Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
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Target Concepts:
Gene/Protein
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Query: EC:3.1.4.3 (
phospholipase C
)
18,461
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Further analysis of hybrid clones from an experimental cross of Trypanosoma brucei rhodesiense 058 and T. b. brucei 196 shows 2 of the hybrid clones to have DNA contents about 1.5 times parental values. This represents over 40,000 kb of extra DNA. Comparison of the molecular karyotypes of parental and progeny trypanosomes shows that the bulk of the extra DNA constitutes chromosomes greater than 1 Mb in size, although a small proportion can be accounted for by an increased number of mini-chromosomes. The 2 hybrid clones have 3 alleles at several loci for
housekeeping
genes as shown by RFLP and isoenzyme analysis. Trisomy of the chromosome carrying phosphoglycerate kinase and tubulin genes and that carrying the
phospholipase C
gene was demonstrated by analysis of molecular karyotypes. These chromosomes appear prone to substantial size alterations associated with genetic exchange. Our results for one of the hybrid clones are completely consistent with it being triploid and the product of fusion of haploid and diploid nuclei.
...
PMID:Trisomy and chromosome size changes in hybrid trypanosomes from a genetic cross between Trypanosoma brucei rhodesiense and T. b. brucei. 134 22
Phosphoinositide-specific
phospholipase C
(PI-PLC) has been shown to be transiently activated when plant cells were treated with elicitors. We thus investigated the activity of PI-PLC when soybean cells were infected with the bacterial pathogen Pseudomonas syringae pv. glycinea, by measuring cellular cytosolic inositol 1,4,5-trisphosphate (IP3) levels. We observed that IP3 content decreased in both compatible and incompatible interactions. In vitro phosphatase activities were similar in both water control and infected cells with slightly lower IP3 degradation observed for infected cells, indicating that the reduced IP3 content in infected cells most likely results from reduced PI-PLC activity. We hypothesize that reduced IP3 content following infection may lead to suppression of various
housekeeping
activities of the cells, thus diverting the cellular resources either to the synthesis of defense-related compounds against pathogens, and/or to the growth of pathogens.
...
PMID:Decreased inositol 1,4,5-trisphosphate content in pathogen-challenged soybean cells. 1079 22
For several decades, lithium has been the drug of choice in the long-term treatment of manic-depressive illness, but the molecular mechanism(s) mediating its therapeutic effects remain to be determined. The enzyme myo-inositol monophosphatase (IMPase) in the
phospholipase C
signaling system is inhibited by lithium at therapeutically relevant concentrations, and is a candidate target of lithium's mood-stabilizing action. Two genes encoding human IMPases have so far been isolated, namely IMPA1 on chromosome 8q21. 13-21.3 and IMPA2 on chromosome 18p11.2. Interestingly, several studies have indicated the presence of a susceptibility locus for bipolar disorder on chromosome 18p11.2. IMPA2 is therefore a candidate for genetic studies on both etiology and lithium treatment of manic-depressive illness. Here we report that the genomic structure of IMPA2 is composed of eight exons, ranging in size from 46 bp to 535 bp. The promoter region contains several Sp1 elements and lacks a TATA-box, features typical for
housekeeping
genes. By a preliminary polymorphism screening of exons 2-8 in a sample of 23 Norwegian bipolar patients, we have identified nine single nucleotide polymorphisms (SNPs). Seven of the polymorphisms were located in the introns, one was a silent transition in exon 2 (159T>C) and one was a transition in exon 5 (443G>A) resulting in a predicted amino acid substitution (R148Q). Our data show that even in a small sample of bipolar patients, several variants of the IMPA2 gene can be identified. IMPA2 is therefore an intriguing candidate gene for future association studies of manic-depressive illness.
...
PMID:A human myo-inositol monophosphatase gene (IMPA2) localized in a putative susceptibility region for bipolar disorder on chromosome 18p11.2: genomic structure and polymorphism screening in manic-depressive patients. 1082 45
Burkholderia pseudomallei is the causative agent of melioidosis and represents a potential bioterrorism threat. In the current studies we have examined gene expression in B. pseudomallei in an animal model of acute melioidosis using whole-genome microarrays. Gene expression profiles were generated by comparing transcriptional levels of B. pseudomallei-expressed genes in infected hamster organs including liver, lung, and spleen following intraperitoneal and intranasal routes of infection to those from bacteria grown in vitro. Differentially expressed genes were similar in infected livers irrespective of the route of infection. Reduced expression of a number of
housekeeping
genes suggested a lower bacterial growth rate during infection. Energy production during growth in vivo involved specific biochemical pathways such as isomerization of 3-phosphoglycerate, catabolism of d-glucosamine and inositol, and biosynthesis of particular amino acids. In addition, the induction of genes known to be involved in oxidative phosphorylation including ubiquinol oxidase, ferredoxin oxidoreductase, and formate dehydrogenase enzymes suggested the use of alternative pathways for energy production, while the expression of genes coding for ATP-synthase and NADH-dehydrogenase enzymes was reduced. Our studies have identified differentially expressed genes which include potential virulence genes such as those for a putative
phospholipase C
and a putative two-component regulatory system, and they have also provided a better understanding of bacterial metabolism in response to the host environment during acute melioidosis.
