A comprehensive two-hybrid analysis to explore the yeast protein interactome

Protein-protein interactions play crucial roles in the execution of various biological functions. Accordingly, their comprehensive description would contribute considerably to the functional interpretation of fully sequenced genomes, which are flooded with novel genes of unpredictable functions. We previously developed a system to examine two-hybrid interactions in all possible combinations between the approximately 6,000 proteins of the budding yeast Saccharomyces cerevisiae. Here we have completed the comprehensive analysis using this system to identify 4,549 two-hybrid interactions among 3,278 proteins. Unexpectedly, these data do not largely overlap with those obtained by the other project [Uetz, P., et al. (2000) Nature (London) 403, 623-627] and hence have substantially expanded our knowledge on the protein interaction space or interactome of the yeast. Cumulative connection of these binary interactions generates a single huge network linking the vast majority of the proteins. Bioinformatics-aided selection of biologically relevant interactions highlights various intriguing subnetworks. They include, for instance, the one that had successfully foreseen the involvement of a novel protein in spindle pole body function as well as the one that may uncover a hitherto unidentified multiprotein complex potentially participating in the process of vesicular transport. Our data would thus significantly expand and improve the protein interaction map for the exploration of genome functions that eventually leads to thorough understanding of the cell as a molecular system.

Circadian oscillation of a mammalian homologue of the Drosophila period gene

Many biochemical, physiological and behavioural processes in organisms ranging from microorganisms to vertebrates exhibit circadian rhythms. In Drosophila, the gene period (per) is required for the circadian rhythms of locomotor activity and eclosion behaviour. Oscillation in the levels of per mRNA and Period (dPer) protein in the fly brain is thought to be responsible for the rhythmicity. However, no per homologues in animals other than insects have been identified. Here we identify the human and mouse genes (hPER and mPer, respectively) encoding PAS-domain (PAS, a dimerization domain present in Per, Amt and Sim)-containing polypeptides that are highly homologous to dPer. Besides this structural resemblance, mPer shows autonomous circadian oscillation in its expression in the suprachiasmaticnucleus, which is the primary circadian pacemaker in the mammalian brain. Clock, a mammalian clock gene encoding a PAS-containing polypeptide, has now been cloned: it is likely that the Per homologues dimerize with other molecule(s) such as Clock through PAS-PAS interaction in the circadian clock system.

Toward a protein-protein interaction map of the budding yeast: A comprehensive system to examine two-hybrid interactions in all possible combinations between the yeast proteins

Protein-protein interactions play pivotal roles in various aspects of the structural and functional organization of the cell, and their complete description is indispensable to thorough understanding of the cell. As an approach toward this goal, here we report a comprehensive system to examine two-hybrid interactions in all of the possible combinations between proteins of Saccharomyces cerevisiae. We cloned all of the yeast ORFs individually as a DNA-binding domain fusion ("bait") in a MATa strain and as an activation domain fusion ("prey") in a MATalpha strain, and subsequently divided them into pools, each containing 96 clones. These bait and prey clone pools were systematically mated with each other, and the transformants were subjected to strict selection for the activation of three reporter genes followed by sequence tagging. Our initial examination of approximately 4 x 10(6) different combinations, constituting approximately 10% of the total to be tested, has revealed 183 independent two-hybrid interactions, more than half of which are entirely novel. Notably, the obtained binary data allow us to extract more complex interaction networks, including the one that may explain a currently unsolved mechanism for the connection between distinct steps of vesicular transport. The approach described here thus will provide many leads for integration of various cellular functions and serve as a major driving force in the completion of the protein-protein interaction map.

Herbivory-induced volatiles elicit defence genes in lima bean leaves

In response to herbivore damage, several plant species emit volatiles that attract natural predators of the attacking herbivores. Using spider mites (Tetranychus urticae) and predatory mites (Phytoseiulus persimilis), it has been shown that not only the attacked plant but also neighbouring plants are affected, becoming more attractive to predatory mites and less susceptible to spider mites. The mechanism involved in such interactions, however, remains elusive. Here we show that uninfested lima bean leaves activate five separate defence genes when exposed to volatiles from conspecific leaves infested with T. urticae, but not when exposed to volatiles from artificially wounded leaves. The expression pattern of these genes is similar to that produced by exposure to jasmonic acid. At least three terpenoids in the volatiles are responsible for this gene activation; they are released in response to herbivory but not artificial wounding. Expression of these genes requires calcium influx and protein phosphorylation/dephosphorylation.

