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1.
Res Nurs Health ; 47(2): 234-241, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38281085

RESUMO

The purpose of this study was to examine the impact of a culturally based intervention, the Intertribal Talking Circle program, compared to a standard alcohol and drug abuse education, the Be A Winner program. Community-based participatory research was used to implement a two-condition, quasi-experimental study. The sample included 540 Native American youth ages 10-12 years old from three tribal areas in the United States. Data were collected at baseline, 6 and 12-months post-intervention for both the intervention and control groups using demographic, cultural identity, alcohol use, and drug use questionnaires. Regression models evaluated participants' improvement in decreasing alcohol and drug use and increasing cultural identity. Findings revealed that alcohol and drug use decreased more significantly among youth who participated in the Intertribal Talking Circle (ITC) intervention program than youth who participated in a standard alcohol and drug abuse education Be A Winner (BAW) program. Cultural identity also increased more significantly among participants who completed the Talking Circle intervention program. Native American youth ages 10-12 years old respond positively to a culturally based intervention for the reduction of alcohol and drug use. The findings highlight the importance of cultural values and identity and their significance in preventing and reducing alcohol and drug use among Native American youth.


Assuntos
Indígena Americano ou Nativo do Alasca , Transtornos Relacionados ao Uso de Substâncias , Criança , Humanos , Educação em Saúde , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Inquéritos e Questionários , Estados Unidos , Assistência à Saúde Culturalmente Competente
2.
Psychiatry Res Neuroimaging ; 335: 111712, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37660442

RESUMO

Research suggests that traditional cultural factors are protective against mental health conditions in American Indian (AI) populations. This study aims to determine if cognitive control is a neurocognitive mechanism of the protective role of spirituality in AI people with generalized anxiety disorder (GAD). Participants self-identified as AI (n = 52) and included individuals with GAD (n = 16) and without GAD (n = 36). Electroencephalography was collected during a stop-signal task to probe cognitive control using the P3 event-related potential. Higher levels of spirituality attenuated the processing efficiency disruption among individuals with GAD as indicated by P3 amplitudes closer to that of individuals without GAD.


Assuntos
Indígena Americano ou Nativo do Alasca , Transtornos de Ansiedade , Espiritualidade , Humanos , Transtornos de Ansiedade/psicologia , Cognição , Eletroencefalografia , Potenciais Evocados
3.
Toxins (Basel) ; 15(5)2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37235366

RESUMO

Some 14% of global prevalence, based on high-income country populations, suffers from migraine. Chronic migraine is very disabling, being characterized by at least 15 headache days per month of which at least 8 days present the features of migraine. Onabotulinumtoxin A, targeting the machinery for exocytosis of neurotransmitters and neuropeptides, has been approved for use in chronic migraine since 2010. This systematic review and meta-analysis appraises the safety of onabotulinumtoxin A treatment for chronic migraine and the occurrence of treatment-related adverse events (TRAEs) in randomized, clinical studies in comparison with placebo or other comparators and preventative treatments according to the most updated Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 recommendations. The search retrieved 888 total records. Nine studies are included and seven were eligible for meta-analysis. The present study demonstrates that toxin produces more TRAEs than placebo, but less than oral topiramate, supporting the safety of onabotulinumtoxin A, and highlights the heterogeneity of the studies present in the literature (I2 = 96%; p < 0.00001). This points to the need for further, adequately powered, randomized clinical trials assessing the safety of onabotulinumtoxin A in combination with the newest treatment options.


Assuntos
Toxinas Botulínicas Tipo A , Transtornos de Enxaqueca , Humanos , Toxinas Botulínicas Tipo A/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Transtornos de Enxaqueca/tratamento farmacológico , Cefaleia/tratamento farmacológico
4.
Int J Mol Sci ; 24(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36674850

