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PubMed1973

Effect of light on ribonucleic Acid metabolism in greening maize leaves.

The effect of illumination on the incorporation of labeled precursors into RNA of dark-grown maize (Zea mays) leaves was studied using either (32)P-phosphate or double labeling with (14)C- and (3)H-uridine. In the dark, label was preferentially incorporated into etioplast ribosomal RNAs. Incorporation into this fraction and into lower molecular weight fractions was strongly and preferentially stimulated by light during the first 2 hours of illumination. The effect persisted after illumination was terminated. The possibility that light-induced alterations in plastid ribosomal RNA metabolism may not be required for chlorophyll accumulation in maize is discussed.Sucrose density gradient analyses of ribosomes and of extracted RNA did not reveal light-induced incorporation of label into messenger-like RNA associated with polyribosomes during brief illumination. However, newly produced RNA which seems to be neither ribosomal RNA nor transfer RNA is detectable after illumination for 2.5 hours or longer.

Journal Article↗

PubMed2001

RNA recovery and detection of mRNA by RT-PCR from preserved prokaryotic samples.

The effectiveness of maintaining prokaryotic RNA in Synechococcus and Pseudomonas cells, fixed in 96% ethanol, 4% paraformaldehyde, or suspended in RNAlater, and held in cold storage for 3 months was compared. Fluorometric determination of the RNA extracted from Synechococcus and Pseudomonas cells indicated that the cell storage treatments tested were equally effective at maintaining their total RNA content. There was not any detectable decrease in the quantity of RNA isolated from the preserved samples during storage. Intact mRNA transcripts of the RuBisCO (rbcL) and nir genes were detected by reverse transcriptase-polymerase chain reaction (RT-PCR) from preserved bacterial cells throughout 3 months of storage. In contrast, RT-PCR failed to amplify the mRNA of the rbcL and nitrite reductase genes in unfixed and/or unpreserved bacterial samples, suggesting that bacterial mRNA can be well maintained during a prolonged storage when cells are preserved properly. In addition, RNAlater is a useful reagent for the storage and maintenance of high quality RNA in unfrozen samples.

Bacteria↗

PubMed2004

Molecular diagnosis of paramyxovirus infection in snakes using reverse transcriptase-polymerase chain reaction and complementary deoxyribonucleic acid:ribonucleic acid in situ hybridization.

Identification of ophidian paramyxovirus (OPMV) nucleic acid was accomplished in 11 of 14 snakes by a reverse transcriptase-polymerase chain reaction (RT-PCR) assay that detected a 153-bp region of the OPMV genome in total RNA extracted from paraffin-embedded tissues and cell culture. The RT-PCR protocol amplified a portion of the OPMV RNA genome, producing a 153-bp complementary DNA (cDNA) product from both fresh and paraffin-embedded tissue samples. In addition, cDNA:RNA in situ hybridization localized OPMV in formalin-fixed, paraffin-embedded tissue specimens to specific tissues and cells. This latter technique increased the degree of specificity with which a diagnosis of OPMV could be made.

Animals↗

PubMed1988

Glucose stimulation of protooncogene expression and deoxyribonucleic acid synthesis in rat islet cell line.

The rat islet cell line, RIN, established from a transplantable, radiation-induced islet cell tumor represents a unique model to study mechanisms in the control of insulin secretion and biosynthesis. In this study, we have examined the effects of glucose on the protooncogene expressioN and cell growth using a clonal strain of RIN cell, RINr, under serum-free and glucose-free conditions. After 24 h pretreatment, cells were treated with different concentrations of glucose for up to 24 h and then subjected to RNA analysis. Agarose gel electrophoresis of total RNA extracts of RINr cells, followed by hybridization with v-myc DNA yielded a 2.4 kilobase c-myc messenger RNA (mRNA) transcripts. After 24 h pretreatment with serum-free and glucose-free medium, RINr cells expressed a low level of c-myc mRNA transcripts. An increase in c-myc transcripts was detectable within 30 min of D-glucose (200 mg/dl) addition, reaching a maximum of 10-fold within 2 h. Glucose stimulated the steady state of c-myc mRNA transcripts in a dose-responsive manner without any change of gamma-actin mRNA levels after 2 h of treatment. The level of c-myc transcripts then declined as the cells proceeded through G1 to the cycle. [3H]Thymidine uptake into DNA was dramatically increased after 24 h of glucose addition, suggesting that glucose itself stimulates DNA synthesis in RINr cells. These results indicate that glucose-induced proliferation of RINr cells is associated with the stimulation of c-myc gene expression.

