Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q9NRP7 (fused)
 58,367 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acetyl coenzyme A (CoA) synthetase (ADP forming) (ACD) represents a novel enzyme of acetate formation and energy conservation (acetyl-CoA + ADP + P(i) right harpoon over left harpoon acetate + ATP + CoA) in Archaea and eukaryotic protists. The only characterized ACD in archaea, two isoenzymes from the hyperthermophile Pyrococcus furiosus, constitute 145-kDa heterotetramers (alpha(2), beta(2)). The coding genes for the alpha and beta subunits are located at different sites in the P. furiosus chromosome. Based on significant sequence similarity of the P. furiosus genes, five open reading frames (ORFs) encoding putative ACD were identified in the genome of the hyperthermophilic sulfate-reducing archaeon Archaeoglobus fulgidus and one ORF was identified in the hyperthermophilic methanogen Methanococcus jannaschii. The ORFs constitute fusions of the homologous P. furiosus genes encoding the alpha and beta subunits. Two ORFs, AF1211 and AF1938, of A. fulgidus and ORF MJ0590 of M. jannaschii were cloned and functionally overexpressed in Escherichia coli. The purified recombinant proteins were characterized as distinctive isoenzymes of ACD with different substrate specificities. In contrast to the Pyrococcus ACD, the ACDs of Archaeoglobus and Methanococcus constitute homodimers of about 140 kDa composed of two identical 70-kDa subunits, which represent fusions of the homologous P. furiosus alpha and beta subunits in an alphabeta (AF1211 and MJ0590) or betaalpha (AF1938) orientation. The data indicate that A. fulgidus and M. jannaschii contains a novel type of ADP-forming acetyl-CoA synthetase in Archaea, in which the subunit polypeptides and their coding genes are fused.
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PMID:Novel type of ADP-forming acetyl coenzyme A synthetase in hyperthermophilic archaea: heterologous expression and characterization of isoenzymes from the sulfate reducer Archaeoglobus fulgidus and the methanogen Methanococcus jannaschii. 1179 Jul 32

Ethylene biosynthesis in higher plants is regulated developmentally and environmentally. To investigate the regulation of ACC synthase gene expression, the promoters of Arabidopsis ACS genes, AtACS4, AtACS5, and AtACS7, were fused to a GUS reporter gene, and the recombinant transgenes were introduced into Arabidopsis to produce three groups of AtACS::GUS transgenic plants. Histochemic and fluorometric study of these transgenic plants revealed that promoters of AtACS4, AtACS, and AtACS7 are all active in dark-germinated seedlings. AtACS5 has the highest promoter activity in leaves of 2-week-old light-grown seedlings among the three AtACS genes studied. In the mature leaves, AtACS4 and AtACS7 genes are expressed in both veins and areoles, whereas AtACS5 is expressed at a higher level in the areoles and epidermal cells surrounding trichomes. The promoter activities of all these AtACS genes are found in the reproductive organs. AtACS5 and AtACS7 are highly expressed in petals, sepals, carpels, stamens, cauline leaves, inflorescence stems, and siliques, while AtACS4 expression is undetectable in the petals of open flowers. All three AtACS genes are expressed in root tissue. In the 2-week-old light-grown Arabidopsis, the AtACS4 promoter is responsive to the plant hormones IAA, ethylene, and ABA, and to darkness and wounding; the AtACS5 promoter to IAA, ABA, salt, high temperature, and wounding; and the AtACS7 promoter to GA3, ethylene, and ABA, and to darkness and salt. Low-temperature treatment abolishes the darkness-induced AtACS7 gene expression, but not that of AtACS4. Each AtACS gene has a unique expression profile during growth and development. It appears that at any developmental stage or any growth period of Arabidopsis, there is always a member of AtACS multigene family that is actively expressed.
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PMID:The GUS reporter-aided analysis of the promoter activities of Arabidopsis ACC synthase genes AtACS4, AtACS5, and AtACS7 induced by hormones and stresses. 1569 63

Dd-STATa, a Dictyostelium homolog of the metazoan STAT (signal transducers and activators of transcription) proteins, is necessary in the slug for correct entry into culmination. Dd-STATa-null mutant fails to culminate and its phenotype correlates with the loss of a funnel-shaped core region, the pstAB core region, which expresses both the ecmA and ecmB genes. To understand how the differentiation of pstAB core cells is regulated, we identified an EST that is expressed in the core cells of normal slugs but down-regulated in the Dd-STATa-null mutant. This EST, SSK348, encodes a close homolog of the Dictyostelium acetyl-CoA synthetase (ACS). A promoter fragment of the cognate gene, aslA (acetyl-CoA synthetase-like A), was fused to a lacZ reporter and the expression pattern determined. As expected from the behavior of the endogenous aslA gene, the aslA::lacZ fusion gene is not expressed in Dd-STATa-null slugs. In parental cells, the aslA promoter is first activated in the funnel-shaped core cells located at the slug anterior, the "pstAB core." During culmination, the pstAB core cells move down, through the prespore cells, to form the inner part of the basal disc. As the spore mass climbs the stalk, the aslA gene comes to be expressed in cells of the upper and lower cups, structures that cradle the spore head. Deletion and point mutation analyses of the promoter identified an AT-rich sequence that is necessary for expression in the pstAB core. This acts in combination with repressor regions that prevent ectopic aslA expression in the pre-stalk regions of slugs and the stalks of culminants. Thus, this study confirms that Dd-STATa is necessary for the differentiation of pstAB core cells, by showing that it is needed for the activation of the aslA gene. It also identifies aslA promoter elements that are likely to be regulated, directly or indirectly, by Dd-STATa.
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PMID:Evidence that the Dictyostelium STAT protein Dd-STATa plays a role in the differentiation of inner basal disc cells and identification of a promoter element essential for expression in these cells. 1573 68