RESUMO

The trafficking of transient receptor potential (TRP) channels to the plasma membrane and the release of calcitonin gene-related peptide (CGRP) from trigeminal ganglion neurons (TGNs) are implicated in some aspects of chronic migraines. These exocytotic processes are inhibited by cleavage of SNAREs with botulinum neurotoxins (BoNTs); moreover, type A toxin (/A) clinically reduces the frequency and severity of migraine attacks but not in all patients for unknown reasons. Herein, neonatal rat TGNs were stimulated with allyl isothiocyanate (AITC), a TRPA1 agonist, and dose relationships were established to link the resultant exocytosis of CGRP with Ca2+ influx. The CGRP release, quantified by ELISA, was best fit by a two-site model (EC50 of 6 and 93 µM) that correlates with elevations in intracellular Ca2+ [Ca2+]i revealed by time-lapse confocal microscopy of fluo-4-acetoxymethyl ester (Fluo-4 AM) loaded cells. These signals were all blocked by two TRPA1 antagonists, HC-030031 and A967079. At low [AITC], [Ca2+]i was limited because of desensitisation to the agonist but rose for concentrations > 0.1 mM due to a deduced non-desensitising second phase of Ca2+ influx. A recombinant BoNT chimera (/DA), which cleaves VAMP1/2/3, inhibited AITC-elicited CGRP release to a greater extent than SNAP-25-cleaving BoNT/A. /DA also proved more efficacious against CGRP efflux evoked by a TRPV1 agonist, capsaicin. Nerve growth factor (NGF), a pain-inducing sensitiser of TGNs, enhanced the CGRP exocytosis induced by low [AITC] only. Both toxins blocked NGF-induced neuropeptide secretion and its enhancement of the response to AITC. In conclusion, NGF sensitisation of sensory neurons involves TRPA1, elevated Ca2+ influx, and CGRP exocytosis, mediated by VAMP1/2/3 and SNAP-25 which can be attenuated by the BoNTs.


Assuntos
Toxinas Botulínicas , Canais de Potencial de Receptor Transitório , Ratos , Animais , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Proteína 1 Associada à Membrana da Vesícula/metabolismo , Fator de Crescimento Neural/farmacologia , Fator de Crescimento Neural/metabolismo , Toxinas Botulínicas/metabolismo , Células Receptoras Sensoriais/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Canal de Cátion TRPA1/metabolismo
5.
Toxins (Basel) ; 14(2)2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-35202143

RESUMO

Chimeras of botulinum neurotoxin (BoNT) serotype A (/A) combined with /E protease might possess improved analgesic properties relative to either parent, due to inheriting the sensory neurotropism of the former with more extensive disabling of SNAP-25 from the latter. Hence, fusions of /E protease light chain (LC) to whole BoNT/A (LC/E-BoNT/A), and of the LC plus translocation domain (HN) of /E with the neuronal acceptor binding moiety (HC) of /A (BoNT/EA), created previously by gene recombination and expression in E. coli., were used. LC/E-BoNT/A (75 units/kg) injected into the whisker pad of rats seemed devoid of systemic toxicity, as reflected by an absence of weight loss, but inhibited the nocifensive behavior (grooming, freezing, and reduced mobility) induced by activating TRPV1 with capsaicin, injected at various days thereafter. No sex-related differences were observed. c-Fos expression was increased five-fold in the trigeminal nucleus caudalis ipsi-lateral to capsaicin injection, relative to the contra-lateral side and vehicle-treated controls, and this increase was virtually prevented by LC/E-BoNT/A. In vitro, LC/E-BoNT/A or /EA diminished CGRP exocytosis from rat neonate trigeminal ganglionic neurons stimulated with up to 1 µM capsaicin, whereas BoNT/A only substantially reduced the release in response to 0.1 µM or less of the stimulant, in accordance with the /E protease being known to prevent fusion of exocytotic vesicles.


Assuntos
Analgésicos/farmacologia , Toxinas Botulínicas Tipo A/farmacologia , Capsaicina/farmacologia , Neurotoxinas/farmacologia , Células Receptoras Sensoriais/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Comportamento Animal/efeitos dos fármacos , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Feminino , Masculino , Dor/induzido quimicamente , Dor/tratamento farmacológico , Dor/metabolismo , Ratos Sprague-Dawley , Células Receptoras Sensoriais/metabolismo , Proteína 25 Associada a Sinaptossoma/metabolismo , Gânglio Trigeminal/citologia
6.
Int J Mol Sci ; 23(2)2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35055082

