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1.
Phytopathology ; 114(7): 1626-1636, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38489164

RESUMEN

Development of durable resistance effective against a broad range of pathotypes is crucial for restoration of pathogen-damaged ecosystems. This study dissected the complex genetic architecture for limber pine quantitative disease resistance (QDR) to Cronartium ribicola using a genome-wide association study. Eighteen-month-old seedlings were inoculated for resistance screening under controlled conditions. Disease development was quantitatively assessed for QDR-related traits over 4 years postinoculation. To reveal the genomic architecture contributing to QDR-related traits, a set of genes related to disease resistance with genome-wide distribution was selected for targeted sequencing for genotyping of single-nucleotide polymorphisms (SNPs). The genome-wide association study revealed a set of SNPs significantly associated with quantitative traits for limber pine QDR to white pine blister rust, including number of needle spots and stem cankers, as well as survival 4 years postinoculation. The peaks of marker-trait associations displayed a polygenic pattern, with genomic regions as potential resistant quantitative trait loci, distributed over 10 of the 12 linkage groups (LGs) of Pinus. None of them was linked to the Cr4-controlled major gene resistance previously mapped on LG08. Both normal canker and bole infection were mapped on LG05, and the associated SNPs explained their phenotypic variance up to 52%, tagging a major resistant quantitative trait locus. Candidate genes containing phenotypically associated SNPs encoded putative nucleotide-binding site leucine-rich repeat proteins, leucine-rich repeat-receptor-like kinase, cytochrome P450 superfamily protein, heat shock cognate protein 70, glutamate receptor, RNA-binding family protein, and unknown protein. The confirmation of resistant quantitative trait loci broadens the genetic pool of limber pine resistance germplasm for resistance breeding.


Asunto(s)
Basidiomycota , Resistencia a la Enfermedad , Estudio de Asociación del Genoma Completo , Pinus , Enfermedades de las Plantas , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/genética , Resistencia a la Enfermedad/genética , Pinus/genética , Pinus/microbiología , Pinus/inmunología , Polimorfismo de Nucleótido Simple/genética , Basidiomycota/fisiología , Sitios de Carácter Cuantitativo/genética , Fenotipo , Genotipo , Herencia Multifactorial/genética
2.
J Chem Educ ; 100(4): 1511-1522, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37067867

RESUMEN

This paper introduces hands-on curricular modules integrated with research in atmospheric ice nucleation, which is an important phenomenon potentially influencing global climate change. The primary goal of this work is to promote meaningful laboratory exercises to enhance the competence of students in the fields of science, technology, engineering, and math (STEM) by applying an appropriate methodology to laboratory ice nucleation measurements. To achieve this goal, three laboratory modules were developed with 18 STEM interns and tested by 28 students in a classroom setting. Students were trained to experimentally simulate atmospheric ice nucleation and cloud droplet freezing. For practical training, this work utilized a simple freezing assay device called the West Texas Cryogenic Refrigerator Applied to Freezing Test (WT-CRAFT) system. More specifically, students were provided with hands-on lessons to calibrate WT-CRAFT with deionized water and apply analytical techniques to understand the physicochemical properties of bulk water and droplet freezing. All procedures to implement the developed modules were typewritten during this process, and shareable read-ahead exploration materials were developed and compiled as a curricular product. Additionally, students conducted complementary analyses to identify possible catalysts of heterogeneous freezing in the water. The water analyses included: pH, conductivity, surface tension, and electron microscopy-energy-dispersive X-ray spectroscopy. During the data and image analysis process, students learned how to analyze droplet freezing spectra as a function of temperature, screen and interpret the data, perform uncertainty analyses, and estimate ice nucleation efficiency using computer programs. Based on the formal program assessment of learning outcomes and direct (yet deidentified) student feedback, we broadly achieved our goals to (1) improve their problem-solving skills by combining multidisciplinary science and math skills and (2) disseminate data and results with variability and uncertainty. The developed modules can be applied at any institute to advance undergraduate and graduate curricula in environmental science.