Involvement of jasmonate- and salicylate-related signaling pathways for the production of specific herbivore-induced volatiles in plants

We compared volatiles from lima bean leaves (Phaseolus lunatus) infested by either beet armyworm (Spodoptera exigua), common armyworm [Mythimna (Pseudaletia) separata], or two-spotted spider mite (Tetranychus urticae). We also analyzed volatiles from the leaves treated with jasmonic acid (JA) and/or methyl salicylate (MeSA). The volatiles induced by aqueous JA treatment were qualitatively and quantitatively similar to those induced by S. exigua or M. separata damage. Furthermore, both S. exigua and aqueous JA treatment induced the expression of the same basic PR genes. In contrast, gaseous MeSA treatment, and aqueous JA treatment followed by gaseous MeSA treatment, induced volatiles that was qualitatively and quantitatively more similar to the T. urticae-induced volatiles than those induced by aqueous JA treatment. In addition, T. urticae damage resulted in the expression of the acidic and basic PR genes that were induced by gaseous MeSA treatment and by aqueous JA treatment, respectively. Based on these data, we suggest that in lima bean leaves, the JA-related signaling pathway is involved in the production of caterpillar-induced volatiles, while both the SA-related signaling pathway and the JA-related signaling pathway are involved in the production of T. urticae-induced volatiles.

Gene responses in bean leaves induced by herbivory and by herbivore-induced volatiles

Plant-plant interactions via herbivory-induced leaf volatiles could result in the induction of defense responses against aggressive biotic agents in plants. In this study, cDNA microarray technology showed comprehensive gene activation in lima bean leaves that were exposed to volatiles released from the neighboring leaves infested with spider mites. The infestation with spider mites and the herbivory-induced volatiles enhanced 97 and 227 gene spots on the microarray tip printed with 2032 lima bean cDNA, respectively. These genes are related to such broad functions as responses to pathogenesis, wounding, hormones, ethylene biosynthesis, flavonoid biosynthesis, (post) transcriptional modifications, translations, chaperones, secondary signaling messengers, membrane transports, protein/peptide degradations, and photosynthesis. We therefore conclude that herbivorous damage and herbivory-induced volatiles elicit comprehensive and drastic changes of metabolisms in leaves.

Exogenous ACC enhances volatiles production mediated by jasmonic acid in lima bean leaves

We report the synergistic effects of exogenous 1-aminocyclopropane-1-carboxylic acid (ACC) and jasmonic acid (JA) on production of induced volatiles by excised lima bean leaves. Application of ACC alone to leaves induced trace amounts of volatiles. ACC positively affected three JA-induced volatiles, (E)- and (Z)-beta-ocimene, and (Z)-3-hexenyl acetate. The ethylene inhibitor, silver thiosulfate, inhibited the production of these compounds. The results suggest synergistic effects of JA and ACC on inducible volatile production by lima bean leaves. Furthermore, lima bean leaves treated with JA plus ACC became more attractive to predatory mites, Phytoseiulus persimilis, than those treated with JA alone.

Intracellular transduction in the regulation of pheromone biosynthesis of the silkworm, Bombyx mori: suggested involvement of calmodulin and phosphoprotein phosphatase

We have tested the effects of chemicals on bombykol production in vitro in the silkworm, Bombyx mori, to probe the biochemical steps as well as underlying mechanisms regulated by PBAN. These results suggest the involvement of calmodulin and phosphoprotein phosphatase in the intracellular signal transduction of PBAN action.

Involvement of calcineurin in the signal transduction of PBAN in the silkworm, Bombyx mori (Lepidoptera)