Animals↗

PubMed1992

Regulation of 3-ketosteroid reductase messenger ribonucleic acid levels and 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4-isomerase activity in rat liver by sex steroids and pituitary hormones.

We have recently characterized three types of complementary DNA clones encoding predicted isoenzymes of the rat 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4 isomerase (3 beta-HSD) family. Transient expression in nonsteroidogenic cells reveals that the type III isoenzyme specific for male liver does not display oxidative activity for classical substrates of 3 beta-HSD, in contrast to the two other 3 beta-HSD isoenzymes, thus showing exclusively 3-ketosteroid reductase (3-KSR) activity. In order to better understand the sex-specific control of 3 beta-HSD activity and type III 3-KSR gene expression in rat liver, we have studied in adult animals of both sexes the effect of sex steroids and hypophysectomy, pituitary implants, PRL, and GH on type III 3-KSR messenger RNA (mRNA) levels and 3 beta-HSD/delta 5-delta 4 isomerase activity as measured by the conversion of [14C]dehydroepiandrosterone into [14C] delta 4-androstenedione. Ribonuclease protection assay using types I-, II-, and III-specific complementary RNA probes reveals that type III transcripts are the only species detectable in liver RNA extracted from intact males, whereas no hybridization signal was detectable with any of the three probes in intact female liver RNA. In males, 15 days after castration, liver type III 3-KSR mRNA levels decreased by 80% compared to intact controls, whereas 3 beta-HSD activity was reduced by 48%. Administration of dihydrotestosterone (DHT) increased by 8.25-fold type III 3-KSR mRNA concentration and completely reversed the inhibitory effect of orchiectomy on 3 beta-HSD activity. In ovariectomized animals, treatment with DHT markedly increased type III 3-KSR mRNA accumulation and 3 beta-HSD activity, thus leading to values similar to those measured in intact males. Simultaneous treatment with 17 beta-estradiol almost completely abolished the stimulatory effect of DHT in female rats, whereas no significant effect was seen in males. Twenty-four days after hypophysectomy, type III 3-KSR mRNA levels were decreased by 50-55% in males, whereas in females these transcripts markedly increased from undetectable to 28-36% of the value measured in intact male rats. Treatment with DHT or 17 beta-estradiol for a period of 9 days starting 15 days after hypophysectomy had no effect in male and female rats. On the other hand, treatment with ovine PRL (1 mg, twice daily) had no effect in males but completely blocked the elevation of type III 3-KSR mRNA levels and 3 beta-HSD activity observed after hypophysectomy in females.(ABSTRACT TRUNCATED AT 400 WORDS)

3-Hydroxysteroid Dehydrogenases↗

PubMed1996

Pituitary activin receptor subtypes and follistatin gene expression in female rats: differential regulation by activin and follistatin.

The activins, hormones produced in the gonads and extragonadal tissues (including the pituitary), rapidly increase FSH beta messenger RNA (mRNA) and FSH secretion. In the rat, activin acts via a family of activin receptor (ActR) subunits that includes at least one type I (ActRI or ALK-2) and two homologous type II (IIA and IIB) subunits. We have previously reported that ActRIIA mRNA rises after ovariectomy (OVX). Potentially, the OVX-induced increases in ActR mRNAs could result from altered activin or the activin-binding protein follistatin. It was the purpose of the current studies to determine whether activin and/or follistatin regulated activin receptor subunit mRNAs. Adult female rat pituitaries were dissociated and plated for 48 h, transferred to wells containing follistatin or activin for 2 or 24 h, then RNA extracted for measurement of ActRI, IIA, and IIB and follistatin mRNAs. All three ActR mRNAs were easily detectable in pituitary RNA, with the relative abundance of ActRI > IIA >> IIB (18:9:1). Between 2-24 h, levels of all three ActR mRNAs increased 2- to 3-fold in wells containing medium alone, whereas levels of follistatin mRNA were unchanged. Follistatin significantly reduced FSH secretion and follistatin mRNA, but not the ActR mRNAs. Activin increased ActRI (4-fold, at 2 h), ActRIIB (2-fold, at 24 h), and follistatin (2-fold, at 24 h) mRNAs and FSH release (2-fold, at 24 h), but did not alter ActRIIA mRNA levels. We conclude that 1) pituitary ActR mRNA expression is under inhibitory tone in vivo, as suggested by the effect of pituitary removal and cell dispersion and an earlier report after OVX. 2) Pituitary-derived activin stimulates follistatin (but not ActR) mRNA production, and additional increases in follistatin mRNA can be induced by exogenous activin. 3) Higher concentrations of activin differentially regulate pituitary ActR mRNA expression, suggesting that activin exerts a positive feedback effect on its own receptor.