3.
Circ Res ; 126(1): 41-56, 2020 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-31656131

RESUMEN

RATIONALE: The mitochondrial Poldip2 (protein polymerase interacting protein 2) is required for the activity of the tricarboxylic acid cycle. As a consequence, Poldip2 deficiency induces metabolic reprograming with repressed mitochondrial respiration and increased glycolytic activity. Though homozygous deletion of Poldip2 is lethal, heterozygous mice are viable and show protection against aneurysm and injury-induced neointimal hyperplasia, diseases linked to loss of vascular smooth muscle differentiation. Thus, we hypothesize that the metabolic reprograming induced by Poldip2 deficiency controls VSMC differentiation. OBJECTIVE: To determine the role of Poldip2-mediated metabolic reprograming in phenotypic modulation of VSMC. METHODS AND RESULTS: We show that Poldip2 deficiency in vascular smooth muscle in vitro and in vivo induces the expression of the SRF (serum response factor), myocardin, and MRTFA (myocardin-related transcription factor A) and dramatically represses KLF4 (Krüppel-like factor 4). Consequently, Poldip2-deficient VSMC and mouse aorta express high levels of contractile proteins and, more significantly, these cells do not dedifferentiate nor acquire macrophage-like characteristics when exposed to cholesterol or PDGF (platelet-derived growth factor). Regarding the mechanism, we found that Poldip2 deficiency upregulates the hexosamine biosynthetic pathway and OGT (O-linked N-acetylglucosamine transferase)-mediated protein O-GlcNAcylation. Increased protein glycosylation causes the inhibition of a nuclear ubiquitin proteasome system responsible for SRF stabilization and KLF4 repression and is required for the establishment of the differentiated phenotype in Poldip2-deficient cells. CONCLUSIONS: Our data show that Poldip2 deficiency induces a highly differentiated phenotype in VSMCs through a mechanism that involves regulation of metabolism and proteostasis. Additionally, our study positions mitochondria-initiated signaling as key element of the VSMC differentiation programs that can be targeted to modulate VSMC phenotype during vascular diseases.


Asunto(s)
Proteínas Mitocondriales/fisiología , Músculo Liso Vascular/citología , Miocitos del Músculo Liso/metabolismo , Proteínas Nucleares/fisiología , Animales , Diferenciación Celular , Células Cultivadas , Regulación de la Expresión Génica , Humanos , Hiperplasia , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/biosíntesis , Factores de Transcripción de Tipo Kruppel/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias/metabolismo , Proteínas Mitocondriales/deficiencia , Proteínas Mitocondriales/genética , Miocitos del Músculo Liso/citología , Neointima , Proteínas Nucleares/biosíntesis , Proteínas Nucleares/deficiencia , Proteínas Nucleares/genética , Fenotipo , Complejo de la Endopetidasa Proteasomal/metabolismo , Factor de Respuesta Sérica/biosíntesis , Factor de Respuesta Sérica/genética , Transactivadores/biosíntesis , Transactivadores/genética , Ubiquitina/metabolismo
4.
Phytopathology ; 112(5): 1093-1102, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34732078

RESUMEN

All native North American white pines are highly susceptible to white pine blister rust (WPBR) caused by Cronartium ribicola. Understanding genomic diversity and molecular mechanisms underlying genetic resistance to WPBR remains one of the great challenges in improvement of white pines. To compare major gene resistance (MGR) present in two species, southwestern white pine (Pinus strobiformis) Cr3 and limber pine (P. flexilis) Cr4, we performed association analyses of Cr3-controlled resistant traits using single nucleotide polymorphism (SNP) assays designed with Cr4-linked polymorphic genes. We found that ∼70% of P. flexilis SNPs were transferable to P. strobiformis. Furthermore, several Cr4-linked SNPs were significantly associated with the Cr3-controlled traits in P. strobiformis families. The most significantly associated SNP (M326511_1126R) almost colocalized with Cr4 on the Pinus consensus linkage group 8, suggesting that Cr3 and Cr4 might be the same R locus, or have localizations very close to each other in the syntenic region of the P. strobiformis and P. flexilis genomes. M326511_1126R was identified as a nonsynonymous SNP, causing amino acid change (Val376Ile) in a putative pectin acetylesterase, with coding sequences identical between the two species. Moreover, top Cr3-associated SNPs were further developed as TaqMan genotyping assays, suggesting their usefulness as marker-assisted selection (MAS) tools to distinguish genotypes between quantitative resistance and MGR. This work demonstrates the successful transferability of SNP markers between two closely related white pine species in the hybrid zone, and the possibility for deployment of MAS tools to facilitate long-term WPBR management in P. strobiformis breeding and conservation.


Asunto(s)
Resistencia a la Enfermedad , Pinus , Enfermedades de las Plantas , Basidiomycota/patogenicidad , Resistencia a la Enfermedad/genética , Pinus/genética , Pinus/microbiología , Fitomejoramiento , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología
5.
BMC Genomics ; 22(1): 567, 2021 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-34294045