In several moth species sex pheromone production in the pheromone gland is regulated by a neurohormone, pheromone biosynthesis activating neuropeptide (PBAN). In Bombyx mori it is suggested that PBAN, after binding to the cell-surface receptor, primarily activates a plasma membrane receptor-activated Ca2+ channel to increase cytosolic levels of Ca2+, and Ca2+/calmodulin complex directly or indirectly activates a phosphoprotein phosphatase, which in turn elicits activation of acyl CoA reductase (the key enzyme under PBAN control) through dephosphorylation, resulting in pheromone (bombykol) production. The effect of cyclosporin A (CsA) and FK 506, specific inhibitors of calcineurin (phosphoprotein phosphatase 2B) was studied on the sex pheromone production, in B. mori. The in vitro experiments showed that both chemicals exerted a dose-dependent inhibitory action when they were co-incubated with TKYFSPRL amide (Hez-PBAN fragment peptide). Practically, no difference was detected between the two chemicals in the tested doses (0.025-1250 microM). When effects of CsA or FK 506 were studied on cell-free production of bombykol by using microsomal fraction no inhibition was detected. Since microsomal fraction contains the acyl CoA synthetase, the rate-limiting acyl CoA reductase and the precursor, bombykol is produced if supplied with CoA, ATP and NADPH. Thus, the inhibitory action of CsA and FK506 under in vitro conditions should occur before the step of acyl group reduction and the effect is likely to be attributable to the inhibition of calcineurin in the signal transduction cascade mechanism of PBAN, in B. mori. The existence of calcineurin in the pheromone gland by using Western blot analysis is also demonstrated.

Intracellular signal transduction of PBAN action in lepidopteran insects: inhibition of sex pheromone production by compactin, an HMG CoA reductase inhibitor

Pheromone biosynthesis activating neuropeptide (PBAN) regulates sex pheromone production in the pheromone glands of many species of female moths. In order to probe the biochemical steps as well as underlying mechanisms regulated by PBAN, we have tested the effect of chemicals on sex pheromone production by using an in vitro assay. Among the chemicals we tested here, compactin, a specific 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitor, clearly inhibited the pheromone biosynthesis in the silkworm, Bombyx mori, and the common cutworm, Spodoptera litura. Since the activation of HMG CoA reductase occurs by dephosphorylation mediated by a specific phosphatase and the biochemical step regulated by PBAN in bombykol biosynthesis is similar to the one catalyzed by HMG-CoA reductase in cholesterol biosynthesis, the present results support the idea that phosphoprotein phosphatase has a significant role to regulate bombykol production in the intracellular transduction of PBAN action in B. mori.

Intracellular signal transduction of PBAN action in the silkworm, Bombyx mori: involvement of acyl CoA reductase

In the silkworm, Bombyx mori, production of the sex pheromone bombykol is regulated by a neurohormone termed PBAN. We have detected the activity of acyl CoA reductase in the pheromone gland of B. mori by using palmitoyl CoA as a substrate. The acyl CoA reductase requires NADPH, but not NADH, as a proton dono. When the pheromone gland was incubated with the PBAN fragment peptide TKYFSPRLamide, palmitoyl CoA was incorporated and converted into the corresponding C16 alcohols. Radio HPLC analysis revealed that these C16 alcohols were hexadecan-1-ol (81.2%), (Z)-11-hexadecen-1-ol (12.3%), and (E, Z)-10, 12-hexadecadien-1-ol (= bombykol, 6.5%). The production of C16 alcohols in the pheromone gland was inhibited by the known bombykol biosynthesis inhibitors EDTA, LaCl3, W-7, trifluoperazine, p-nitrophenyl phosphate, NaF and compactin. By contrast, when the pheromone gland homogenate was incubated in the presence of palmitoyl CoA and NADPH, production of C16 alcohols was affected by compactin, W-7 and trifluoperazine, but not by EDTA, LaCl3, p-nitrophenyl phosphate and NaF. These results indicate that compactin, W-7 and trifluoperazine directly suppress the step catalyzed by acyl CoA reductase, whereas EDTA, LaCl3, pNPP, and NaF inhibit bombykol production by affecting other biochemical steps in the signal transduction of PBAN action. The present results also imply that PBAN regulates the step catalyzed by acyl CoA reductase and that palmitoyl CoA could be used as a substrate of the acyl CoA reductase that regulates bombykol biosynthesis.