RESUMO

Nerve growth factor (NGF) is known to intensify pain in various ways, so perturbing pertinent effects without negating its essential influences on neuronal functions could help the search for much-needed analgesics. Towards this goal, cultured neurons from neonatal rat trigeminal ganglia-a locus for craniofacial sensory nerves-were used to examine how NGF affects the Ca2+-dependent release of a pain mediator, calcitonin gene-related peptide (CGRP), that is triggered by activating a key signal transducer, transient receptor potential vanilloid 1 (TRPV1) with capsaicin (CAP). Measurements utilised neurons fed with or deprived of NGF for 2 days. Acute re-introduction of NGF induced Ca2+-dependent CGRP exocytosis that was inhibited by botulinum neurotoxin type A (BoNT/A) or a chimera of/E and/A (/EA), which truncated SNAP-25 (synaptosomal-associated protein with Mr = 25 k) at distinct sites. NGF additionally caused a Ca2+-independent enhancement of the neuropeptide release evoked by low concentrations (<100 nM) of CAP, but only marginally increased the peak response to ≥100 nM. Notably, BoNT/A inhibited CGRP exocytosis evoked by low but not high CAP concentrations, whereas/EA effectively reduced responses up to 1 µM CAP and inhibited to a greater extent its enhancement by NGF. In addition to establishing that sensitisation of sensory neurons to CAP by NGF is dependent on SNARE-mediated membrane fusion, insights were gleaned into the differential ability of two regions in the C-terminus of SNAP-25 (181-197 and 198-206) to support CAP-evoked Ca2+-dependent exocytosis at different intensities of stimulation.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/biossíntese , Capsaicina/farmacologia , Fator de Crescimento Neural/metabolismo , Células Receptoras Sensoriais/efeitos dos fármacos , Células Receptoras Sensoriais/metabolismo , Gânglio Trigeminal/efeitos dos fármacos , Gânglio Trigeminal/metabolismo , Animais , Toxinas Botulínicas Tipo A/farmacologia , Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Relação Dose-Resposta a Droga , Exocitose/efeitos dos fármacos , Fator de Crescimento Neural/farmacologia , Proteólise , Ratos , Proteína 25 Associada a Sinaptossoma/metabolismo
7.
Plant Dis ; 106(8): 2228-2238, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34978874

RESUMO

Meta-analysis was used to compare yield protection and nematode suppression provided by two seed-applied and two soil-applied nematicides against Meloidogyne incognita and Rotylenchulus reniformis on cotton across 3 years and several trial locations in the U.S. Cotton Belt. Nematicides consisted of thiodicarb- and fluopyram-treated seed, aldicarb and fluopyram applied in furrow, and combinations of the seed treatments and soil-applied fluopyram. The nematicides had no effect on nematode reproduction or root infection but had a significant impact on seed cotton yield response ([Formula: see text]), with an average increase of 176 and 197 kg/ha relative to the nontreated control in M. incognita and R. reniformis infested fields, respectively. However, because of significant variation in yield protection and nematode suppression by nematicides, five or six moderator variables (cultivar resistance [M. incognita only], nematode infestation level, nematicide treatment, application method, trial location, and growing season) were used depending on nematode species. In M. incognita-infested fields, greater yield protection was observed with nematicides applied in furrow and with seed-applied + in-furrow than with solo seed-applied nematicide applications. Most notable of these in-furrow nematicides were aldicarb and fluopyram (>131 g/ha) with or without a seed-applied nematicide compared with thiodicarb. In R. reniformis-infested fields, moderator variables provided no further explanation of the variation in yield response produced by nematicides. Furthermore, moderator variables provided little explanation of the variation in nematode suppression by nematicides in M. incognita- and R. reniformis-infested fields. The limited explanation by the moderator variables on the field efficacy of nematicides in M. incognita- and R. reniformis-infested fields demonstrates the difficulty of managing these pathogens with nonfumigant nematicides across the U.S. Cotton Belt.


Assuntos
Antinematódeos , Tylenchoidea , Aldicarb/toxicidade , Animais , Antinematódeos/toxicidade , Benzamidas/toxicidade , Gossypium , Piridinas/toxicidade , Sementes , Solo , Tylenchoidea/efeitos dos fármacos , Tylenchoidea/fisiologia , Estados Unidos
8.
Cell Physiol Biochem ; 55(4): 428-448, 2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34242501