RESUMEN

BACKGROUND: Proteins with nucleotide binding site (NBS) and leucine-rich repeat (LRR) domains (NLR) make up one of most important resistance (R) families for plants to resist attacks from various pathogens and pests. The available transcriptomes of limber pine (Pinus flexilis) allow us to characterize NLR genes and related resistance gene analogs (RGAs) in host resistance against Cronartium ribicola, the causal fungal pathogen of white pine blister rust (WPBR) on five-needle pines throughout the world. We previously mapped a limber pine major gene locus (Cr4) that confers complete resistance to C. ribicola on the Pinus consensus linkage group 8 (LG-8). However, genetic distribution of NLR genes as well as their divergence between resistant and susceptible alleles are still unknown. RESULTS: To identify NLR genes at the Cr4 locus, the present study re-sequenced a total of 480 RGAs using targeted sequencing in a Cr4-segregated seed family. Following a call of single nucleotide polymorphisms (SNPs) and genetic mapping, a total of 541 SNPs from 155 genes were mapped across 12 LGs. Three putative NLR genes were newly mapped in the Cr4 region, including one that co-segregated with Cr4. The tight linkage of NLRs with Cr4-controlled phenotypes was further confirmed by bulked segregation analysis (BSA) using extreme-phenotype genome-wide association study (XP-GWAS) for significance test. Local tandem duplication in the Cr4 region was further supported by syntenic analysis using the sugar pine genome sequence. Significant gene divergences have been observed in the NLR family, revealing that diversifying selection pressures are relatively higher in local duplicated genes. Most genes showed similar expression patterns at low levels, but some were affected by genetic background related to disease resistance. Evidence from fine genetic dissection, evolutionary analysis, and expression profiling suggests that two NLR genes are the most promising candidates for Cr4 against WPBR. CONCLUSION: This study provides fundamental insights into genetic architecture of the Cr4 locus as well as a set of NLR variants for marker-assisted selection in limber pine breeding. Novel NLR genes were identified at the Cr4 locus and the Cr4 candidates will aid deployment of this R gene in combination with other major/minor genes in the limber pine breeding program.


Asunto(s)
Estudio de Asociación del Genoma Completo , Pinus , Basidiomycota , Disección , Humanos , Pinus/genética , Fitomejoramiento , Enfermedades de las Plantas/genética
6.
Proc Natl Acad Sci U S A ; 115(8): 1789-1794, 2018 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-29434038

RESUMEN

Although the addition of the prosthetic group lipoate is essential to the activity of critical mitochondrial catabolic enzymes, its regulation is unknown. Here, we show that lipoylation of the pyruvate dehydrogenase and α-ketoglutarate dehydrogenase (αKDH) complexes is a dynamically regulated process that is inhibited under hypoxia and in cancer cells to restrain mitochondrial respiration. Mechanistically, we found that the polymerase-δ interacting protein 2 (Poldip2), a nuclear-encoded mitochondrial protein of unknown function, controls the lipoylation of the pyruvate and α-KDH dihydrolipoamide acetyltransferase subunits by a mechanism that involves regulation of the caseinolytic peptidase (Clp)-protease complex and degradation of the lipoate-activating enzyme Ac-CoA synthetase medium-chain family member 1 (ACSM1). ACSM1 is required for the utilization of lipoic acid derived from a salvage pathway, an unacknowledged lipoylation mechanism. In Poldip2-deficient cells, reduced lipoylation represses mitochondrial function and induces the stabilization of hypoxia-inducible factor 1α (HIF-1α) by loss of substrate inhibition of prolyl-4-hydroxylases (PHDs). HIF-1α-mediated retrograde signaling results in a metabolic reprogramming that resembles hypoxic and cancer cell adaptation. Indeed, we observe that Poldip2 expression is down-regulated by hypoxia in a variety of cell types and basally repressed in triple-negative cancer cells, leading to inhibition of lipoylation of the pyruvate and α-KDH complexes and mitochondrial dysfunction. Increasing mitochondrial lipoylation by forced expression of Poldip2 increases respiration and reduces the growth rate of cancer cells. Our work unveils a regulatory mechanism of catabolic enzymes required for metabolic plasticity and highlights the role of Poldip2 as key during hypoxia and cancer cell metabolic adaptation.


Asunto(s)
Hipoxia/enzimología , Neoplasias/enzimología , Proteínas Nucleares/metabolismo , Oxígeno/metabolismo , Animales , Coenzima A Ligasas/genética , Coenzima A Ligasas/metabolismo , Humanos , Hipoxia/genética , Hipoxia/metabolismo , Complejo Cetoglutarato Deshidrogenasa/genética , Complejo Cetoglutarato Deshidrogenasa/metabolismo , Lipoilación , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mitocondrias/enzimología , Mitocondrias/genética , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Proteínas Nucleares/genética , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora , Ácido Tióctico/metabolismo
7.
Plant J ; 98(4): 745-758, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30729601

