Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.4.2.30 (PARP)
13,611 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

After weaning, the mammary gland ceases lactation and involutes. The wet weight of the gland decreases by 70% within 4 days of weaning. This involves significant tissue remodelling as the ducts regress and return to the resting state. The presence of apoptotic bodies in the luminal epithelial compartment 2 to 3 days after weaning provides clear evidence that a substantial proportion of the regression is attributable to the induction of active cell death (ACD) of the epithelial cells. These changes in the architecture of the gland were found to be mirrored by changes in gene expression. The steady-state level of beta-casein mRNA decreased rapidly after weaning from the high levels seen during lactation to undetectable levels by 8 days after weaning. The steady-state levels of expression of a number of genes associated with ACD, including TRPM-2, tissue transglutaminase (TGase) and poly(ADP-ribose) polymerase (PARP), increased transiently during this time-frame. The steady-state level of TRPM-2 mRNA increased 2 days after weaning, reaching a peak on day 4, and decreasing to undetectable levels by day 8 after weaning. The steady-state levels of two other mRNAs, TGase and PARP, showed very similar kinetics. In contrast, the mRNA for Hsp 27, which has been shown to be induced during prostate regression, was not significantly induced in the regressing mammary gland. In-situ hybridization demonstrated that the TRPM-2, TGase and PARP genes were expressed predominantly in the luminal epithelial cells of the ducts. These cells expressed beta-casein mRNA during lactation, and underwent ACD after weaning. While the ultrastructural changes in the mammary gland after weaning, and the induction of TRPM-2, TGase and PARP mRNAs, are reminiscent of apoptosis in the prostate, several features of the process are different. Most notably, the disruption of the secretory processes and the lack of increased expression of Hsp 27 in the regressing mammary gland suggest that there may be a number of important events in ACD that are not common to all cells.
J Mol Endocrinol 1994 Feb
PMID:Induction of gene expression during involution of the lactating mammary gland of the rat. 818 14

A series of Trypanosoma brucei transfection vectors was constructed in which transcription of the luciferase gene was driven by the procyclic acidic repetitive protein (procyclin) promoter. The untranslated regions surrounding the luciferase gene were derived from the actin, fructose bisphosphate aldolase, or PARP loci. Trans-splicing of the resulting transcripts occurred as expected, but the site of 3' polyadenylation was upstream of the position anticipated. The nature of the 3'-untranslated region was crucial to the level of expression in bloodstream forms.
Mol Biochem Parasitol 1993 Sep
PMID:A possible role for the 3'-untranslated region in developmental regulation in Trypanosoma brucei. 825 36

Five monoclonal antibodies (mAb) were raised that bound to the surface of procyclic stage Trypanosoma congolense with high intensity in immunofluorescence. Immunoblot analysis of trypanosome lysates using 3 of these mAb revealed a diffuse SDS-PAGE band of 36-40 kDa. The purified antigen did not react with Coomassie Blue or silver stains, but did stain blue with Stains-all, indicating acidity. For the one mAb tested, the epitope was periodate-sensitive and therefore probably glycan. Although this antigen shares properties with procyclin/PARP, which forms a surface coat on procyclic Trypanosoma brucei, a search in T. congolense for homologues of a procyclin/PARP gene revealed only non-coding sequence of partial similarity. Using a differential screen, a procyclic stage T. congolense cDNA clone was isolated that encoded a putative 256-amino acid protein containing 2 peptides chemically sequenced independently by Beecroft et al. [36]. The protein, termed glutamate and alanine-rich protein (GARP), has potential hydrophobic leader and tail sequences (the latter with potential for replacement by a glycosyl phosphoinositol anchor) and no potential N-linked glycosylation sites. It has no significant sequence homology with known proteins. Antibodies against a translational fusion of GARP bound specifically in Western blots to a band very similar to that detected by the mAb and also to the purified antigen. Immunogold electron microscopy revealed a dense packing of the antigen on the cell surface. It appears that procyclic T. brucei and T. congolense have major surface proteins with structural analogy, but with no sequence homology.
Mol Biochem Parasitol 1993 Oct
PMID:A major surface antigen of procyclic stage Trypanosoma congolense. 826 32