Bioactivity of natural O-prenylated phenylpropenes from Illicium anisatum leaves and their derivatives against spider mites and fungal pathogens

A variety of volatile phenylpropenes, C6-C3 compounds are widely distributed in the plant kingdom, whereas prenylated phenylpropenes are limited to a few plant species. In this study, we analysed the volatile profiles from Illicium anisatum leaves and identified two O-prenylated phenylpropenes, 4-allyl-2-methoxy-1-[(3-methylbut-2-en-1-yl)oxy]benzene [O-dimethylallyleugenol (9)] and 5-allyl-1,3-dimethoxy-2-(3-methylbut-2-en-1-yl)oxy]benzene [O-dimethylallyl-6-methoxyeugenol (11)] as major constituents. The structure-activity relationship of a series of eugenol derivatives showed that specific phenylpropenes, including eugenol (1), isoeugenol (2) and 6-methoxyeugenol (6), with a phenolic hydroxy group had antifungal activity for a fungal pathogen, whereas guaiacol, a simple phenolic compound, and allylbenzene had no such activity. The eugenol derivatives that exhibited antifungal activity, in turn, had no significant toxicant property for mite oviposition. Interestingly, O-dimethylallyleugenol (9) in which the phenolic oxygen was masked with a dimethylallyl group exhibited a specific, potent oviposition deterrent activity for mites. The sharp contrast in structural requirements of phenylpropenes suggested distinct mechanisms underlying the two biological activities and the importance of a phenolic hydroxy group and its dimethylallylation for the structure-based design of new functional properties of phenylpropenes.

NLRP3 inflammasome is involved in testicular inflammation induced by lipopolysaccharide in mice

PROBLEM

Systemic inflammation induced by infection, which is associated with testicular inflammation, predisposes males to subfertility. Recently, the nucleotide-binding oligomerization domain, leucine-rich repeat-, and pyrin domain-containing 3 (NLRP3) inflammasome was identified as a key mediator of inflammation, and excessive activation of the NLRP3 inflammasome was shown to contribute to the pathogenesis of a wide variety of diseases. However, the mechanisms underlying infectious inflammation in the testis remain unclear. We investigated the effect of lipopolysaccharide (LPS)-induced systemic inflammation on the role of the NLRP3 inflammasome in murine testes.

METHOD OF STUDY

We performed in vivo and in vitro studies using an LPS-induced model of NLRP3 inflammasome activation and testicular inflammation.

RESULTS

Intraperitoneal administration of LPS significantly impaired sperm motility in the epididymis of wild type (WT) and NLRP3-knockout (KO) mice. LPS administration stimulated interleukin (IL)-1β production and secretion in the testes of WT mice, and these adverse effects were improved in the testes of NLRP3-KO mice. LPS administration also stimulated neutrophil infiltration as well as its chemoattractant C-C motif chemokine ligand 2 (CCL2) in WT testes, which were suppressed in NLRP3-KO testes. In in vitro cell culture, treatment with LPS and NLRP3 inflammasome activation significantly induced IL-1β and CCL2 secretion from WT but not NLRP3-KO testicular cells.

CONCLUSIONS

Taken together, our results suggest that testicular cells have the potential to secrete IL-1β and CCL2 in an NLRP3 inflammasome-dependent manner and that these cytokines from the testis may further exacerbate testicular function, resulting in subfertility during infectious diseases.

Advanced maternal age induces fetal growth restriction through decreased placental inflammatory cytokine expression and immune cell accumulation in mice

Advanced maternal age is a risk factor for female infertility, and placental dysfunction is considered one of the causes of pregnancy complications. We investigated the effects of advanced maternal aging on pregnancy outcomes and placental senescence. Female pregnant mice were separated into three groups: young (3 months old), middle (8–9 months old), and aged (11–13 months old). Although the body weights of young and middle dams gradually increased during pregnancy, the body weight of aged dams only increased slightly. The placental weight and resorption rate were significantly higher, and live fetal weights were reduced in a maternal age-dependent manner. Although mRNA expression of senescence regulatory factors (p16 and p21) increased in the spleen of aged dams, mRNA expression of p16 did not change and that of p21 was reduced in the placenta of aged dams. Using a cytokine array of proteins extracted from placental tissues, the expression of various types of senescence-associated secretory phenotype (SASP) factors was decreased in aged dams compared with young and middle dams. The aged maternal placenta showed reduced immune cell accumulation compared with the young placenta. Our present results suggest that models using pregnant mice older than 8 months are more suitable for verifying older human pregnancies. These findings suggest that general cellular senescence programs may not be included in the placenta and that placental functions, including SASP production and immune cell accumulation, gradually decrease in a maternal age-dependent manner, resulting in a higher rate of pregnancy complications.