...
PMID:Genome-wide expression analysis of Burkholderia pseudomallei infection in a hamster model of acute melioidosis. 1698 21
The aim of the present study was to investigate transcription dynamics of the
alpha-toxin
-encoding plc gene relative to two
housekeeping
genes (gyrA and rplL) in batch cultures of three Clostridium perfringens strains with low, intermediate, and high levels of
alpha-toxin
production, respectively. The plc transcript level was always low in the low
alpha-toxin
producing strain. For the two other strains, plc transcription showed an inducible pattern and reached a maximum level in the late exponential growth phase. The transcription levels were however inversely correlated to
alpha-toxin
production for the two strains. We propose that this discrepancy is due to differences in plc translation rates between the strains and that strain-specific translational rates therefore must be determined before
alpha-toxin
production can be extrapolated from transcript levels in C. perfringens.
...
PMID:Dynamics of plc gene transcription and alpha-toxin production during growth of Clostridium perfringens strains with contrasting alpha-toxin production. 1955 45
Serine proteases represent an essential part of cellular homeostasis by generating biologically active peptides. In bacteria, proteolysis serves two different roles: a major
housekeeping
function and the destruction of foreign or target cell proteins, thereby promoting bacterial invasion. In the process, other virulence factors such as exotoxins become affected. In Staphylococcus aureus culture supernatant, the pore-forming
alpha-toxin
is cleaved by the coexpressed V8 protease and aureolysin. The oligomerizing and pore-forming abilities of five such spontaneously occurring N- and C-terminal
alpha-toxin
fragments were studied. (3)H-marked
alpha-toxin
fragments bound to rabbit erythrocyte membranes but only fragments with intact C termini, missing 8, 12 and 71 amino acids from their N-terminal, formed stable oligomers. All isolated fragments induced intoxication of mouse adrenocortical Y1 cells in vitro, though the nature of membrane damage for a fragment, degraded at its C terminus, remained obscure. Only one fragment, missing the first eight N-terminal amino acids, induced irreversible intoxication of Y1 cells in the same manner as the intact toxin. Four of the isolated fragments caused swelling, indicating altered channel formation. Fragments missing 12 and 71 amino acids from the N terminus occupied the same binding sites on Y1 cell membranes, though they inhibited membrane damage caused by intact toxin. In conclusion, N-terminal deletions up to 71 amino acids are tolerated, though the kinetics of channel formation and the channel's properties are altered. In contrast, digestion at the C terminus results in nonfunctional species.
...
PMID:Biological relevance of natural alpha-toxin fragments from Staphylococcus aureus. 2015 74
Brain cells continuously produce and release protons into the extracellular space, with the rate of acid production corresponding to the levels of neuronal activity and metabolism. Efficient buffering and removal of excess H
+
is essential for brain function, not least because all the electrogenic and biochemical machinery of synaptic transmission is highly sensitive to changes in pH. Here, we describe an astroglial mechanism that contributes to the protection of the brain milieu from acidification. In vivo and in vitro experiments conducted in rodent models show that at least one third of all astrocytes release bicarbonate to buffer extracellular H
+
loads associated with increases in neuronal activity. The underlying signalling mechanism involves activity-dependent release of ATP triggering bicarbonate secretion by astrocytes via activation of metabotropic P2Y
1
receptors, recruitment of
phospholipase C
, release of Ca
2+
from the internal stores, and facilitated outward HCO
3
-
transport by the electrogenic sodium bicarbonate cotransporter 1, NBCe1. These results show that astrocytes maintain local brain extracellular pH homeostasis via a neuronal activity-dependent release of bicarbonate. The data provide evidence of another important metabolic
housekeeping
function of these glial cells.
...
PMID:Astrocytes regulate brain extracellular pH via a neuronal activity-dependent bicarbonate shuttle. 3303 38