RESUMEN

Limber pine (Pinus flexilis) is a keystone species of high-elevation forest ecosystems of western North America, but some parts of the geographic range have high infection and mortality from the non-native white pine blister rust caused byCronartium ribicola. Genetic maps can provide essential knowledge for understanding genetic disease resistance as well as local adaptation to changing climates. Exome-seq was performed to construct high-density genetic maps in two seed families. Composite maps positioned 9612 unigenes across 12 linkage groups (LGs). Syntenic analysis of genome structure revealed that the majority of orthologs were positional orthologous genes (POGs) with localization on homologousLGs among conifer species. Gene ontology (GO) enrichment analysis showed relatively fewer constraints forPOGs with putative roles in adaptation to environments and relatively more conservation forPOGs with roles in basic cell function and maintenance. The mapped genes included 639 nucleotide-binding site leucine-rich repeat genes (NBS-LRRs), 290 receptor-like protein kinase genes (RLKs), and 1014 genes with potential roles in the defense response and induced systemic resistance to attack by pathogens. Orthologous loci for resistance to rust pathogens were identified and were co-positioned with multiple members of theR gene family, revealing the evolutionary pressure acting upon them. This high-density genetic map provides a genomic resource and practical tool for breeding and genetic conservation programs, with applications in genome-wide association studies (GWASs), the characterization of functional genes underlying complex traits, and the sequencing and assembly of the full-length genomes of limber pine and relatedPinus species.


Asunto(s)
Mapeo Cromosómico , Resistencia a la Enfermedad/genética , Genoma de Planta , Genómica , Pinus/genética , Secuencia de Bases , Basidiomycota , Cruzamiento , Exoma , Ontología de Genes , Ligamiento Genético , Estudio de Asociación del Genoma Completo , Genotipo , Filogenia , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Polimorfismo de Nucleótido Simple , Alineación de Secuencia
8.
Lab Invest ; 99(3): 399-410, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30291325

RESUMEN

The dual specificity phosphatase slingshot homolog 1 (SSH1) contributes to actin remodeling by dephosphorylating and activating the actin-severing protein cofilin. The reorganization of the actin cytoskeleton has been implicated in chronic hypertension and the subsequent mechano-adaptive rearrangement of vessel wall components. Therefore, using a novel Ssh1-/- mouse model, we investigated the potential role of SSH1 in angiotensin II (Ang II)-induced hypertension, and vascular remodeling. We found that loss of SSH1 did not produce overt phenotypic changes and that baseline blood pressures as well as heart rates were comparable between Ssh1+/+ and Ssh1-/- mice. Although 14 days of Ang II treatment equally increased systolic blood pressure in both genotypes, histological assessment of aortic samples indicated that medial thickening was exacerbated by the loss of SSH1. Consequently, reverse-transcription quantitative PCR analysis of the transcripts from Ang II-infused animals confirmed increased aortic expression levels of fibronectin, and osteopontin in Ssh1-/- when compared to wild-type mice. Mechanistically, our data suggest that fibrosis in SSH1-deficient mice occurs by a process that involves aberrant responses to Ang II-induced TGFß1. Taken together, our work indicates that Ang II-dependent fibrotic gene expression and vascular remodeling, but not the Ang II-induced pressor response, are modulated by SSH1-mediated signaling pathways and SSH1 activity is protective against Ang II-induced remodeling in the vasculature.


Asunto(s)
Angiotensina II/metabolismo , Fosfoproteínas Fosfatasas/metabolismo , Remodelación Vascular/fisiología , Animales , Aorta/metabolismo , Aorta/patología , Modelos Animales de Enfermedad , Femenino , Fibrosis , Hipertensión/etiología , Hipertensión/metabolismo , Hipertensión/patología , Hipertrofia , Masculino , Ratones , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Noqueados , Fosfoproteínas Fosfatasas/deficiencia , Fosfoproteínas Fosfatasas/genética , Factor de Crecimiento Transformador beta1/metabolismo , Remodelación Vascular/genética
9.
Virol J ; 16(1): 118, 2019 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-31623644

RESUMEN

BACKGROUND: Mycoviruses were recently discovered in the white pine blister rust (WPBR) fungus Cronartium ribicola (J.C. Fisch.). Detection and characterization of their double stranded RNA (dsRNA) would facilitate understanding of pathogen virulence and disease pathogenesis in WPBR systems. METHODS: Full-length cDNAs were cloned from the dsRNAs purified from viral-infected C. ribicola, and their cDNA sequences were determined by DNA sequencing. Evolutionary relationships of the dsRNAs with related mycoviruses were determined by phylogenetic analysis. Dynamic distributions of the viral RNAs within samples of their fungal host C. ribicola were investigated by measurement of viral genome prevalence and viral gene expression. RESULTS: In this study we identified and characterized five novel dsRNAs from C. ribicola, designated as Cronartium ribicola totivirus 1-5 (CrTV1 to CrTV5). These dsRNA sequences encode capsid protein and RNA-dependent RNA polymerase with significant homologies to dsRNA viruses of the family Totiviridae. Phylogenetic analysis showed that the CrTVs were grouped into two distinct clades. CrTV2 through CrTV5 clustered within the genus Totivirus. CrTV1 along with a few un-assigned dsRNAs constituted a distinct phyletic clade that is genetically distant from presently known genera in the Totiviridae family, indicating that CrTV1 represents a novel genus in the Totiviridae family. The CrTVs were prevalent in fungal samples obtained from infected western white pine, whitebark pine, and limber pines. Viral RNAs were generally expressed at higher levels during in planta mycelium growth than in aeciospores and urediniospores. CrTV4 was significantly associated with C. ribicola virulent pathotype and specific C. ribicola host tree species, suggesting dsRNAs as potential tools for dissection of pathogenic mechanisms of C. ribicola and diagnosis of C. ribicola pathotypes. CONCLUSION: Phylogenetic and expression analyses of viruses in the WPBR pathogen, C. ribicola, have enchanced our understanding of virus diversity in the family Totiviridae, and provided a potential strategy to utilize pathotype-associated mycoviruses to control fungal forest diseases.


