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1.
J Microbiol Biol Educ ; 23(2)2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36061313

RESUMO

The Genomics Education Partnership (GEP) engages students in a course-based undergraduate research experience (CURE). To better understand the student attributes that support success in this CURE, we asked students about their attitudes using previously published scales that measure epistemic beliefs about work and science, interest in science, and grit. We found, in general, that the attitudes students bring with them into the classroom contribute to two outcome measures, namely, learning as assessed by a pre- and postquiz and perceived self-reported benefits. While the GEP CURE produces positive outcomes overall, the students with more positive attitudes toward science, particularly with respect to epistemic beliefs, showed greater gains. The findings indicate the importance of a student's epistemic beliefs to achieving positive learning outcomes.

2.
Cells ; 10(4)2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33920019

RESUMO

Histone acetylation is directly related to gene expression. In yeast, the acetyltransferase general control nonderepressible-5 (GCN5) targets histone H3 and associates with transcriptional co-activators alteration/deficiency in activation-2 (ADA2) and alteration/deficiency in activation-3 (ADA3) in complexes like SAGA. Arabidopsis thaliana has two genes encoding proteins, designated ADA3a and ADA3b, that correspond to yeast ADA3. We investigated the role of ADA3a and ADA3b in regulating gene expression during flowering time. Specifically, we found that knock out mutants ada3a-2 and the double mutant ada3a-2 ada3b-2 lead to early flowering compared to the wild type plants under long day (LD) conditions and after moving plants from short days to LD. Consistent with ADA3a being a repressor of floral initiation, FLOWERING LOCUS T (FT) expression was increased in ada3a mutants. In contrast, other genes involved in multiple pathways leading to floral transition, including FT repressors, players in GA signaling, and members of the SPL transcriptional factors, displayed reduced expression. Chromatin immunoprecipitation analysis revealed that ADA3a affects the histone H3K14 acetylation levels in SPL3, SPL5, RGA, GAI, and SMZ loci. In conclusion, ADA3a is involved in floral induction through a GCN5-containing complex that acetylates histone H3 in the chromatin of flowering related genes.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Flores/fisiologia , Proteínas Nucleares/metabolismo , Transcrição Gênica , Acetilação , Arabidopsis/genética , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , DNA Bacteriano/genética , Epistasia Genética , Flores/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Histonas/metabolismo , Mutação/genética , Proteínas Nucleares/química , Proteínas Nucleares/genética , Fenótipo , Filogenia , Ligação Proteica , Domínios Proteicos , Homologia de Sequência de Aminoácidos , Fatores de Tempo
3.
Artigo em Inglês | MEDLINE | ID: mdl-32148609

RESUMO

A hallmark of the research experience is encountering difficulty and working through those challenges to achieve success. This ability is essential to being a successful scientist, but replicating such challenges in a teaching setting can be difficult. The Genomics Education Partnership (GEP) is a consortium of faculty who engage their students in a genomics Course-Based Undergraduate Research Experience (CURE). Students participate in genome annotation, generating gene models using multiple lines of experimental evidence. Our observations suggested that the students' learning experience is continuous and recursive, frequently beginning with frustration but eventually leading to success as they come up with defendable gene models. In order to explore our "formative frustration" hypothesis, we gathered data from faculty via a survey, and from students via both a general survey and a set of student focus groups. Upon analyzing these data, we found that all three datasets mentioned frustration and struggle, as well as learning and better understanding of the scientific process. Bioinformatics projects are particularly well suited to the process of iteration and refinement because iterations can be performed quickly and are inexpensive in both time and money. Based on these findings, we suggest that a dynamic of "formative frustration" is an important aspect for a successful CURE.

4.
Planta ; 248(3): 613-628, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29846775

RESUMO

MAIN CONCLUSION: The histone acetyltransferase GCN5 and associated transcriptional coactivator ADA2b are required to couple endoreduplication and trichome branching. Mutation of ADA2b also disrupts the relationship between ploidy and leaf cell size. Dynamic chromatin structure has been established as a general mechanism by which gene function is temporally and spatially regulated, but specific chromatin modifier function is less well understood. To address this question, we have investigated the role of the histone acetyltransferase GCN5 and the associated coactivator ADA2b in developmental events in Arabidopsis thaliana. Arabidopsis plants with T-DNA insertions in GCN5 (also known as HAG1) or ADA2b (also known as PROPORZ1) display pleiotropic phenotypes including dwarfism and floral defects affecting fertility. We undertook a detailed characterization of gcn5 and ada2b phenotypic effects in rosette leaves and trichomes to establish a role for epigenetic control in these developmental processes. ADA2b and GCN5 play specific roles in leaf tissue, affecting cell growth and division in rosette leaves often in complex and even opposite directions. Leaves of gcn5 plants display overall reduced ploidy levels, while ada2b-1 leaves show increased ploidy. Endoreduplication leading to increased ploidy is also known to contribute to normal trichome morphogenesis. We demonstrate that gcn5 and ada2b mutants display alterations in the number and patterning of trichome branches, with ada2b-1 and gcn5-1 trichomes being significantly less branched, while gcn5-6 trichomes show increased branching. Elongation of the trichome stalk and branches also vary in different mutant backgrounds, with stalk length having an inverse relationship with branch number. Taken together, our data indicate that, in Arabidopsis, leaves and trichomes ADA2b and GCN5 are required to couple nuclear content with cell growth and morphogenesis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Histona Acetiltransferases/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Tricomas/crescimento & desenvolvimento , Arabidopsis/enzimologia , Arabidopsis/genética , Arabidopsis/metabolismo , Citometria de Fluxo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Microscopia de Interferência , Ploidias , Reação em Cadeia da Polimerase
5.
CBE Life Sci Educ ; 13(4): 711-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25452493