Activin Receptors↗

PubMed1978

Role of intracisternal A-particles and of RNA molecules in plasmacytoma-associated immunodeficiency.

A subcellular fraction from murine plasmacytoma cells was shown to suppress the primary antibody response when injected into normal mice. The active subcellular fraction copurified with intracisternal A-particles. The RNA extracted from subcellular fractions enriched in A-particles was also immunosuppressive. This activity was due to a population of RNA molecules that contained polyadenylic acid. Upon fractionation on a sucrose gradient, two populations of immunosuppressive RNA were obtained with sedimentation velocities of 12 to 18S and 40 to 50S. The 40 to 50S RNA was shown to be a thermolabile aggregate of molecules that contained the 12 to 18S RNA molecules. Plasmacytoma-derived material with similar physicochemical characteristics had previously been shown to induce in normal mouse lymphocytes surface immunoglobulins with the plasmacytoma idiotype, supporting the possibility that one of the mechanisms responsible for the development of immunological deficiency is the change of surface immunoglobulins of nonmalignant B-cells.

Animals↗

PubMed1986

Noninvasive spectroscopic analysis of fluoropyrimidine metabolism in cultured tumor cells.

Nuclear magnetic resonance spectroscopy is a technique that may be used noninvasively to follow the intracellular metabolism of fluorinated antimetabolites such as 5-fluorouracil (FUra) and 5-fluorouridine. Intracellular 19F spectral peaks are assigned by comparison with the pH-dependent chemical shifts measured for eight commercially available fluoropyrimidine metabolites as well as by comparison with the literature recorded values of five known catabolites of FUra. Five murine and human tumor cell lines (N1S1, Sarcoma 180, L1210, HL-60, and Mia-PaCa) were exposed in vitro for 24 h to cytostatic doses of FUra or 5-fluorouridine. Treated cells were harvested and analyzed immediately or following a subsequent incubation under either nutrient-rich or nutrient-poor conditions. A major narrow component peak at 4.6-4.9 ppm was observed in all cell samples analyzed immediately after treatment. This peak was identified as intracellular FUra nucleotides, and its T1 value was approximately 800 ms. No fluoropyrimidine catabolites were detectable in any of the treated cell lines. Free FUra could be measured in cells only after subsequent incubation under nutrient-poor conditions, and this was associated with a decline in the prominent FUra nucleotide peak. In treated cells chased with drug-free media containing 1 microM thymidine, spectra revealed a broad component signal underlying and downfield from the narrow nucleotide-containing peak. By biochemically fractionating treated cells into an acid-soluble fraction and phenol-purified cytoplasmic and nuclear RNA extracts, we were able to completely separate the nucleotide peak from the broad component signal resulting from FUra incorporation into RNA. Thymidine produced a marked enhancement of this 19F signal into both cytoplasmic and nuclear RNA without affecting the nucleotide signal from the acid-soluble fraction. The present ability of nuclear magnetic resonance to monitor the metabolic channeling of fluoropyrimidines in intact tumor cells suggests that future spectroscopic imaging of patients treated with fluorinated antimetabolites may provide clinically important information about tumor biochemistry and drug sensitivity.

Animals↗

PubMed1986

HLA-DR-associated invariant chain is highly expressed in chronic lymphocytic leukemia.

