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

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.
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PMID:A major surface antigen of procyclic stage Trypanosoma congolense. 826 32

The effect of environmental acidity on the induction of apoptosis by heat was investigated. Human colorectal tumour RKO.C cells, carrying wild-type p53 and isogenic RC10.1 cells deficient in p53, were heated at 42.0 degrees C for 1 h in pH 7.5 or pH 6.6 medium and the apoptosis was assessed based on the flow cytometic determination of DNA content, DNA fragmentation, and PARP cleavage. The degree of apoptosis after heating in pH6.6 medium was greater than that in pH 7.5 medium in both RKO.C cells and RC10.1 cells. When heated in the same pH medium, more apoptosis occurred in the RC10.1 cells than in the RKO.C cells. Heating increased the expression of p53 protein and p21 protein markedly in RKO.C cells and slightly in RC10.1 cells. Expression of these proteins was slightly greater in pH 7.5 medium than in pH 6.6 medium. The expressions of Bax protein and Bcl-2 protein, which are known to control apoptosis, were not altered by heating. It was concluded that an acidic environment enhances heat-induced apoptosis. It was also concluded that heat-induced apoptosis is lessened by p53 and that Bcl-2 and Bax are not involved in the induction of apoptosis by hyperthermia.
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PMID:Effect of acidic environment and p53 on apoptosis induction by hyperthermia. 1112 60

High expression of Cyr61, an extracellular cysteine-rich heparin-binding protein, has been associated with a malignant cell phenotype and poor outcome in prostate cancers. Although Cyr61 was found by us to be overproduced in androgen-independent PC-3 cells treated with N-acetylcysteine (NAC), its significance is still unclear. We therefore aimed to determine how and why Cyr61 protein is overexpressed in NAC-treated cells. Here, we found that Cyr61 protein level markedly increased in cells treated with NAC at high cell seeding density. Silencing of Cyr61 by siRNA induced enhanced activity of caspase-3/7, upregulation of the proapototic Bok, BimL and BimS, cleavage of apoptosis hallmarkers such as Bax, PARP and caspase-3, and downregulation of antiapoptotic Bcl2, Bcl-xL and Mcl-1 proteins. NAC treatment caused a reduction of extracellular medium pH to acidic and an increase in Akt phosphorylation, after which the replacement with NAC-free medium returned them to control levels within 24h. Acid stimulation increased the levels of Cyr61 and p-Akt proteins, whereas it suppressed the induction of proapoptotic and antiapoptotic proteins. Overall, our data indicate that PC-3 cells overproduce Cyr61 protein via activation of the PI3K/Akt signaling as a part of the survival mechanisms under the conditions causing extracellular acidity and further cytotoxicity.
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PMID:Production of Cyr61 protein is modulated by extracellular acidification and PI3K/Akt signaling in prostate carcinoma PC-3 cells. 2362 39

The Crassulacean acid metabolism (CAM) pathway helps plants to alleviate the oxidative stress under drought, but the shift to CAM-idling may expose plants to the overproduction of reactive oxygen species causing cell damages. The facultative CAM species Portulacaria afra L., was subjected to long-term water deprivation to assess the photo-protective strategies and the poly (ADP-ribose) polymerase (PARP) activity during water stress and plant capability to recover from the stress. Measurements of titratable acidity, chlorophyll fluorescence emission, and antioxidant activity were performed during the stress and rewatering. Under water deprivation, plants shifted from C3 to CAM metabolism, reaching the CAM-idling status at the end of the stress period. The daily variation of the titratable acidity and PARP activity increased at the beginning of stress and declined with stress progression, reaching the lowest value at the end of stress treatment. H2O2 content, superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities increased with the severity of water stress. The photochemical processes remained high during the entire stress period indicating the presence of alternative sinks to CO2 fixation. The elevated activity of catalase under severe water stress suggests the occurrence of photorespiration in sustaining the photosynthetic electron transport under CAM-idling condition. The overall data indicate that scavenger enzymes, photorespiration and PARP activity modulation contribute to the strong resistance of P. afra to severe water stress, preserving the functioning of photosynthetic apparatus and ensuring plant recovery with rewatering.
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PMID:Photo-Protective Mechanisms and the Role of Poly (ADP-Ribose) Polymerase Activity in a Facultative CAM Plant Exposed to Long-Term Water Deprivation. 3293 15