Evidence is accumulating that rho p21, a ras p21-related small GTP-binding protein (G protein), regulates the actomyosin system. The actomyosin system is known to be essential for cell motility. In the present study, we examined the action of rho p21, its inhibitory GDP/GTP exchange protein (named rho GDI), its stimulatory GDP/GTP exchange protein (named smg GDS), and Clostridium botulinum ADP-ribosyltransferase C3, known to selectively ADP-ribosylate rho p21 and to impair its function, in cell motility (chemokinesis) of Swiss 3T3 cells. We quantitated the capacity of cell motility by measuring cell tracks by phagokinesis. Microinjection of the GTP gamma S-bound active form of rhoA p21 or smg GDS into Swiss 3T3 cells did not affect cell motility, but microinjection of rho GDI into the cells did inhibit cell motility. This rho GDI action was prevented by comicroinjection of rho GDI with the GTP gamma S-bound form of rhoA p21 but not with the same form of rhoA p21 lacking the C-terminal three amino acids which was not posttranslationally modified with lipids. The rho GDI action was not prevented by Ki-rasVal-12 p21 or any of the GTP gamma S-bound form of other small GTP-binding proteins including rac1 p21, G25K, and smg p21B. Among these small G proteins, rhoA p21, rac1 p21, and G25K are known to be substrates for rho GDI. The rho GDI action was not prevented by comicroinjection of rho GDI with smg GDS. Microinjection of C3 into Swiss 3T3 cells also inhibited cell motility. These results indicate that the rho GDI-rho p21 system regulates cell motility, presumably through the actomyosin system.
Mol Cell Biol 1993 Jan
PMID:Involvement of rho p21 and its inhibitory GDP/GTP exchange protein (rho GDI) in cell motility. 841 62

In a previous report we described that adenosine-induced apoptosis of HL-60 cells was blocked by the pretreatment of cells with a potent inhibitor (3-aminobenzamide) of poly(ADP-ribose) polymerase (PARP). The pretreatment of the cells with nicotinamide, another inhibitor of the enzyme, also suppressed most effectively the adenosine-induced apoptosis. This inhibition was reversible and observed during apoptosis mediated by other known apoptosis inducers such as actinomycin D and staurosporine (group I inducers), but nicotinamide was ineffective on the apoptosis mediated by VM 26, camptothecin and A23187 (group II inhibitors). In addition to the enzyme inhibition, a down-regulation of the enzyme level caused by the pretreatments of cells with differentiation-inducing agents, retinoic acid (RA) and dimethylsulfoxide (DMSO) also resulted in a marked resistance of the cells to the apoptosis inducers. A pretreatment of the cells for a limited time of 24 hrs. by these agents decreased the PARP level to 66-75% of the untreated cells and the cells showed a quite similar resistance to the group I apoptosis inducers like the cells treated with the enzyme inhibitors, whereas they were still sensitive to the group II inhibitors. A more prolonged treatment for 48 hrs. of the cells with RA and DMSO resulted in further down-regulation of the cellular PARP reaching respectively 50 and 43% of control cells and at this stage, the cells became resistant to all the inducers of both groups. These results suggest that the pathway, by which both groups of the inducers initiate and progress apoptosis, is not identical but include at least two different processes which are differently affected by PARP-inhibition or by different levels of cellular PARP.
Cell Mol Biol (Noisy-le-grand) 1995 Sep
PMID:Inhibition and down-regulation of poly(ADP-ribose) polymerase results in a marked resistance of HL-60 cells to various apoptosis-inducers. 853 70

The polycistronic procylcin PARP (for procyclic acidic repetitive protein) A transcription unit of Trypanosoma brucei was completely characterized by the mapping of the termination region. In addition to the tandem of procyclin genes and GRESAG 2.1, this 7.5- to 9.5-kb unit contained another gene for a putative surface protein, termed PAG (for procyclin-associated gene) 3. The terminal 3-kb sequence did not contain significant open reading frames and cross-hybridized with the beginning of one or several transcription units specific to the bloodstream form. At least three separate fragments from the terminal region were able to inhibit chloramphenicol acetyltransferase expression when inserted between either the PARP, the ribosomal, or the variable surface glycoprotein promoter and a chloramphenicol acetyltransferase reporter gene. This inhibition was due to an orientation-dependent transcription termination caused by the combination of several attenuator elements with no obvious sequence conservation. The procyclin transcription terminator appeared unable to inhibit transcription by polymerase II.
Mol Cell Biol 1996 Mar
PMID:Characterization of a transcription terminator of the procyclin PARP A unit of Trypanosoma brucei. 862 94

ADP-ribosylation factors (ARFs) are approximately 20-kDa guanine nucleotide-binding proteins that are allosteric activators of the NAD:arginine ADP-ribosyltransferase activity of cholera toxin and appear to play a role in intracellular vesicular trafficking. Although the physiological roles of these proteins have not been defined, it has been presumed that each has a specific intracellular function. To obtain genetic evidence that each ARF is under evolutionary pressure to maintain its structure, and presumably function, rat ARF cDNA clones were isolated and their nucleotide and deduced amino acid sequences were compared to those of other mammalian ARFs. Deduced amino acid sequences for rat ARFs 1, 2, 3, 5 and 6 were identical to those of the known cognate human and bovine ARFs; rat ARF4 was 96% identical to human ARF4. Nucleotide sequences of both the untranslated as well as the coding regions were highly conserved. These results indicate that the ARF proteins are, as a family, extraordinarily well conserved across mammalian species. The unusually high degree of conservation of the untranslated regions is consistent with these regions having important regulatory roles and that individual ARFs contain structurally unique elements required for specific functions.
Mol Cell Biochem 1996 Jun 07
PMID:Interspecies relationships among ADP-ribosylation factors (ARFs): evidence of evolutionary pressure to maintain individual identities. 881 5