RESUMO

BACKGROUND/AIMS: Nociceptors detect noxious capsaicin (CAPS) via the transient receptor potential vanilloid 1 (TRPV1) ion channel, but coding mechanisms for relaying CAPS concentration [CAPS] remain obscure. Prolonged (up to 1h.) exposure to CAPS is used clinically to desensitise sensory fibres for treatment of neuropathic pain, but its signalling has typically been studied in cultures of dissociated sensory neurons employing low cell numbers and very short exposure times. Thus, it was pertinent to examine responses to longer CAPS exposures in large populations of adult neurons. METHODS: Confocal fluorescence microscopy was used to monitor the simultaneous excitation by CAPS of neuronal populations in intact L3/4 dorsal root ganglia (DRG) explants from adult pirt-GCaMP3 mice that express a cytoplasmic, genetically-encoded Ca2+ sensor in almost all primary sensory neurons. Peak analysis was performed using GraphPad Prism 9 to deconstruct the heterogenous and complex fluorescence signals observed into informative, readily-comparable measurements: number of signals, their lag time, maximum intensity relative to baseline (Max.) and duration. RESULTS: Exposure for 5 min. to CAPS activated plasmalemmal TRPV1 and led to increased fluorescence due to Ca2+ entry into DRG neurons (DRGNs), as it was prevented by capsazepine or removal of extracellular Ca2+. Increasing [CAPS] (0.3, 1 and 10 µM, respectively) evoked signals from more neurons (123, 275 and 390 from 5 DRG) with shorter average lag (6.4 ± 0.4, 3.3 ± 0.2 and 1.9 ± 0.1 min.) and longer duration (1.4 ± 0.2, 2.9 ± 0.2 and 4.8 ± 0.3 min.). Whilst raising [CAPS] produced a modest augmentation of Max. for individual neurons, those with large increases were selectively expedited; this contributed to a faster onset and higher peak of cumulative fluorescence for an enlarged responding neuronal population. CAPS caused many cells to fluctuate between high and low levels of fluorescence, with consecutive pulses increasing Max. and duration especially when exposure was extended from 5 to 20 min. Such signal facilitation counteracted tachyphylaxis, observed upon repeated exposure to 1 µM CAPS, preserving the cumulative fluorescence over time (signal density) in the population. CONCLUSION: Individual neurons within DRG differed extensively in the dynamics of response to CAPS, but systematic changes elicited by elevating [CAPS] increased signal density in a graded manner, unveiling a possible mechanism for population coding of responses to noxious chemicals. Signal density is sustained during prolonged and repeated exposure to CAPS, despite profound tachyphylaxis in some neurons, by signal facilitation in others. This may explain the burning sensation that persists for several hours when CAPS is used clinically.


Assuntos
Cálcio/metabolismo , Capsaicina/farmacologia , Gânglios Espinais/metabolismo , Nociceptores/metabolismo , Transdução de Sinais/efeitos dos fármacos , Canais de Cátion TRPV/metabolismo , Animais , Feminino , Gânglios Espinais/citologia , Masculino , Camundongos , Camundongos Transgênicos , Nociceptores/citologia , Transdução de Sinais/genética , Canais de Cátion TRPV/genética
9.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806699

RESUMO

Nociceptors sense hazards via plasmalemmal cation channels, including transient receptor potential vanilloid 1 (TRPV1). Nerve growth factor (NGF) sensitises TRPV1 to capsaicin (CAPS), modulates nociceptor excitability and induces thermal hyperalgesia, but cellular mechanisms remain unclear. Confocal microscopy was used to image changes in intracellular Ca2+ concentration ([Ca2+]i) across neuronal populations in dorsal root ganglia (DRG) explants from pirt-GCaMP3 adult mice, which express a fluorescent reporter in their sensory neurons. Raised [Ca2+]i was detected in 84 neurons of three DRG explants exposed to NGF (100 ng/mL) and most (96%) of these were also excited by 1 µM CAPS. NGF elevated [Ca2+]i in about one-third of the neurons stimulated by 1 µM CAPS, whether applied before or after the latter. In neurons excitable by NGF, CAPS-evoked [Ca2+]i signals appeared significantly sooner (e.g., respective lags of 1.0 ± 0.1 and 1.9 ± 0.1 min), were much (>30%) brighter and lasted longer (6.6 ± 0.4 vs. 3.9 ± 0.2 min) relative to those non-responsive to the neurotrophin. CAPS tachyphylaxis lowered signal intensity by ~60% but was largely prevented by NGF. Increasing CAPS from 1 to 10 µM nearly doubled the number of cells activated but only modestly increased the amount co-activated by NGF. In conclusion, a sub-population of the CAPS-sensitive neurons in adult mouse DRG that can be excited by NGF is more sensitive to CAPS, responds with stronger signals and is further sensitised by transient exposure to the neurotrophin.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Capsaicina/farmacologia , Gânglios Espinais/efeitos dos fármacos , Fator de Crescimento Neural/farmacologia , Neurônios/efeitos dos fármacos , Nociceptividade/efeitos dos fármacos , Animais , Feminino , Gânglios Espinais/metabolismo , Hiperalgesia/metabolismo , Masculino , Camundongos , Fatores de Crescimento Neural/metabolismo , Neurônios/metabolismo , Nociceptores/metabolismo , Transdução de Sinais/efeitos dos fármacos , Canais de Cátion TRPV/metabolismo
10.
Health Promot Pract ; 22(6): 778-785, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-32406286

