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1.
CBE Life Sci Educ ; 22(1): ar2, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36525283

RESUMO

Our understanding of how active learning affects different groups of students is still developing. One group often overlooked in higher education research is students with disabilities. Two of the most commonly occurring disabilities on college campuses are attention-deficit/hyperactivity disorder (ADHD) and specific learning disorders (SLD). We investigated how the incorporation of active-learning practices influences the learning and self-advocacy experiences of students with ADHD and/or SLD (ADHD/SLD) in undergraduate science, technology, engineering, and mathematics (STEM) courses. Semistructured interviews were conducted with 25 STEM majors with ADHD/SLD registered with a campus disability resource center at a single university, and data were analyzed using qualitative methods. Participants described how they perceived active learning in their STEM courses to support or hinder their learning and how active learning affected their self-advocacy. Many of the active-learning barriers could be attributed to issues related to fidelity of implementation of a particular active-learning strategy and limited awareness of universal design for learning. Active learning was also reported to influence self-advocacy for some participants, and examples of self-advocacy in active-learning STEM courses were identified. Defining the supports and barriers perceived by students with ADHD/SLD is a crucial first step in developing more-inclusive active-learning STEM courses. Suggestions for research and teaching are provided.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Deficiências da Aprendizagem , Humanos , Aprendizagem Baseada em Problemas , Estudantes , Matemática , Tecnologia/educação
2.
Front Cell Dev Biol ; 9: 681734, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222251

RESUMO

To cause the devastating rice blast disease, the hemibiotrophic fungus Magnaporthe oryzae produces invasive hyphae (IH) that are enclosed in a plant-derived interfacial membrane, known as the extra-invasive hyphal membrane (EIHM), in living rice cells. Little is known about when the EIHM is disrupted and how the disruption contributes to blast disease. Here we show that the disruption of the EIHM correlates with the hyphal growth stage in first-invaded susceptible rice cells. Our approach utilized GFP that was secreted from IH as an EIHM integrity reporter. Secreted GFP (sec-GFP) accumulated in the EIHM compartment but appeared in the host cytoplasm when the integrity of the EIHM was compromised. Live-cell imaging coupled with sec-GFP and various fluorescent reporters revealed that the loss of EIHM integrity preceded shrinkage and eventual rupture of the rice vacuole. The vacuole rupture coincided with host cell death, which was limited to the invaded cell with presumed closure of plasmodesmata. We report that EIHM disruption and host cell death are landmarks that delineate three distinct infection phases (early biotrophic, late biotrophic, and transient necrotrophic phases) within the first-invaded cell before reestablishment of biotrophy in second-invaded cells. M. oryzae effectors exhibited infection phase-specific localizations, including entry of the apoplastic effector Bas4 into the host cytoplasm through the disrupted EIHM during the late biotrophic phase. Understanding how infection phase-specific cellular dynamics are regulated and linked to host susceptibility will offer potential targets that can be exploited to control blast disease.

3.
CBE Life Sci Educ ; 20(2): ar17, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33769838

RESUMO

Self-advocacy is linked to the success and retention of students with disabilities in college. Self-advocacy is defined as communicating individual wants, needs, and rights to determine and pursue required accommodations. While self-advocacy is linked to academic success, little is known about how students with disabilities in science, technology, engineering, and mathematics (STEM) practice self-advocacy. We previously developed a model of self-advocacy for STEM students with attention-deficit/hyperactivity disorder (ADHD) and/or specific learning disabilities (SLD). Here, we use this model to examine what factors support or hinder self-advocacy in undergraduate STEM courses. We conducted semistructured interviews with 25 STEM majors with ADHD and/or SLD and used qualitative approaches to analyze our data. We found internal factors, or factors within a participant, and external factors, the situations and people, described by our participants, that influenced self-advocacy. These factors often interacted and functioned as a support or barrier, depending on the individuals and their unique experiences. We developed a model to understand how factors supported or hindered self-advocacy in STEM. Supporting factors contributed to a sense of comfort and security for our participants and informed their perceptions that accommodation use was accepted in a STEM course. We share implications for research and teaching based on our results.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Deficiências da Aprendizagem , Humanos , Deficiências da Aprendizagem/etiologia , Matemática , Estudantes , Tecnologia
4.
mBio ; 12(1)2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33563831