Poly(ADP-ribose) polymerase (PARP) is a nuclear enzyme which catalyzes the transfer of ADP-ribose units from NAD+ to a variety of nuclear proteins under the stimulation of DNA strand break. To examine its role in DNA repair, we have been studying the interaction of PARP with other nuclear proteins using disulfide cross-linking, initiated by sodium tetrathionate (NaTT). Chinese Hamster Ovary (CHO) cells were extracted sequentially with Nonidet P40 (detergent), nucleases (DNase+RNase), and high salt (1.6 M NaCl) with and without the addition of a sulfhydryl reducing agent. The residual structures are referred to as the nuclear matrix, and are implicated in the organization of DNA repair and replication. Treatment of the cells with NaTT causes the crosslinking of PARP to the nuclear matrix. Activating PARP by pretreating the cells with H2O2 did not increase the cross-linking of PARP with the nuclear matrix, suggesting a lack of additional interaction of the enzyme with the nuclear matrix during DNA repair. Both NaTT and H2O2 induced crosslinks of PARP that were extractable with high salt. To shorten the procedure, these crosslinks were extracted from cells without nucleases and high salt treatment, using phosphate buffer. Using western blotting, these crosslinks appeared as a smear of high molecular weight species including a possible dimer of PARP at 230 kDa, which return to 116 kDa following reduction with beta-mercaptoethanol.
Mol Cell Biochem 1996 Jun 21
PMID:Association of poly(ADP-ribose) polymerase with nuclear subfractions catalyzed with sodium tetrathionate and hydrogene peroxide crosslinks. 885 66

Hypo-osmotic stimulation of human Intestine 407 cells rapidly activated compensatory CL- and K+ conductances that limited excessive cell swelling and, finally, restored the original cell volume. Osmotic cell swelling was accompanied by a rapid and transient reorganization of the F-actin cytoskeleton, affecting both stress fibers as well as apical ruffles. In addition, an increase in total cellular F-actin was observed. Pretreatment of the cells with recombinant Clostridium botulinum C3 exoenzyme, but not with mutant enzyme (C3-E173Q) devoid of ADP-ribosyltransferase activity, greatly reduced the activation of the osmo-sensitive anion efflux, suggesting a role for the ras-related GTPase p21rho. In contrast, introducing dominant negative N17-p21rac into the cells did not affect the volume-sensitive efflux. Cell swelling-induced reorganization of F-actin coincided with a transient, C3 exoenzyme-sensitive tyrosine phosphorylation of p125 focal adhesion kinase (p125FAK) as well as with an increase in phosphatidylinositol-3-kinase (PtdIns-3-kinase) activity. Pretreatment of the cells with wortmannin, a specific inhibitor of PtdIns-3-kinase, largely inhibited the volume-sensitive ion efflux. Taken together, our results indicate the involvement of a p21rho signaling cascade and actin filaments in the activation of volume-sensitive chloride channels.
Mol Biol Cell 1996 Sep
PMID:Activation of the osmo-sensitive chloride conductance involves P21rho and is accompanied by a transient reorganization of the F-actin cytoskeleton. 888 36

ADP-ribosylation factors (ARFs) are approximately 20-kDa, guanine nucleotide-binding proteins, initially discovered as stimulators of cholera toxin ADP-ribosyltransferase activity and subsequently shown to participate in vesicular trafficking. Five of the six mammalian ARFs have been identified in human tissues by molecular cloning. They fall into three classes (class I: ARFs 1-3; class II: ARFs 4, 5; class III: ARF 6) based on deduced amino acid sequence, size, phylogenetic analysis, and gene structure. Similar to the rab family of approximately 20 kDa guanine nucleotide-binding proteins, the ARFs appear to function in specific trafficking pathways. The presence of a specific ARF might serve as a marker for that pathway. To verify expression of ARF mRNA and protein in human umbilical vein endothelial cells, immunoreactivity using antibodies specific for each ARF class, quantitative polymerase chain reaction (PCR) using ARF-specific, internal cRNA standards containing unique restriction enzyme cleavage sites introduced by point mutations, and Northern analysis with probes specific for ARFs 1, and 3-6, were utilized. PCR and Northern analysis were in agreement in showing that amounts of mRNA for ARF 1 and ARF 4 were similar and higher than those of ARF 3 and ARF 5 which were greater than ARF 6. Primarily, Class 1 ARF proteins were detected by immunoreactivity, with the majority in the supernatant fraction. The relative expression of ARFs in endothelial cells thus differs from that in neuronal tissues where it had been found that ARF3 is the predominant species.
J Mol Cell Cardiol 1996 Sep
PMID:Expression in human endothelial cells of ADP-ribosylation factors, 20-kDa guanine nucleotide-binding proteins involved in the initiation of vesicular transport. 889 50


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