RESUMO

Background. Substance use among American Indians (AIs) is a critical health issue and accounts for many health problems such as chronic liver disease, cirrhosis, behavioral health conditions, homicide, suicide, and motor vehicle accidents. In 2013, the highest rates of substance use and dependence were seen among AIs when compared to all other population groups, although these rates vary across different tribes. Among AI adolescents, high rates of substance use have been associated with environmental and historical factors, including poverty, historical trauma, bicultural stress, and changing tribal/familial roles. Our project, the Intertribal Talking Circle intervention, involved adapting, tailoring, implementing, and evaluating an existing intervention for AI youth of three tribal communities in the United States. Formative Results. Community partnership committees (CPCs) identified alcohol, marijuana, and prescription medications as high priority substances. CPC concerns focused on the increasing substance use in their communities and the corresponding negative impacts on families, stating a lack of coping skills, positive role models, and hope for the future as concerns for youth. Cultural Tailoring Process Results. Each site formed a CPC that culturally tailored the intervention for their tribal community. This included translating Keetoowah-Cherokee language, cultural practices, and symbolism into the local tribal customs for relevance. The CPCs were essential for incorporating local context and perceived concerns around AI adolescent substance use. These results may be helpful to other tribal communities developing/implementing substance use prevention interventions for AI youth. It is critical that Indigenous cultures and local context be factored into such programs.


Assuntos
Indígenas Norte-Americanos , Transtornos Relacionados ao Uso de Substâncias , Suicídio , Adolescente , Cultura , Humanos , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Estados Unidos , Indígena Americano ou Nativo do Alasca
11.
Front Plant Sci ; 11: 564495, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33262774

RESUMO

The conserved oligomeric Golgi (COG) complex, functioning in retrograde trafficking, is a universal structure present among eukaryotes that maintains the correct Golgi structure and function. The COG complex is composed of eight subunits coalescing into two sub-complexes. COGs1-4 compose Sub-complex A. COGs5-8 compose Sub-complex B. The observation that COG interacts with the syntaxins, suppressors of the erd2-deletion 5 (Sed5p), is noteworthy because Sed5p also interacts with Sec17p [alpha soluble NSF attachment protein (α-SNAP)]. The α-SNAP gene is located within the major Heterodera glycines [soybean cyst nematode (SCN)] resistance locus (rhg1) and functions in resistance. The study presented here provides a functional analysis of the Glycine max COG complex. The analysis has identified two paralogs of each COG gene. Functional transgenic studies demonstrate at least one paralog of each COG gene family functions in G. max during H. glycines resistance. Furthermore, treatment of G. max with the bacterial effector harpin, known to function in effector triggered immunity (ETI), leads to the induced transcription of at least one member of each COG gene family that has a role in H. glycines resistance. In some instances, altered COG gene expression changes the relative transcript abundance of syntaxin 31. These results indicate that the G. max COG complex functions through processes involving ETI leading to H. glycines resistance.

12.
Prev Sci ; 21(Suppl 1): 54-64, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30397737

RESUMO

Given the paucity of empirically based health promotion interventions designed by and for American Indian, Alaska Native, and Native Hawaiian (i.e., Native) communities, researchers and partnering communities have had to rely on the adaptation of evidence-based interventions (EBIs) designed for non-Native populations, a decidedly sub-optimal approach. Native communities have called for development of Indigenous health promotion programs in which their cultural worldviews and protocols are prioritized in the design, development, testing, and implementation. There is limited information regarding how Native communities and scholars have successfully collaborated to design and implement culturally based prevention efforts "from the ground up." Drawing on five diverse community-based Native health intervention studies, we describe strategies for designing and implementing culturally grounded models of health promotion developed in partnership with Native communities. Additionally, we highlight indigenist worldviews and protocols that undergird Native health interventions with an emphasis on the incorporation of (1) original instructions, (2) relational restoration, (3) narrative-[em]bodied transformation, and (4) indigenist community-based participatory research (ICBPR) processes. Finally, we demonstrate how culturally grounded interventions can improve population health when they prioritize local Indigenous knowledge and health-positive messages for individual to multi-level community interventions.


Assuntos
Competência Cultural , Promoção da Saúde/métodos , Indígenas Norte-Americanos , Havaiano Nativo ou Outro Ilhéu do Pacífico , Desenvolvimento de Programas/métodos , Feminino , Equidade em Saúde , Humanos , Masculino , Estados Unidos
13.
Plant Physiol Biochem ; 137: 25-41, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30711881