The Arabidopsis ETO1 protein is a negative regulator of ethylene biosynthesis. It specifically inhibits the enzyme activity of type 2 1-aminocyclopropane-1-carboxylate synthases (ACC synthases or ACS) and promotes their degradation by a proteasome-dependent pathway. To further understand the function of the ETO1 family in the plant kingdom, we cloned a cDNA of LeEOL1 (Lycopersicon esculentum ETO 1- LIKE 1), an ETO1 homolog from tomato. LeEOL1 encodes a putative protein with domain architecture conserved in the Arabidopsis ETO1/EOL1/EOL2 proteins and in the predicted rice EOL proteins. LeEOL1 is expressed in leaf, stem, root, flower, and the full ripe stage of fruit, suggesting diverse regulatory roles in the development of tomato. Yeast two-hybrid analysis revealed specific interactions between LeEOL1 and type 2 ACC synthases. When the C-terminal 14 amino acids (TOE; target of ETO1) of LE-ACS3 specific to type 2 ACC synthases were fused to a type 1 ACS, LE-ACS2, at the corresponding position, it allowed LE-ACS2 to strongly interact with LeEOL1. A GFP-TOE(LE-ACS3) fusion protein expressed in rice calli and in the roots of wild-type Arabidopsis showed reduced stability compared to native GFP. However, the fluorescence of GFP-TOE(LE-ACS3) was comparable to that of the native GFP in Arabidopsis eto1-4 mutant. Furthermore, MG132 treatment significantly enhanced the fluorescence of GFP-TOE(LE-ACS3) in the roots of wild-type Arabidopsis. These results suggest that the ETO1-family-mediated ACS protein degradation pathway is conserved in both monocots and dicots, and that TOE acts as a protein destabilization signal recognized by the ETO1 protein family.
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PMID:The ACC synthase TOE sequence is required for interaction with ETO1 family proteins and destabilization of target proteins. 1689 71

Protein-based fluorescent and functional probes are widely used for real-time visualization, purification, and regulation of a variety of biological molecules. The protein-based probes can generally be targeted into subcellular compartments of eukaryotic cells by a particular short peptide sequence. Little is known, however, about the sequence that targets probes into the mitochondrial intermembrane space (IMS). To identify the IMS-targeting sequence, we developed a simple genetic screening method to discriminate the proteins localized in the IMS from those in the mitochondrial matrix, thereby revealing the minimum requisite sequence for the IMS targeting. An IMS-localized protein, Smac/DIABLO, was randomly mutated, and the mitochondrial localization of each mutant was analyzed. We found that the four residues of Ala-Val-Pro-Ile are required for IMS localization, and a sequence of these four residues fused with matrix-targeting signals is sufficient for targeting the Smac/DIABLO into the IMS. The sequence was shown to readily direct three dissimilar proteins of interest to the IMS, which will open avenues to elucidating the functions of the IMS in live cells.
ACS Chem Biol 2007 Mar 20
PMID:A minimal peptide sequence that targets fluorescent and functional proteins into the mitochondrial intermembrane space. 1745 95

Short peptide tags S6 and A1, each 12 residues in length, were identified from a phage-displayed peptide library as efficient substrates for site-specific protein labeling catalyzed by Sfp and AcpS phosphopantetheinyl transferases (PPTases), respectively. S6 and A1 tags were selected for useful levels of orthogonality in reactivities with the PPTases: the catalytic efficiency, kcat/Km of Sfp-catalyzed S6 serine phosphopantetheinylation was 442-fold greater than that for AcpS. Conversely, the kcat/Km of AcpS-catalyzed A1 labeling was 30-fold higher than that for Sfp-catalyzed A1 labeling. S6 and A1 peptide tags can be fused to N- or C-termini of proteins for orthogonal labeling of target proteins in cell lysates or on live cell surfaces. The development of the orthogonal S6 and A1 tags represents a significant enhancement of PPTase-catalyzed protein labeling, allowing tandem or iterative covalent attachment of small molecules of diverse structures to the target proteins with high efficiency and specificity.
ACS Chem Biol 2007 May 22
PMID:Genetically encoded short peptide tags for orthogonal protein labeling by Sfp and AcpS phosphopantetheinyl transferases. 1746 18