Asunto(s)
Basidiomycota/virología , Micelio/patogenicidad , Pinus/microbiología , Enfermedades de las Plantas/microbiología , ARN Bicatenario/fisiología , Totiviridae/fisiología , Basidiomycota/genética , Basidiomycota/crecimiento & desarrollo , Basidiomycota/patogenicidad , Genoma Viral/genética , Micelio/genética , Micelio/crecimiento & desarrollo , Micelio/virología , Filogenia , Pinus/clasificación , ARN Bicatenario/clasificación , ARN Bicatenario/genética , ARN Viral/genética , Totiviridae/clasificación , Totiviridae/genética , Transcripción Genética , Proteínas Virales/genética , Virulencia
10.
J Ment Health ; 28(1): 64-70, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30468100

RESUMEN

BACKGROUND: The OpenNotes initiative provides patients online access to their clinical notes. Mental health clinicians in the Veterans Health Administration report a need for guidance on how to provide care, write notes, and discuss them in the context of OpenNotes. AIM: To provide mental health clinicians recommendations identified by patients and clinicians that help them effectively practice in the context of OpenNotes. METHOD: Twenty-eight mental health clinicians and 28 patients in mental health care participated in semi-structured interviews about their experiences and perceptions with OpenNotes. A rapid review approach was used to analyze transcripts. RESULTS: Analysis of interviews identified three domains of advice for mental health clinicians: writing notes that maintain the therapeutic relationship, communicating with patients about their notes and utilizing clinical notes as a patient resource to enhance care. Specific recommendations are provided. CONCLUSION: Findings provide mental health clinicians with guidance from service users and clinicians on how to leverage clinical notes to maintain - and potentially enhance -therapeutic relationships in a healthcare system in which patients are able to read their mental health notes online.


Asunto(s)
Registros Electrónicos de Salud/normas , Servicios de Salud Mental/normas , Relaciones Médico-Paciente , Adulto , Femenino , Comunicación en Salud , Humanos , Masculino , Persona de Mediana Edad , Programas Informáticos , Veteranos
11.
Am J Public Health ; 108(S3): S179-S182, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30192670

RESUMEN

Following Hurricane Katrina, the uniformed US Public Health Service created an updated system through which its officers participated in emergency responses. The Rapid Deployment Force (RDF) concept, begun in 2006, involved five teams of officers with diverse clinical and public health skill sets organized into an incident command system led by a team commander. Each team can deploy within 12 hours, according to a defined but flexible schedule. The core RDF mission is to set up and provide care for up to 250 patients, primarily persons with chronic diseases or disabilities, in a temporary federal medical station. Between 2006 and 2016, the RDF 3 team deployed multiple times in response to natural disasters and public health emergencies. Notable responses included Hurricane Sandy in 2012, the unaccompanied children mission in 2014, and the Louisiana floods in 2016. Lessons learned from the RDF 3 experience include the need for both clinical and public health capacity, the value of having special mental health resources, the benefits of collaboration with other federal medical responders, and recognition of the large burden of chronic disease management issues following natural disasters.


Asunto(s)
Planificación en Desastres , Desastres/historia , Salud Pública , Tormentas Ciclónicas/historia , Inundaciones/historia , Historia del Siglo XXI , Humanos , Louisiana , New Jersey
12.
J Chem Phys ; 148(19): 194303, 2018 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-30307253

RESUMEN

The excited state relaxation dynamics of adenosine and adenosine monophosphate were studied at multiple excitation energies using femtosecond time-resolved photoelectron spectroscopy in a liquid water microjet. At pump energies of 4.69-4.97 eV, the lowest ππ* excited state, S1, was accessed and its decay dynamics were probed via ionization at 6.20 eV. By reversing the role of the pump and probe lasers, a higher-lying ππ* state was excited at 6.20 eV and its time-evolving photoelectron spectrum was monitored at probe energies of 4.69-4.97 eV. The S1 ππ* excited state was found to decay with a lifetime ranging from ∼210 to 250 fs in adenosine and ∼220 to 250 fs in adenosine monophosphate. This lifetime drops with increasing pump photon energy. Signal from the higher-lying ππ* excited state decayed on a time scale of ∼320 fs and was measureable only in adenosine monophosphate.