RESUMO

Mitogen activated protein kinases (MAPKs) play important signal transduction roles. However, little is known regarding how they influence the gene expression of other family members and the relationship to a biological process, including the Glycine max defense response to Heterodera glycines. Transcriptomics have identified MAPK gene expression occurring within root cells undergoing a defense response to a pathogenic event initiated by H. glycines in the allotetraploid Glycine max. Functional analyses are presented for its 32 MAPKs revealing 9 have a defense role, including homologs of Arabidopsis thaliana MAPK (MPK) MPK2, MPK3, MPK4, MPK5, MPK6, MPK13, MPK16 and MPK20. Defense signaling occurring through pathogen activated molecular pattern (PAMP) triggered immunity (PTI) and effector triggered immunity (ETI) have been determined in relation to these MAPKs. Five different types of gene expression relate to MAPK expression, influencing PTI and ETI gene expression and proven defense genes including an ABC-G transporter, 20S membrane fusion particle components, glycoside biosynthesis, carbon metabolism, hemicellulose modification, transcription and secretion. The experiments show MAPKs broadly influence defense MAPK gene expression, including the co-regulation of parologous MAPKs and reveal its relationship to proven defense genes. The experiments reveal each defense MAPK induces the expression of a G. max homolog of a PATHOGENESIS RELATED1 (PR1), itself shown to function in defense in the studied pathosystem.


Assuntos
Glycine max/parasitologia , Interações Hospedeiro-Parasita/fisiologia , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas de Plantas/genética , Tylenchoidea/patogenicidade , Animais , Regulação da Expressão Gênica de Plantas , Sistema de Sinalização das MAP Quinases , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Família Multigênica , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/parasitologia , Plantas Geneticamente Modificadas , Interferência de RNA , Glycine max/fisiologia
14.
Plant Physiol Biochem ; 129: 331-348, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29936240

RESUMO

Soybean (Glycine max) infection by the charcoal rot (CR) ascomycete Macrophomina phaseolina is enhanced by the soybean cyst nematode (SCN) Heterodera glycines. We hypothesized that G. max genetic lines impairing infection by M. phaseolina would also limit H. glycines parasitism, leading to resistance. As a part of this M. phaseolina resistance process, the genetic line would express defense genes already proven to impair nematode parasitism. Using G. max[DT97-4290/PI 642055], exhibiting partial resistance to M. phaseolina, experiments show the genetic line also impairs H. glycines parasitism. Furthermore, comparative studies show G. max[DT97-4290/PI 642055] exhibits induced expression of the effector triggered immunity (ETI) gene NON-RACE SPECIFIC DISEASE RESISTANCE 1/HARPIN INDUCED1 (NDR1/HIN1) that functions in defense to H. glycines as compared to the H. glycines and M. phaseolina susceptible line G. max[Williams 82/PI 518671]. Other defense genes that are induced in G. max[DT97-4290/PI 642055] include the pathogen associated molecular pattern (PAMP) triggered immunity (PTI) genes ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1), NONEXPRESSOR OF PR1 (NPR1) and TGA2. These observations link G. max defense processes that impede H. glycines parasitism to also potentially function toward impairing M. phaseolina pathogenicity. Testing this hypothesis, G. max[Williams 82/PI 518671] genetically engineered to experimentally induce GmNDR1-1, EDS1-2, NPR1-2 and TGA2-1 expression leads to impaired M. phaseolina pathogenicity. In contrast, G. max[DT97-4290/PI 642055] engineered to experimentally suppress the expression of GmNDR1-1, EDS1-2, NPR1-2 and TGA2-1 by RNA interference (RNAi) enhances M. phaseolina pathogenicity. The results show components of PTI and ETI impair both nematode and M. phaseolina pathogenicity.


Assuntos
Ascomicetos , Resistência à Doença/genética , Glycine max/microbiologia , Doenças das Plantas/microbiologia , Animais , Expressão Gênica , Genes de Plantas/genética , Genes de Plantas/fisiologia , Nematoides , Doenças das Plantas/imunologia , Doenças das Plantas/parasitologia , Raízes de Plantas/microbiologia , Caules de Planta/microbiologia , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase , Glycine max/genética , Glycine max/imunologia , Glycine max/parasitologia
15.
Plant Physiol Biochem ; 121: 161-175, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29107936

