Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of leukotriene C4, indomethacin, aspirin and prostaglandin E2 on macrophage activity were investigated, whereby the release of the lysosomal enzyme beta-glucuronidase was taken as a criterion for cell activity. Leukotriene C4 enhanced the release of beta-glucuronidase as well as the production of prostaglandin E2. Blocking the production of endogenous prostaglandins by adding indomethacin or aspirin resulted in an augmented effect of leukotriene C4. Exogenous prostaglandin E2 could reverse the leukotriene C4 and/or indomethacin induced beta-glucuronidase release. These results support the postulated interaction between leukotriene C4 and prostaglandin E2 with respect to the regulation of macrophage activity, leukotriene C4 being stimulatory, prostaglandin E2 suppressive.
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PMID:Cyclooxygenase inhibitors promote the leukotriene C4 induced release of beta-glucuronidase from rat peritoneal macrophages: prostaglandin E2 suppresses. 308 52

A Chlamydomonas reinhardtii chloroplast transformant, designated MU7, carrying a chimeric (rbcL promoter: beta-glucuronidase [GUS]: psaB 3' end) gene whose transcripts have been found previously to be unstable in light (half-life of 20 min in light as opposed to a half-life of 5 h in the dark), was used to study the role of electron transport and of the redox state in the degradation of chloroplast transcripts in the light. Blocking photosynthetic electron transport with 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) prevented the light-dependent breakdown of the pool of GUS transcripts in MU7 cells. Diamide, an oxidizing agent, caused a measurable delay in the degradation of GUS transcripts in the light. The addition of dithiothreitol (DTT), a dithiol reductant, to MU7 cells in which GUS transcript levels were stabilized by DCMU induced degradation of GUS transcripts. Similarly, DTT induced a decrease in the levels of GUS transcripts when added to MU7 cells in the dark period of the light/dark cycle, a period in which GUS transcript levels normally increase. The levels of transcripts of endogenous chloroplast genes were affected by DCMU and DTT in the same direction as levels of GUS transcripts. The results suggest a regulatory role of the redox state in the degradation of chloroplast transcripts in C. reinhardtii.
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PMID:The redox state regulates RNA degradation in the chloroplast of Chlamydomonas reinhardtii. 1059 24

The actin cytoskeleton has been implicated in regulating plant gravitropism. However, its precise role in this process remains uncertain. We have shown previously that disruption of the actin cytoskeleton with Latrunculin B (Lat B) strongly promoted gravitropism in maize roots. These effects were most evident on a clinostat as curvature that would exceed 90 degrees despite short periods of horizontal stimulation. To probe further the cellular mechanisms underlying these enhanced gravity responses, we extended our studies to roots of Arabidopsis. Similar to our observations in other plant species, Lat B enhanced the response of Arabidopsis roots to gravity. Lat B (100 nm) and a stimulation time of 5-10 min were sufficient to induce enhanced bending responses during clinorotation. Lat B (100 nm) disrupted the fine actin filament network in different regions of the root and altered the dynamics of amyloplasts in the columella but did not inhibit the gravity-induced alkalinization of the columella cytoplasm. However, the duration of the alkalinization response during continuous gravistimulation was extended in Lat B-treated roots. Indirect visualization of auxin redistribution using the DR5:beta-glucuronidase (DR5:GUS) auxin-responsive reporter showed that the enhanced curvature of Lat B-treated roots during clinorotation was accompanied by a persistent lateral auxin gradient. Blocking the gravity-induced alkalinization of the columella cytoplasm with caged protons reduced Lat B-induced curvature and the development of the lateral auxin gradient. Our data indicate that the actin cytoskeleton is unnecessary for the initial perception of gravity but likely acts to downregulate gravitropism by continuously resetting the gravitropic-signaling system.
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PMID:The promotion of gravitropism in Arabidopsis roots upon actin disruption is coupled with the extended alkalinization of the columella cytoplasm and a persistent lateral auxin gradient. 1520 Jun 46