Androgen receptor (AR) induces cell proliferation by increasing the kinase activity of Src. We describe an approach for discriminating agonist and antagonist in a nongenomic steroid-signaling pathway using an association of AR with Src. We constructed a pair of genetically encoded indicators, where N- and C-terminal fragments of split firefly luciferase (FLuc) were fused to AR and Src, respectively. The fusion proteins with AR and Src are localized in the cytoplasm and on the plasma membrane, respectively. Upon being activated with androgen, AR undergoes an intramolecular conformational change and binds with Src. The association causes the complementation of the split FLuc and recovery of FLuc activity. The resulting luminescence intensities were taken as a measure of the rapid hormonal activity of steroids in the nongenomic AR signaling. Ten minutes are required for the AR-Src association by 5alpha-dihydroxytestosterone (DHT), which was completely inhibited by an antagonist, cyproterone acetate. The activities of ligands in the nongenomic pathway of AR were compared with those in the genomic pathway obtained on the basis of the nuclear trafficking of AR in mammalian cells. The comparison revealed that DHT and testosterone activate both genomic and nongenomic pathways of AR. 17beta-Estradiol and progesterone were found to be specific activators only for the genomic signaling pathway of AR. On the other hand, procymidone exhibited a specific activity only for the nongenomic signaling pathway of AR. The present approach is the first example addressing the agonistic and antagonistic activities of ligands in a nongenomic pathway of AR.
ACS Chem Biol 2007 Jul 20
PMID:Nongenomic activity of ligands in the association of androgen receptor with SRC. 1760 21

We report a versatile biofunctional subwavelength photonic device platform for real-time detection of biological molecules. Our devices contain lipid bilayer membranes fused onto metal oxide nanowire waveguides stretched across polymeric flow channels. The lipid bilayers incorporating target receptors are submersed in the propagating evanescent field of the optical cavity. We show that the lipid bilayers in our devices are continuous, have very high mobile fraction, and are resistant to fouling. We also demonstrate that our platform allows rapid membrane exchange. Finally, we use this device to detect the hybridization of specific DNA target sequences in solution to complementary probe DNA strands anchored to the lipid bilayer. This evanescent wave sensing architecture holds great potential for portable, all-optical detection systems.
ACS Nano 2008 Feb
PMID:Biofunctional subwavelength optical waveguides for biodetection. 1920 25

While nanocrystalline diamond is quickly becoming one of the most widely studied nanomaterials, achieving a large fraction of diamond nanoparticles in a polymer coating has been an unresolved problem. In this work, polymer nano- and microfibers containing high loadings of 5 nm diamond particles (up to 80 wt % in polyacrylonitrile and 40% in polyamide 11) have been demonstrated using electrospun nanofibers as a delivery vehicle. The electrospun nanofibers with a high load of nanodiamond in the polymers were fused into thin transparent films, which had high mechanical properties; an improvement of 4 times for the Young's modulus and 2 times for the hardness was observed already at 20% nanodiamond in polyamide 11. These films can provide UV protection and scratch resistance to a variety of surfaces, especially in applications where a combination of mechanical, thermal, and dielectric properties is required.
ACS Nano 2009 Feb 24
PMID:Nanodiamond-polymer composite fibers and coatings. 1923 73

Chemical tags for live cell imaging are emerging as viable alternatives to the fluorescent proteins for labeling proteins with small molecule probes. Among reported chemical tags, trimethoprim (TMP)-tag stands out for having sufficient cell permeability and selectivity to allow imaging of intracellular proteins. TMP-tag provides a noncovalent label in which the protein of interest is fused to E. coli dihydrofolate reductase (DHFR) and then labeled with a cell-permeable TMP-probe heterodimer. To complement the utility of the noncovalent TMP-tag, we sought to render the TMP-tag covalent for applications such as single-molecule tracking and pulse-chase labeling that would benefit from a more permanent modification. On the basis of the long-standing use of proximity-induced reactivity for irreversible inhibitor design and its more recent application to in vitro chemical biology tools, we designed an eDHFR variant with a unique cysteine residue positioned to react with an acrylamide electrophile installed on the TMP-probe label. In vitro experiments show that the eDHFR:L28C nucleophile reacts rapidly and quantitatively with the TMP-acrylamide-probe. Most significantly, the balance in reactivity provided by the acrylamide electrophile allows intracellular proteins tagged with eDHFR:L28C to be labeled with a TMP-acrylamide-fluorescein heterotrimer in live cells with minimal background. Thus, the TMP electrophile described here can be used immediately as a covalent chemical tag in live cells. Moreover, proximity-induced reactivity is shown to be sufficiently selective for use in a living cell, suggesting a general approach for the development of orthogonal covalent chemical tags from existing noncovalent ligand-protein pairs.
ACS Chem Biol 2009 Jul 17
PMID:An in vivo covalent TMP-tag based on proximity-induced reactivity. 1949 49


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