RESUMO

The bacterial effector harpin induces the transcription of the Arabidopsis thaliana NON-RACE SPECIFIC DISEASE RESISTANCE 1/HARPIN INDUCED1 (NDR1/HIN1) coiled-coil nucleotide binding leucine rich repeat (CC-NB-LRR) defense signaling gene. In Glycine max, Gm-NDR1-1 transcripts have been detected within root cells undergoing a natural resistant reaction to parasitism by the syncytium-forming nematode Heterodera glycines, functioning in the defense response. Expressing Gm-NDR1-1 in Gossypium hirsutum leads to resistance to Meloidogyne incognita parasitism. In experiments presented here, the heterologous expression of Gm-NDR1-1 in G. hirsutum impairs Rotylenchulus reniformis parasitism. These results are consistent with the hypothesis that Gm-NDR1-1 expression functions broadly in generating a defense response. To examine a possible relationship with harpin, G. max plants topically treated with harpin result in induction of the transcription of Gm-NDR1-1. The result indicates the topical treatment of plants with harpin, itself, may lead to impaired nematode parasitism. Topical harpin treatments are shown to impair G. max parasitism by H. glycines, M. incognita and R. reniformis and G. hirsutum parasitism by M. incognita and R. reniformis. How harpin could function in defense has been examined in experiments showing it also induces transcription of G. max homologs of the proven defense genes ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1), TGA2, galactinol synthase, reticuline oxidase, xyloglucan endotransglycosylase/hydrolase, alpha soluble N-ethylmaleimide-sensitive fusion protein (α-SNAP) and serine hydroxymethyltransferase (SHMT). In contrast, other defense genes are not directly transcriptionally activated by harpin. The results indicate harpin induces pathogen associated molecular pattern (PAMP) triggered immunity (PTI) and effector-triggered immunity (ETI) defense processes in the root, activating defense to parasitic nematodes.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Gossypium , Nematoides , Doenças das Plantas , Transdução de Sinais , Animais , Arabidopsis/genética , Arabidopsis/imunologia , Arabidopsis/parasitologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/imunologia , Gossypium/genética , Gossypium/imunologia , Gossypium/parasitologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Doenças das Plantas/parasitologia , Transdução de Sinais/genética , Transdução de Sinais/imunologia
16.
Bioconjug Chem ; 28(6): 1684-1692, 2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-28489355

RESUMO

Numerous naturally occurring toxins can perturb biological systems when they invade susceptible cells. Coupling of pertinent targeting ligands to the active domains of such proteins provides a strategy for directing these to particular cellular populations implicated in disease. A novel approach described herein involved fusion of one mutated immunoglobulin G (IgG) binding moiety of staphylococcal protein A to the SNARE protease and translocation domain of botulinum neurotoxin A (BoNT/A). This chimera could be monovalently coupled to IgG or via its Fc region to recombinant targeting ligands. The utility of the resulting conjugates is demonstrated by the delivery of a SNARE protease into a cell line expressing tropomyosin receptor kinase A (TrkA) through coupling to anti-TrkA IgG or a fusion of Fc and nerve-growth factor. Thus, this is a versitile and innovative technology for conjugating toxins to diverse ligands for retargeted cell delivery of potential therapeutics.


Assuntos
Toxinas Botulínicas Tipo A/química , Imunoglobulina G/química , Proteínas SNARE/metabolismo , Sítios de Ligação , Sistemas de Liberação de Medicamentos , Fragmentos Fc das Imunoglobulinas , Imunoglobulina G/metabolismo , Fator de Crescimento Neural/imunologia , Receptor trkA/imunologia , Vacinas
17.
Plant Physiol Biochem ; 114: 60-71, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28273511

RESUMO

A Glycine max homolog of the Arabidopsis thaliana NON-RACE SPECIFIC DISEASE RESISTANCE 1 (NDR1) coiled-coil nucleotide binding leucine rich repeat (CC-NB-LRR) defense signaling gene (Gm-NDR1-1) is expressed in root cells undergoing a defense response to the root pathogenic nematode, Heterodera glycines. Gm-NDR1-1 overexpression in the H. glycines-susceptible genotype G. max[Williams 82/PI 518671] impairs parasitism. In contrast, Gm-NDR1-1 RNA interference (RNAi) in the H. glycines-resistant genotype G. max[Peking/PI 548402] facilitates parasitism. The broad effectiveness of Gm-NDR1-1 in impairing parasitism has then been examined by engineering its heterologous expression in Gossypium hirsutum which is susceptible to the root pathogenic nematode Meloidogyne incognita. The heterologous expression of Gm-NDR1-1 in G. hirsutum effectively impairs M. incognita parasitism, reducing gall, egg mass, egg and juvenile numbers. In contrast to our prior experiments examining the effectiveness of the heterologous expression of a G. max homolog of the A. thaliana salicyclic acid signaling (SA) gene NONEXPRESSOR OF PR1 (Gm-NPR1-2), no cumulative negative effect on M. incognita parasitism has been observed in G. hirsutum expressing Gm-NDR1-1. The results indicate a common genetic basis exists for plant resistance to parasitic nematodes that involves Gm-NDR1. However, the Gm-NDR1-1 functions in ways that are measurably dissimilar to Gm-NPR1-2. Notably, Gm-NDR1-1 overexpression leads to increased relative transcript levels of its homologs of A. thaliana genes functioning in SA signaling, including NPR1-2, TGA2-1 and LESION SIMULATING DISEASE1 (LSD1-2) that is lost in Gm-NDR1-1 RNAi lines. Similar observations have been made regarding the expression of other defense genes.