13.
Plant Mol Biol ; 95(4-5): 359-374, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28861810

RESUMEN

KEY MESSAGE: RNA-seq analysis on whitebark pine needles demonstrated that methyl jasmonate (MeJA)-triggered transcriptome re-programming substantially overlapped with defense responses against insects and fungal pathogens in Pinus species, increasing current knowledge regarding induced systemic resistance (ISR) to pathogens and pests in whitebark pine. Many whitebark pine populations are in steep decline due to high susceptibility to mountain pine beetle and the non-native white pine blister rust (WPBR). Resistance, including induced systemic resistance (ISR), is not well characterized in whitebark pine, narrowing the current options for increasing the success of restoration and breeding programs. Exogenous jasmonates are known to trigger ISR by activating the plant's immune system through regulation of gene expression to produce chemical defense compounds. This study reports profiles of whitebark pine needle transcriptomes, following methyl jasmonate (MeJA) treatment using RNA-seq. A MeJA-responsive transcriptome was de novo assembled and transcriptome profiling identified a set of differentially expressed genes (DEGs), revealing 1422 up- and 999 down-regulated transcripts with at least twofold change (FDR corrected p < 0.05) in needle tissues in response to MeJA application. GO analysis revealed that these DEGs have putative functions in plant defense signalling, transcription regulation, biosyntheses of secondary metabolites, and other biological processes. Lineage-specific expression of defense-related genes was characterized through comparison with MeJA signalling in model plants. In particular, MeJA-triggered transcriptome re-programming substantially overlapped with defense responses against WPBR and insects in related Pinus species, suggesting that MeJA may be used to improve whitebark pine resistance to pathogens/pests. Our study provides new insights into molecular mechanisms and metabolic pathways involved in whitebark pine ISR. DEGs identified in this study can be used as candidates to facilitate identification of genomic variation contributing to host resistance and aid in breeding selection of elite genotypes with better adaptive fitness to environmental stressors in this endangered tree species.


Asunto(s)
Acetatos/farmacología , Ciclopentanos/farmacología , Oxilipinas/farmacología , Pinus/genética , Enfermedades de las Plantas/inmunología , Transcriptoma/efectos de los fármacos , Basidiomycota/fisiología , Cruzamiento , Resistencia a la Enfermedad , Perfilación de la Expresión Génica , Genotipo , Pinus/efectos de los fármacos , Pinus/microbiología , Enfermedades de las Plantas/microbiología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/genética , Hojas de la Planta/microbiología , Análisis de Secuencia de ARN , Árboles
14.
Plant Biotechnol J ; 15(9): 1149-1162, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28176454

RESUMEN

Molecular breeding incorporates efficient tools to increase rust resistance in five-needle pines. Susceptibility of native five-needle pines to white pine blister rust (WPBR), caused by the non-native invasive fungus Cronartium ribicola (J.C. Fisch.), has significantly reduced wild populations of these conifers in North America. Major resistance (R) genes against specific avirulent pathotypes have been found in several five-needle pine species. In this study, we screened genic SNP markers by comparative transcriptome and genetic association analyses and constructed saturated linkage maps for the western white pine (Pinus monticola) R locus (Cr2). Phenotypic segregation was measured by a hypersensitive reaction (HR)-like response on the needles and disease symptoms of cankered stems post inoculation by the C. ribicola avcr2 race. SNP genotypes were determined by HRM- and TaqMan-based SNP genotyping. Saturated maps of the Cr2-linkage group (LG) were constructed in three seed families using a total of 34 SNP markers within 21 unique genes. Cr2 was consistently flanked by contig_2142 (encoding a ruvb-like protein) and contig_3772 (encoding a delta-fatty acid desaturase) across the three seed families. Cr2 was anchored to the Pinus consensus LG-1, which differs from LGs where other R loci of Pinus species were mapped. GO annotation identified a set of NBS-LRR and other resistance-related genes as R candidates in the Cr2 region. Association of one nonsynonymous SNP locus of an NBS-LRR gene with Cr2-mediated phenotypes provides a valuable tool for marker-assisted selection (MAS), which will shorten the breeding cycle of resistance screening and aid in the restoration of WPBR-disturbed forest ecosystems.