Cell-free production of the silkworm sex pheromone bombykol

Cell-free production of bombykol was done by incubating a pheromone gland homogenate in the presence of NADPH, ATP, and CoA. Addition of n-hexane to the reaction mixture stimulated bombykol production, resulting in production of 238 ng of bombykol from the homogenate equivalent to 2 pheromone glands after 23 h. Removal of either NADPH, ATP, or CoA resulted in no stimulation of bombykol production, suggesting that the final step of the bombykol biosynthetic pathway is done by acyl CoA synthetase and reductase, sequentially. Incubation first with ATP or high concentrations of ATP suppressed the production of bombykol. Since incubation with ATP also inhibited conversion of [1-14C]palmitoyl CoA into 1-hexadecanol, the inhibitory action of ATP seemed attributable to inactivation of the acyl CoA reductase by phosphorylation, as mediated by a protein kinase in the homogenate. Our results suggest that the activity of acyl CoA reductase in bombykol biosynthesis is regulated by phosphorylation/dephosphorylation, and that the activation occurs by dephosphorylation as mediated by phosphoprotein phosphatase.

Intracellular signal transduction of PBAN action in the common cutworm, Spodoptera litura: effects of pharmacological agents on sex pheromone production in vitro

Pheromone biosynthesis activating neuropeptide (PBAN) regulates sex pheromone production in the pheromone glands of many species of female moths. In order to probe the biochemical steps as well as underlying mechanisms regulated by PBAN, we have tested the effects of pharmacological agents on sex pheromone production of the common cutworm, Spodoptera litura, using an in vitro assay. Among the pharmacological agents we tested, ionomycin (calcium ionophore) alone stimulated sex pheromone production, while LaCl3 (calcium channel blocker), W-7, trifluoperazine (calmodulin inhibitor), NaF, and p-nitrophenyl phosphate (phosphatase inhibitor) suppressed the pheromone production by a pheromonotropic peptide, TKYFSPRLamide. By contrast, forskolin (adenylate cyclase activator), phorbol 12-myristate 13-acetate (protein kinase C activator), and cyclic nucleotides alone failed to stimulate sex pheromone production. These results suggest that Ca2+/calmodulin complex and phosphoprotein phosphatase are involved in the signal transduction of PBAN action in S. litura.

Expression of heat shock proteins, Hsp70 and Hsp25, in the rat gingiva after irradiation with a CO2 laser in coagulation mode

BACKGROUND AND OBJECTIVE

The therapeutic rationale of low-energy pulsed CO(2) laser coagulation mode has not been clarified yet. We conducted this study to characterize the effect of low-energy pulsed CO(2) laser coagulation mode irradiation of the rat gingiva in terms of the expression of heat shock proteins.

MATERIAL AND METHODS

Laser irradiation was achieved with the parameters of 5 W, 600 mus pulse duration, and fluence of 326 J/cm(2). The gingiva dissected at different times after irradiation was processed for immunohistochemical examination of the expression of the heat shock proteins, Hsp70 and Hsp25.

RESULTS

One hour after irradiation, the epithelial keratinocytes facing the laser wound exhibited an overexpression of Hsp70 in their nucleus. The connective tissue cells facing the laser wound, which included fibroblasts and capillary endothelial cells, showed de novo expression of Hsp70 at 3 h post-irradiation, the level of which peaked at 1 d and thereafter decreased. An enhanced and/or de novo expression of Hsp25 in the connective tissue cells facing the laser wound became evident at 3 h after irradiation, and after 1 d the Hsp25-expressing cells increased in number and spread over the wound as wound repair progressed. There was a temporospatial difference in the expression pattern between Hsp70 and Hsp25, with only a few cells appearing to co-express both heat shock proteins.

CONCLUSION

The CO(2) laser treatment in coagulation mode produced the expression of heat shock proteins, and the findings suggest that while Hsp70 mainly conferred cell protection, Hsp25 was involved in the progress of wound repair as well as cell protection.