Assuntos
Glycine max/genética , Glycine max/parasitologia , Proteínas de Plantas/genética , Animais , Proteínas de Arabidopsis/genética , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Gossypium/parasitologia , Interações Hospedeiro-Parasita , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/parasitologia , Plantas Geneticamente Modificadas , Glycine max/fisiologia , Fatores de Transcrição/genética , Tylenchoidea/patogenicidade
18.
Plant Dis ; 101(5): 774-784, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-30678579

RESUMO

In the past decade, increased attention has been placed on biological control of plant-parasitic nematodes using various fungi and bacteria. The objectives of this study were to evaluate the potential of 662 plant growth-promoting rhizobacteria (PGPR) strains for mortality to Meloidogyne incognita J2 in vitro and for nematode management in greenhouse, microplot, and field trials. Results indicated that the mortality of M. incognita J2 by the PGPR strains ranged from 0 to 100% with an average of 39%. Among the PGPR strains examined, 212 of 662 strains (or 33%) caused significantly greater mortality percent of M. incognita J2 than the untreated control. Bacillus was the major genus initiating a greater mortality percentage when compared with the other genera. In subsequent trials, B. velezensis strain Bve2 reduced M. incognita eggs per gram of cotton root in the greenhouse trials at 45 days after planting (DAP) similarly to the commercial standards Abamectin and Clothianidin plus B. firmus I-1582. Bacillus mojavensis strain Bmo3, B. velezensis strain Bve2, B. subtilis subsp. subtilis strain Bsssu3, and the Mixture 2 (Abamectin + Bve2 + B. altitudinis strain Bal13) suppressed M. incognita eggs per gram of root in the microplot at 45 DAP. Bacillus velezensis strains Bve2 and Bve12 also increased seed-cotton yield in the microplot and field trials. Overall, results indicate that B. velezensis strains Bve2 and Bve12, B. mojavensis strain Bmo3, and Mixture 2 have potential to reduce M. incognita population density and to enhance growth of cotton when applied as in-furrow sprays at planting.

19.
Plant Signal Behav ; 12(2): e1274481, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28010187

RESUMO

The term regulon has been coined in the genetic model plant Arabidopsis thaliana, denoting a structural and physiological defense apparatus defined genetically through the identification of the penetration (pen) mutants. The regulon is composed partially by the soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) syntaxin PEN1. PEN1 has homology to a Saccharomyces cerevisae gene that regulates a Secretion (Sec) protein, Suppressor of Sec 1 (Sso1p). The regulon is also composed of the ß-glucosidase (PEN2) and an ATP binding cassette (ABC) transporter (PEN3). While important in inhibiting pathogen infection, limited observations have been made regarding the transcriptional regulation of regulon genes until now. Experiments made using the model agricultural Glycine max (soybean) have identified co-regulated gene expression of regulon components. The results explain the observation of hundreds of genes expressed specifically in the root cells undergoing the natural process of defense. Data regarding additional G. max genes functioning within the context of the regulon are presented here, including Sec 14, Sec 4 and Sec 23. Other examined G. max homologs of membrane fusion genes include an endosomal bromo domain-containing protein1 (Bro1), syntaxin6 (SYP6), SYP131, SYP71, SYP8, Bet1, coatomer epsilon (ϵ-COP), a coatomer zeta (ζ-COP) paralog and an ER to Golgi component (ERGIC) protein. Furthermore, the effectiveness of biochemical pathways that would function within the context of the regulon ave been examined, including xyloglucan xylosyltransferase (XXT), reticuline oxidase (RO) and galactinol synthase (GS). The experiments have unveiled the importance of the regulon during defense in the root and show how the deposition of callose relates to the process.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Galactosiltransferases/genética , Galactosiltransferases/metabolismo , Glucanos/metabolismo , N-Glicosil Hidrolases/genética , N-Glicosil Hidrolases/metabolismo , Oxirredutases N-Desmetilantes/genética , Oxirredutases N-Desmetilantes/metabolismo , Pentosiltransferases/genética , Pentosiltransferases/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Regulon/genética , Proteínas SNARE/genética , Proteínas SNARE/metabolismo , Glycine max/genética , Glycine max/metabolismo , beta-Glucosidase/genética , beta-Glucosidase/metabolismo
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