Asunto(s)
Basidiomycota/fisiología , Resistencia a la Enfermedad/genética , Pinus/genética , Enfermedades de las Plantas/inmunología , Proteínas de Plantas/metabolismo , Transcriptoma , Cruzamiento , Mapeo Cromosómico , Perfilación de la Expresión Génica , Ontología de Genes , Ligamiento Genético , Sitios Genéticos/genética , Genotipo , Pinus/inmunología , Pinus/microbiología , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Polimorfismo de Nucleótido Simple/genética , Semillas/genética , Semillas/inmunología , Semillas/microbiología
15.
J Med Internet Res ; 19(6): e208, 2017 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-28615152

RESUMEN

BACKGROUND: As part of the national OpenNotes initiative, the Veterans Health Administration (VHA) provides veterans online access to their clinical progress notes, raising concern in mental health settings. OBJECTIVE: The aim of this study was to examine the perspectives and experiences of mental health clinicians with OpenNotes to better understand how OpenNotes may be affecting mental health care. METHODS: We conducted individual semi-structured interviews with 28 VHA mental health clinicians and nurses. Transcripts were analyzed using a thematic analysis approach, which allows for both inductive and deductive themes to be explored using an iterative, constant comparative coding process. RESULTS: OpenNotes is changing VHA mental health care in ways that mental health clinicians perceive as both challenging and beneficial. At the heart of these changes is a shifting power distribution within the patient-clinician relationship. Some clinicians view OpenNotes as an opportunity to better partner with patients, whereas others feel that it has the potential to undo the therapeutic relationship. Many clinicians are uncomfortable with OpenNotes, but acknowledge that this discomfort could both improve and diminish care and documentation practices. Specifically, we found that (1) OpenNotes is empowering patients, (2) OpenNotes is affecting how clinicians build and maintain the therapeutic relationship, and (3) mental health clinicians are adjusting their practices to protect patients and themselves from adverse consequences of OpenNotes. CONCLUSIONS: Our findings suggest that future research should monitor whether OpenNotes notes facilitates stronger patient-clinician relationships, enhancing patient-centered mental health care, or diminishes the quality of mental health care through disruptions in the therapeutic relationship and reduced documentation.


Asunto(s)
Internet/estadística & datos numéricos , Registros Médicos/normas , Salud Mental/normas , Atención Dirigida al Paciente/métodos , Telemedicina/métodos , Femenino , Humanos , Masculino , Percepción , Relaciones Médico-Paciente , Investigación Cualitativa , Estados Unidos
16.
J Nurs Scholarsh ; 49(6): 661-669, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28960808

RESUMEN

PURPOSE: The effects of climate change are far-reaching and multifactorial, with potential impacts on food security and conflict. Large population movements, whether from the aftermath of natural disasters or resulting from conflict, can precipitate the need for humanitarian response in what can become complex humanitarian emergencies (CHEs). Nurses need to be prepared to respond to affected communities in need, whether the emergency is domestic or global. The purpose of the article is to describe a novel course for nursing students interested in practice within the confines of CHEs and natural disasters. METHODS AND FRAMEWORK: The authors used the Sphere Humanitarian Charter and Minimum Standards as a practical framework to inform the course development. They completed a review of the literature on the interaction on climate change, conflict and health, and competencies related to working CHEs. Resettled refugees, as well as experts in the area of humanitarian response, recovery, and mitigation from the Centers for Disease Control and Prevention and nongovernmental organizations further informed the development of the course. CLINICAL RELEVANCE: This course prepares the nursing workforce to respond appropriately to large population movements that may arise from the aftermath of natural disasters or conflict, both of which can comprise a complex humanitarian disaster. Using The Sphere Project e-learning course, students learn about the Sphere Project, which works to ensure accountability and quality in humanitarian response and offers core minimal standards for technical assistance. These guidelines are seen globally as the gold standard for humanitarian response and address many of the competencies for disaster nursing (http://www.sphereproject.org/learning/e-learning-course/).


Asunto(s)
Altruismo , Curriculum , Planificación en Desastres , Educación en Enfermería/organización & administración , Cambio Climático , Desastres , Humanos
17.
BMC Genomics ; 17(1): 753, 2016 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-27663193

RESUMEN

BACKGROUND: Linkage of DNA markers with phenotypic traits provides essential information to dissect clustered genes with potential phenotypic contributions in a target genome region. Pinus flexilis E. James (limber pine) is a keystone five-needle pine species in mountain-top ecosystems of North America. White pine blister rust (WPBR), caused by a non-native fungal pathogen Cronartium ribicola (J.C. Fisch.), has resulted in mortality in this conifer species and is still spreading through the distribution. The objective of this research was to develop P. flexilis transcriptome-wide single nucleotide polymorphism (SNP) markers using RNA-seq analysis for genetic mapping of the major gene (Cr4) that confers complete resistance to C. ribicola. RESULTS: Needle tissues of one resistant and two susceptible seedling families were subjected to RNA-seq analysis. In silico SNP markers were uncovered by mapping the RNA-seq reads back to the de novo assembled transcriptomes. A total of 110,573 in silico SNPs and 2,870 indels were identified with an average of 3.7 SNPs per Kb. These SNPs were distributed in 17,041 unigenes. Of these polymorphic P. flexilis unigenes, 6,584 were highly conserved as compared to the genome sequence of P. taeda L (loblolly pine). High-throughput genotyping arrays were designed and were used to search for Cr4-linked genic SNPs in megagametophyte populations of four maternal trees by haploid-segregation analysis. A total of 32 SNP markers in 25 genes were localized on the Cr4 linkage group (LG). Syntenic relationships of this Cr4-LG map with the model conifer species P. taeda anchored Cr4 on Pinus consensus LG8, indicating that R genes against C. ribicola have evolved independently in different five-needle pines. Functional genes close to Cr4 were annotated and their potential roles in Cr4-mediated resistance were further discussed. CONCLUSIONS: We demonstrated a very effective, low-cost strategy for developing a SNP genetic map of a phenotypic trait of interest. SNP discovery through transcriptome comparison was integrated with high-throughput genotyping of a small set of in silico SNPs. This strategy may be applied to mapping any trait in non-model plant species that have complex genomes. Whole transcriptome sequencing provides a powerful tool for SNP discovery in conifers and other species with complex genomes, for which sequencing and annotation of complex genomes is still challenging. The genic SNP map for the consensus Cr4-LG may help future molecular breeding efforts by enabling both Cr4 positional characterization and selection of this gene against WPBR.