Total RNA extracted from peripheral blood lymphocytes of a patient with B-cell chronic lymphocytic leukemia (CLL) and the poly (A+) RNA was purified. A cDNA library was constructed and approximately 4,000 clones were screened in order to identify genes preferentially expressed in CLL. A relatively low repetition frequency characterizes the majority of the abundant mRNA species present in CLL lymphocytes. One clone, corresponding to the mRNA encoding the HLA-DR-associated invariant chain, was selected and its expression was examined in different leukemic cell populations and in normal tissues. DNA-RNA hybridization studies showed that the invariant chain mRNA (In-mRNA) is detectable in RNA preparations from human blood cells and their precursors, whereas no In-mRNA is found in several other tissues examined. Among various normal and leukemic leukocyte populations, the highest levels of In-mRNA are found in CLL. Therefore, a role of In-chain mRNA as a marker of CLL is proposed. Our data support a relationship between high levels of invariant chain mRNA and the out of cycle condition of CLL peripheral blood lymphocytes.

Clone Cells↗

PubMed1981

RNA inhibits estrogen receptor binding to DNA.

Cytosol from MTW9 rat mammary tumor contains a high molecular weight inhibitor of estrogen receptor binding to DNA. RNase treatment of crude preparations destroys inhibitory activity, whereas DNase or trypsin treatment are without affect, suggesting that some RNA molecule might be involved; in addition, RNA extracted from tumor cytosol was an effective inhibitor of estrogen receptor binding to DNA. A number of synthetic and natural RNA species were analyzed for inhibitory activity; a definite specificity was observed, with poly(G) > poly(U) > poly(A) or poly(C).

Animals↗

PubMed1998

Uterine androgen receptor mRNA expression in metestrous and anestrous bitches being healthy or suffering from Pyometra.

The importance of androgens for the female reproductive system has been investigated for decades and a number of androgen sensitive processes has now been identified in female reproductive organs. For carnivore species no data were available so far about uterine androgen sensitivity and its regulation. The present study therefore aimed to investigate whether androgen receptors (AR) are present in the dog uterus, whether they are regulated throughout the ovarian cycle and whether pyometra affects their expression rate. Uterine tissue samples were collected from 28 bitches of different ages and various breeds. The samples were grouped according to the stage of estrous cycle (metestrus ME or anestrus AE) and the pathological status of the uterus (i.e. suffering from pyometra or not). Androgen receptor mRNA (AR mRNA) was quantified from 500 ng of total RNA isolated from the tissue samples using an internally standardized reverse transcription polymerase chain reaction (RT-PCR) described previously. The amount of total RNA extractable per g tissue was elevated during pyometra. The successful amplification of the expected 172 bp fragment from canine uterine RNA together with the confirmation of the identity of this fragment by sequence analysis, demonstrates that AR is expressed in this particular tissue. Comparing the expression rates in uteri from bitches during ME or AE being healthy (H) or suffering from pyometra (P), the only significant (p < 0.01) difference was found between H and P uteri during ME with 3.5-fold lower expression rates in P. Although the same seems true for AE bitches, a significant difference could not be demonstrated due to the low number (n = 2) of diseased animals in the AE group. There was no evident effect of the stage of ovarian cycle on uterine AR mRNA levels.

Anestrus↗

PubMed2005

Influence of different Oryza cultivars on expression of nifH gene pools in roots of rice.

Cultivation-independent studies suggest that roots of rice (Oryza sativa) are colonized by a diverse community of nitrogen-fixing bacteria. Here we report for the first time mRNA-based profiling of nitrogenase (nifH) genes, to study the impact of lowland-rice genotypes at the cultivar level on the functional diversity of root-associated diazotrophs. Root RNA extracts from all plants contained nifH mRNA at levels detectable by reverse transcription polymerase chain reaction (RT-PCR). Terminal restriction fragment length polymorphism (T-RFLP) analysis of RT-PCR products showed only small interplant variations. However, RNA- and DNA-based profiles obtained from the same root extractions differed from each other, suggesting that presence of diazotrophs did not necessarily coincide with active transcription of nif genes. Application of N-fertilizer at planting had a long-term effect on the profile of expressed nitrogenase genes. Phylogenetic analysis of a clone library constructed for nifH fragments expressed in wild species of rice roots indicated that active diazotrophs were not related to cultured strains. The composition of active diazotrophic communities was compared for six related cultivars of O. sativa, wild species Oryza brachyantha, and a genetic cross between it and cv. IR56, grown under identical conditions in rice field soil in the Philippines without N-fertilizer application. Remarkable varietal differences in root associated nifH-gene expressing communities were detected. This underlines the importance of mRNA-based approaches to study functional diversity and eventually identify key diazotrophs in a particular environment.

