regulatory role in the level of protein turnover by preventing degradation. Additionally, OTUB1 is a regulator of T-cell anergy, a phenomenon that occurs when T-cells are rendered impassive to antigen re-challenge and no longer respond to their cognate antigen. OTUB1 acts via its interaction with RNF128/GRAIL, which is an essential inductor of CD4 T-cell anergy.

Syndecan 2 (SDC2) is a conserved family of heparan- and chondroitin-sulfate carrying transmembrane protein. Syndecan 2 is a cell membrane proteoglycan which modulates the activity and dynamics of some growth factor receptors and integrins. SDC2 is expressed in HSCs (hepatic stellate cells), a key cell type involved in matrix deposition in liver fibrotic disorders. SDC2 is implicated in the formation of specialized membrane domains and serves as a direct link between the extracellular environment and the organization of the cortical cytoplasm.

RHOQ (rho-related GTP-binding protein RhoQ) is a small signaling G protein which cycles between an active GTP-bound and an inactive GDP-bound state. In the active state it binds to a diversity of effector proteins to regulate cellular responses. Ras-like protein belongs to the Rac subfamily of the Rho family of GTPases. RHOQ is involved in epithelial cell polarization processes. In addition, RHOQ plays a role in CFTR trafficking to the plasma membrane. RHOQ causes the formation of thin, actin-rich surface projections called filopodia.

KRT20 is a member of the keratin family. The keratins are intermediate filament proteins responsible for the structural integrity of epithelial cells and are subdivided into cytokeratins and hair keratins. The type I cytokeratins consist of acidic proteins which are arranged in pairs of heterotypic keratin chains. This cytokeratin is a major cellular protein of mature enterocytes and goblet cells and is specifically expressed in the gastric and intestinal mucosa. The type I cytokeratin genes are clustered in a region of chromosome 17q12-q21.

STAR facilitates the fast increase in pregnenolone synthesis stimulated by tropic hormones. STAR increases pregnenolone synthesis more than four-fold and a major STAR transcription of 1.6 kb is observed in ovary and testis. Throughout the growth and differentiation period of the ovary follicle, the immunoreactivity is likely to move from the granulosa cells of early antral follicles to the theca cell layers in the adult.

PDGFRa is a cell surface tyrosine kinase receptor for PDGF family members. PDGFRa binds to both A and B subunits of PDGF. It is known that PDGFRa is vital for kidney development since mice heterozygous for the receptor display defective kidney phenotypes.

C3d is derived from human C3 after a series of proteolytic cleavages.C3d is prepared from purified human C3. The C3 is converted to C3b by treatment with the natural human C3 convertase and this C3b is converted to iC3b. Finally, this iC3b is cleaved with trypsin to yield C3d.If the C3b precursor was attached to a surface (as occurs during complement activation) the iC3b, C3dg and C3d fragments would remain covalently attached to that surface.C3d is able to attach to a surfaceonly during complement activation on a surface. Surface-bound C3d is linked to the target through an ester or an amide covalent bond. Ester bonds are unstable, thusC3d releasesfrom the particle.