Growth in methylcellulose of human mast cells in hematopoietic colonies stimulated by steel factor, a c-kit ligand

We examined the effect of Steel factor (SLF) on the development of human mast cells in hematopoietic colonies from cord blood mononuclear cells in methylcellulose culture. When cord blood cells were cultured for 3 weeks, SLF increased the cellular tryptase levels detected in total cultured cells. It also stimulated the formation of small-cell colonies consisting mainly of polymorphonuclear granulocytes and immature blastoid cells in a concentration-dependent manner but not the formation of colonies consisting of large macrophagic cells. A low percentage of tryptase-positive mast-cell-like cells was found in 39 out of 100 granulocyte/blastoid cell colonies. Four of the 100 colonies contained 10-20% tryptase-positive cells, but we failed to observe colonies consisting of > 20% of tryptase-positive cells. These results suggest that the effect of SLF on mast cell growth is brought on by stimulating the growth of primitive hematopoietic progenitors.

Severe maternal stress alters placental function, resulting in adipose tissue and liver dysfunction in offspring of mice

The developmental origins of health and disease (DOHaD) hypothesis is that future lifestyle diseases in offspring are associated with intrauterine origins in the mother; stress during pregnancy is a risk factor for these diseases in offspring. This study aimed to clarify association of maternal stress with placental dysfunction and offspring development in mice. We applied water stress for 24 h during late pregnancy to explore the metabolic response of offspring to a normal diet (ND) and high-fat diet (HFD). Placental functions were altered by maternal stress, reducing the birth weight of the offspring. In the later life of offspring fed with ND, maternal stress impaired systemic glucose tolerance and altered adipokine secretion in adipose tissue and/or liver. The female offspring of stress-induced dams were light in body weight with lower adipose tissue and smaller adipocytes in both the ND and HFD groups. Abnormal situations, such as dysregulation of plasma glucose levels and fatty liver despite and lower increases in body weight, were observed in the female offspring of stress-induced dams, especially in the HFD-treated group. These findings suggest that long-lasting abnormal conditions and responses to metabolic challenges in maternal stress-induced offspring are linked to placental dysregulation and fetal programming.

Maternal hypertensive condition alters adipose tissue function and blood pressure sensitivity in offspring

Preeclampsia (PE) is characterized by hypertension, proteinuria, and fetal growth restriction during pregnancy, suggesting that the preeclamptic intrauterine environment may affect the growth and health of the offspring. This study aimed to how maternal hypertension affects male offspring growth, focusing on lipid metabolism and blood pressure in mice. Female mice were infused with angiotensin II (Ang II) on gestational day 12. Dysregulation and accumulation of lipid were observed in the placenta of Ang II-induced maternal hypertensive dams, associating with fetal growth restriction. Ang II-offspring showed lower birth weight than in the control-offspring. Isolated and differentiated adipocyte from neonatal mice of Ang II-dams showed higher Pparγ mRNA expression compared with the control group. Lower body weight tendency had continued in Ang II-offspring during long period, body weight of Ang II-offspring caught up the control-offspring at 16 weeks of age. The adipose tissue of Ang II-offspring in adult also showed higher Pparγ mRNA expression with the accumulation of neutrophils and inflammatory monocytes than in those control. In addition, Ang II-offspring had higher basal blood pressure and higher sensitivity to hypertensive stimuli than in the control-offspring. Taken together, maternal hypertension induced by Ang II changes placental function, causing a lower birth weight. These changes in the intrauterine environment may affect adipocyte function and blood pressure of offspring after growth.

[Inhibition of cholinesterase activity induced by pyridaphenthion]

Inhibitory effects on cholinesterase (ChE) activity in blood of the rabbit induced by pyridaphenthion(PD), an organophosphorus compound, and effects of 2-pyridine aldoxime methiodide(PAM) on this inhibition were examined. 1) Experimental results within 24 hr: An oral administration of each dose of PD(100 approximately 750 mg/kg) gradually decreased ChE activity and ChE activity value decreased to 20.5% in the erythrocytes and 21.5% in the plasma 24 hr after administration of 500 mg/kg of PD. However, this value recovered remarkably with an intravenous injection of PAM. The ChE activity value was 55.5% in the erythrocytes and 41.4% in the plasma with a single injection, and respectively 67.8% and 59.1% when PAM was injected three times. 2) Experimental results for 14 days: Following an increase of the administered dose (100 approximately 400 mg/kg) of PD, a decrease in ChE activity was apparent and a recovery to normal values was delayed. This inhibition could be ameliorated quickly with an injection of PAM. Considering that PAM does not have remarkable detoxicative effects on organophosphorus compounds which have a low toxicity, PAM appears to be a promising antidote against PD.