Bacteria↗

PubMed2002

Stabilization of mRNA expression in whole blood samples.

BACKGROUND: Accurate quantification of mRNA in whole blood is made difficult by the simultaneous degradation of gene transcripts and unintended gene induction caused by sample handling or uncontrolled activation of coagulation. This study was designed to compare a new blood collection tube (PAXgene Blood RNA System) and a companion sample preparation reagent set with a traditional sample collection and preparation method for the purpose of gene expression analysis. METHODS: We collected parallel blood samples from healthy donors into the new sample collection tubes and control EDTA tubes and performed serial RNA extractions on samples stored for 5 days at room temperature and for up to 90 days at 4 and 20 degrees C. Samples were analyzed by Northern blot analysis or reverse transcription-PCR (RT-PCR). RESULTS: Specific mRNA concentrations in blood stored in EDTA tubes at any temperature changed substantially, as determined by high-precision RT-PCR. These changes were eliminated or markedly reduced when whole blood was stored in PAXgene tubes. Loss of specific mRNAs, as measured by RT-PCR, reflected total RNA depletion as well as specific mRNA destruction demonstrated by Northern blot analysis. The salutary effects of PAXgene on mRNA stabilization extended to blood samples from eight unrelated donors. CONCLUSIONS: Compared with whole blood collected in EDTA tubes and extracted by an organic method, the PAXgene Blood RNA System reduced RNA degradation and inhibited or eliminated gene induction in phlebotomy whole blood samples. Storage of whole blood samples in PAXgene tubes can be recommended for clinically related blood samples that will be analyzed for total or specific RNA content.

Blood Specimen Collection↗

PubMed2006

[An application of laser capture microdissection to isolate the pure atrial cells].

OBJECTIVE: To use the laser capture microdissection (LCM) to isolate the pure atrial cells from heart. To extract tiny amount RNA and amplify the genes of beta-actin and GAPDH. METHODS: First, the prepared sample RNA was extracted and verified. Second, the frozen sections were scraped after haematoxylin-eosin staining, and then the RNA of scraped tissues was extracted and verified. Last, the tiny amount RNA was extracted from atrial cells captured by LCM, and the genes of beta-actin and GAPDH were amplified by reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: The atrial cells isolated with LCM had clear morphology after quick staining. The high quality RNA was extracted from LCM sample and scraped tissues, of which A260/A280 was 1.9-2.0. And 18S rRNA and 28S rRNA were seen distinctly on the gel of RNA formaldehyde denaturing gel electrophoresis, which indicated that RNA didn't degrade before cells captured. Too small amount of RNA extracted from captured cells was below the detectable limit of gel electrophoresis or ultraviolet spectrophotometer. Bands of 300 bp and 357 bp could be amplified by RT-PCR from tiny amount RNA. CONCLUSION: Highly pure atrial cells could be obtained by LCM. Tiny amount RNA of captured atrial cells could be extracted and amplified with genes of beta-actin and GAPDH.

Actins↗

PubMed1976

In vivo and in vitro synthesis of adenovirus type 2 early proteins.

The synthesis of adenovirus type 2 (Ad2)-induced early polypeptides was examined in vivo and in vitro by a combination of sodium dodecyl sulfate-polyacrylamide gel electrophoresis alone and specific immunoprecipitation followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Analysis of total [35S]methionine-labeled polypeptides synthesized in vivo at 3 h postinfection allowed us to detect in infected cells at lease 13 distinct polypeptides that are either absent or less conspicuous in extracts from mock-infected cells. These Ad2-induced early polypeptides have molecular weights ranging from 72 x 10(3) to 10.5 x 10(3) and have accordingly been designated as E72K to E10.5K. Nine of the in vivo synthesized early polypeptides can be precipitated specifically from infected cell extracts by antisera with specificity against early adenovirus proteins. In vitro translation of mRNA extracted from mock-infected cells and from Ad2-infected cells was carried out in preincubated Ehrlich ascites cell extracts. All the early Ad2-induced polypeptides identified in the extracts from infected cells labeled in vivo were also detected among the polypeptides immunoprecipitated specifically from the in vitro reaction mixtures programmed by RNA extracted at 4 h postinfection from Ad2-infected cells.