18.
J Chem Phys ; 144(18): 184503, 2016 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-27179491

RESUMEN

The excited state relaxation dynamics of the solvated electron in H2O and D2O are investigated using time-resolved photoelectron spectroscopy in a liquid microjet. The data show that the initial excited state decays on a time scale of 75 ± 12 fs in H2O and 102 ± 8 fs in D2O, followed by slower relaxation on time scales of 400 ± 70 fs and 390 ± 70 fs that are isotopically invariant within the precision of our measurements. Based on the time evolution of the transient signals, the faster and slower time constants are assigned to p → s internal conversion (IC) of the hydrated electron and relaxation on the ground electronic state, respectively. This assignment is consistent with the non-adiabatic mechanism for relaxation of the hydrated electron and yields an isotope effect of 1.4 ± 0.2 for IC of the hydrated electron.

19.
BMC Genomics ; 16: 678, 2015 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-26338692

RESUMEN

BACKGROUND: The fungus Cronartium ribicola (Cri) is an economically and ecologically important forest pathogen that causes white pine blister rust (WPBR) disease on five-needle pines. To cause stem cankers and kill white pine trees the fungus elaborates a life cycle with five stages of spore development on five-needle pines and the alternate host Ribes plants. To increase our understanding of molecular WP-BR interactions, here we report genome-wide transcriptional profile analysis of C. ribicola using RNA-seq. RESULTS: cDNA libraries were constructed from aeciospore, urediniospore, and western white pine (Pinus monticola) tissues post Cri infection. Over 200 million RNA-seq 100-bp paired-end (PE) reads from rust fungal spores were de novo assembled and a reference transcriptome was generated with 17,880 transcripts that were expressed from 13,629 unigenes. A total of 734 unique proteins were predicted as a part of the Cri secretome from complete open reading frames (ORFs), and 41 % of them were Cronartium-specific. This study further identified a repertoire of candidate effectors and other pathogenicity determinants. Differentially expressed genes (DEGs) were identified to gain an understanding of molecular events important during the WPBR fungus life cycle by comparing Cri transcriptomes at different infection stages. Large-scale changes of in planta gene expression profiles were observed, revealing that multiple fungal biosynthetic pathways were enhanced during mycelium growth inside infected pine stem tissues. Conversely, many fungal genes that were up-regulated at the urediniospore stage appeared to be signalling components and transporters. The secreted fungal protein genes that were up-regulated in pine needle tissues during early infection were primarily associated with cell wall modifications, possibly to mask the rust pathogen from plant defenses. CONCLUSION: This comprehensive transcriptome profiling substantially improves our current understanding of molecular WP-BR interactions. The repertoire of candidate effectors and other putative pathogenicity determinants identified here are valuable for future functional analysis of Cri virulence and pathogenicity.


Asunto(s)
Basidiomycota/genética , Perfilación de la Expresión Génica , Pinus/microbiología , Enfermedades de las Plantas/microbiología , Transcriptoma , Análisis por Conglomerados , Biología Computacional/métodos , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Anotación de Secuencia Molecular , Datos de Secuencia Molecular
20.
J Chem Phys ; 142(23): 234501, 2015 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-26093562

RESUMEN

The charge-transfer-to-solvent dynamics (CTTS) and excited state relaxation mechanism of the solvated electron in methanol are studied by time-resolved photoelectron spectroscopy on a liquid methanol microjet by means of two-pulse and three-pulse experiments. In the two-pulse experiment, CTTS excitation is followed by a probe photoejection pulse. The resulting time-evolving photoelectron spectrum reveals multiple time scales characteristic of relaxation and geminate recombination of the initially generated electron which are consistent with prior results from transient absorption. In the three-pulse experiment, the relaxation dynamics of the solvated electron following electronic excitation are measured. The internal conversion lifetime of the excited electron is found to be 130 ± 40 fs, in agreement with extrapolated results from clusters and the non-adiabatic relaxation mechanism.

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