RESUMO

Rice blast disease caused by Magnaporthe oryzae is a devastating disease of cultivated rice worldwide. Infections by this fungus lead to a significant reduction in rice yields and threats to food security. To gain better insight into growth and cell death in M. oryzae during infection, we characterized two predicted M. oryzae metacaspase proteins, MoMca1 and MoMca2. These proteins appear to be functionally redundant and can complement the yeast Yca1 homologue. Biochemical analysis revealed that M. oryzae metacaspases exhibited Ca2+-dependent caspase activity in vitro Deletion of both MoMca1 and MoMca2 in M. oryzae resulted in reduced sporulation, delay in conidial germination, and attenuation of disease severity. In addition, the double ΔMomca1mca2 mutant strain showed increased radial growth in the presence of oxidative stress. Interestingly, the ΔMomca1mca2 strain showed an increased accumulation of insoluble aggregates compared to the wild-type strain during vegetative growth. Our findings suggest that MoMca1 and MoMca2 promote the clearance of insoluble aggregates in M. oryzae, demonstrating the important role these metacaspases have in fungal protein homeostasis. Furthermore, these metacaspase proteins may play additional roles, like in regulating stress responses, that would help maintain the fitness of fungal cells required for host infection.IMPORTANCEMagnaporthe oryzae causes rice blast disease that threatens global food security by resulting in the severe loss of rice production every year. A tightly regulated life cycle allows M. oryzae to disarm the host plant immune system during its biotrophic stage before triggering plant cell death in its necrotrophic stage. The ways M. oryzae navigates its complex life cycle remain unclear. This work characterizes two metacaspase proteins with peptidase activity in M. oryzae that are shown to be involved in the regulation of fungal growth and development prior to infection by potentially helping maintain fungal fitness. This study provides new insights into the role of metacaspase proteins in filamentous fungi by illustrating the delays in M. oryzae morphogenesis in the absence of these proteins. Understanding the mechanisms by which M. oryzae morphology and development promote its devastating pathogenicity may lead to the emergence of proper methods for disease control.


Assuntos
Ascomicetos/enzimologia , Ascomicetos/patogenicidade , Caspases/genética , Caspases/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Oryza/microbiologia , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Caspases/classificação , Biologia Computacional , Regulação Fúngica da Expressão Gênica , Genoma Fúngico , Estresse Oxidativo , Doenças das Plantas/microbiologia , Proteínas de Saccharomyces cerevisiae/genética , Virulência
5.
Fungal Genet Biol ; 146: 103472, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32980454

RESUMO

The arrangement of the nuclear envelope in the rice blast fungus, Magnaporthe oryzae, was previously undetermined. Here, we identified two conserved components of the nuclear envelope, a core nucleoporin, Nup84, and an inner nuclear membrane protein, Src1. Live-cell super-resolution structured illumination microscopy revealed that Nup84-tdTomato and Src1-EGFP colocalized within the nuclear envelope during interphase and that Nup84-tdTomato remained associated with the dividing nucleus. We also found that appressorium development involved a mitotic nuclear migration event through the germ tube.


Assuntos
Ascomicetos/genética , Proteínas Fúngicas/genética , Mitose/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Ascomicetos/patogenicidade , Transporte Biológico/genética , Hifas/genética , Hifas/patogenicidade , Membrana Nuclear/genética , Oryza/genética , Oryza/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
6.
Fungal Genet Biol ; 126: 56-60, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30794949

RESUMO

To cause rice blast disease, Magnaporthe oryzae must properly organize microtubules and position nuclei during colonization of host cells. Live cell confocal imaging of fluorescently-tagged microtubules and nuclei of M. oryzae invasive hyphae reveals that microtubules form a cage-like arrangement around nuclei during interphase and that the mitotic spindle forms and mediates nuclear migration while integrity of the nuclear envelope is lost. Our results also unveil a strikingly-angled spindle during nuclear migration through the narrow invasive hyphal peg, suggesting a yet-to-be discovered mechanism of mitotic nuclear migration when invasive hyphae move to adjacent rice cells.


Assuntos
Magnaporthe/patogenicidade , Mitose , Oryza/microbiologia , Doenças das Plantas/microbiologia , Fuso Acromático/metabolismo , Transporte Biológico , Núcleo Celular/metabolismo , Proteínas Fúngicas/genética , Hifas/metabolismo , Microtúbulos/metabolismo , Oryza/citologia
7.
Mycology ; 9(3): 202-210, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30181926

RESUMO

Magnaporthe oryzae is a filamentous fungus, which causes significant destruction to cereal crops worldwide. To infect plant cells, the fungus develops specialised constricted structures such as the penetration peg and the invasive hyphal peg. Live-cell imaging of M. oryzae during plant infection reveals that nuclear migration occurs during intermediate mitosis, in which the nuclear envelope neither completely disassembles nor remains entirely intact. Remarkably, in M. oryzae, mitotic nuclei show incredible malleability while undergoing confined migration through the constricted penetration and invasive hyphal pegs. Here, we review early events in plant infection, discuss intermediate mitosis, and summarise current knowledge of intermediate mitotic nuclear migration in M. oryzae.

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