Adenoviridae↗

PubMed1986

Molecular cloning of mRNAs expressed specifically during spherulation of Physarum polycephalum.

A cDNA library was constructed using the poly(A)+ RNA extracted from spherulating Physarum polycephalum microplasmodia. This library (740 clones) was screened by differential hybridization with 32P-labeled poly(A)+ RNA from growing plasmodia and developing spherules. The results showed that at least 30% of the clones corresponded to mRNAs expressed specifically in spherulating plasmodia. The 35 spherulation-specific cDNA clones giving the strongest hybridization signals were analysed. From this group, four different sequences complementary to very abundant mRNAs were identified. They each accounted for 1.5% of 4.5% of all the clones in the library and probably represented the most abundant spherulation-specific mRNAs. In addition, four less abundant mRNAs were identified from stage-specific clones giving weaker hybridization signals. These sequences represented individually between 0.3% and 0.7% of the clones in the library. Northern blots showed that these eight different sequences were absent from plasmodia and were most abundant 24-36 h after the induction of spherulation. Similar results were also obtained when spherulation was induced by the addition of a sublethal concentration of ferrous iron ions to the growth medium. Hybridization of the spherule-specific clones to Southern blots of genomic DNA suggested the presence of one copy for each gene.

Cloning, Molecular↗

PubMed1992

Evidence for the existence of RNA of Ca(2+)-channel alpha 2/delta subunit in Xenopus oocytes.

Ba(2+)-currents (IBa) through voltage-dependent Ca(2+)-channels were studied in Xenopus oocytes injected with RNA from several excitable tissues, using the two-electrode voltage-clamp technique. Previous studies have shown that the expression of cardiac Ca(2+)-channels can be suppressed by an hybrid-arrest procedure that includes co-injection of the tissue-derived RNA with an 'antisense' oligonucleotide complementary to a part of RNA coding for the Ca(2+)-channel alpha 1 subunit. In this study, this method was used to investigate the role of the alpha 2/delta subunit. Co-injection of RNA extracted from either rabbit heart, rat brain or rat skeletal muscle (SkM) with 'antisense' oligonucleotides complementary to the alpha 2/delta subunit RNA did not substantially affect the expression of IBa in the oocytes. Using the Northern blot hybridization method, it was shown that native oocytes contain large amounts of alpha 2/delta subunit RNA of Ca(2+)-channel. It is proposed that te oligonucleotide treatment fails to eliminate the alpha 2/delta RNA because of the vast excess of endogenous alpha 2/delta RNA. These results impose a limit on the use of the hybrid-arrest method.

Animals↗

PubMed1994

Characterization of the platelet-activating factor acetylhydrolase from human plasma by heterologous expression in Xenopus laevis oocytes.

Platelet-activating factor (PAF) has been implicated as a mediator of inflammation and atherosclerosis. A specific degradative enzyme found in plasma, PAF acetylhydrolase, plays important roles in various pathophysiological events induced by PAF. Human macrophages and Hep G2 cells secrete PAF acetylhydrolase with characteristics identical to the plasma activity. Other investigators reported that apolipoprotein B may possess phospholipase A2 activity, which suggested that apolipoprotein B might be a zymogen for PAF acetylhydrolase. However, while macrophages express PAF acetylhydrolase activity, we did not detect cDNAs for apolipoprotein B in a cDNA library from these cells, indicating that macrophages do not express this protein. In contrast, Hep G2 cells had high levels of cDNA for apolipoprotein B, as expected. We next injected Xenopus laevis oocytes with poly(A)+ RNA extracted from cultured human macrophages and Hep G2 cells. Twenty-five to 50% of Xenopus oocytes injected with poly(A)+ RNA from macrophages or Hep G2 cells secreted a PAF acetylhydrolase activity (1.0-7.8 nmol/ml per h) that also utilized a synthetic oxidized phospholipid as substrate. The activity secreted by poly(A)+ RNA-injected oocytes associated with lipoproteins and transferred between the particles in a pH-dependent manner, much like the plasma activity. These experiments establish that the properties of the enzyme released from poly(A)+ RNA-injected oocytes are identical to those of the plasma form of PAF acetylhydrolase and that the activity detected is not the expression of a domain in apolipoprotein B.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