RESUMO

In their 2012 report, the President's Council of Advisors on Science and Technology advocated "replacing standard science laboratory courses with discovery-based research courses"-a challenging proposition that presents practical and pedagogical difficulties. In this paper, we describe our collective experiences working with the Genomics Education Partnership, a nationwide faculty consortium that aims to provide undergraduates with a research experience in genomics through a scheduled course (a classroom-based undergraduate research experience, or CURE). We examine the common barriers encountered in implementing a CURE, program elements of most value to faculty, ways in which a shared core support system can help, and the incentives for and rewards of establishing a CURE on our diverse campuses. While some of the barriers and rewards are specific to a research project utilizing a genomics approach, other lessons learned should be broadly applicable. We find that a central system that supports a shared investigation can mitigate some shortfalls in campus infrastructure (such as time for new curriculum development, availability of IT services) and provides collegial support for change. Our findings should be useful for designing similar supportive programs to facilitate change in the way we teach science for undergraduates.


Assuntos
Genômica/educação , Currículo , Modelos Educacionais , Desenvolvimento de Programas , Estados Unidos , Universidades
6.
CBE Life Sci Educ ; 13(1): 111-30, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24591510

RESUMO

There is widespread agreement that science, technology, engineering, and mathematics programs should provide undergraduates with research experience. Practical issues and limited resources, however, make this a challenge. We have developed a bioinformatics project that provides a course-based research experience for students at a diverse group of schools and offers the opportunity to tailor this experience to local curriculum and institution-specific student needs. We assessed both attitude and knowledge gains, looking for insights into how students respond given this wide range of curricular and institutional variables. While different approaches all appear to result in learning gains, we find that a significant investment of course time is required to enable students to show gains commensurate to a summer research experience. An alumni survey revealed that time spent on a research project is also a significant factor in the value former students assign to the experience one or more years later. We conclude: 1) implementation of a bioinformatics project within the biology curriculum provides a mechanism for successfully engaging large numbers of students in undergraduate research; 2) benefits to students are achievable at a wide variety of academic institutions; and 3) successful implementation of course-based research experiences requires significant investment of instructional time for students to gain full benefit.


Assuntos
Biologia/educação , Currículo , Pesquisa/educação , Atitude , Comportamento Cooperativo , Coleta de Dados , Docentes , Genoma , Genômica/educação , Humanos , Conhecimento , Aprendizagem , Anotação de Sequência Molecular , Avaliação de Programas e Projetos de Saúde , Pesquisadores , Autorrelato , Inquéritos e Questionários , Fatores de Tempo
7.
Biochem Mol Biol Educ ; 40(5): 310-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22987552

RESUMO

The development of fields such as bioinformatics and genomics has created new challenges and opportunities for undergraduate biology curricula. Students preparing for careers in science, technology, and medicine need more intensive study of bioinformatics and more sophisticated training in the mathematics on which this field is based. In this study, we deliberately integrated bioinformatics instruction at multiple course levels into an existing biology curriculum. Students in an introductory biology course, intermediate lab courses, and advanced project-oriented courses all participated in new course components designed to sequentially introduce bioinformatics skills and knowledge, as well as computational approaches that are common to many bioinformatics applications. In each course, bioinformatics learning was embedded in an existing disciplinary instructional sequence, as opposed to having a single course where all bioinformatics learning occurs. We designed direct and indirect assessment tools to follow student progress through the course sequence. Our data show significant gains in both student confidence and ability in bioinformatics during individual courses and as course level increases. Despite evidence of substantial student learning in both bioinformatics and mathematics, students were skeptical about the link between learning bioinformatics and learning mathematics. While our approach resulted in substantial learning gains, student "buy-in" and engagement might be better in longer project-based activities that demand application of skills to research problems. Nevertheless, in situations where a concentrated focus on project-oriented bioinformatics is not possible or desirable, our approach of integrating multiple smaller components into an existing curriculum provides an alternative.


Assuntos
Biologia/educação , Biologia Computacional/educação , Currículo , Matemática/educação , Avaliação Educacional , Humanos , Estudantes
8.
Planta ; 230(6): 1207-21, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19771450

RESUMO

A central question in biology is to understand how gene expression is precisely regulated to give rise to a variety of forms during the process of development. Epigenetic effects such as DNA methylation or histone modification have been increasingly shown to play a critical role in regulation of genome function. GCN5 is a prototypical histone acetyltransferase that participates in regulating developmental gene expression in several metazoan species. In Arabidopsis thaliana, plants with T-DNA insertions in GCN5 (also known as HAG1) display a variety of pleiotropic effects including dwarfism, loss of apical dominance, and floral defects affecting fertility. We sought to determine when during early development floral abnormalities first arise. Using scanning electron microscopy, we demonstrate that gcn5-1/hag1-1 and gcn5-5/hag1-5 mutants display overproliferation of young buds and development of abnormal structures around the inflorescence meristem. gcn5 mutants also display defects in stamen number and arrangement at later stages. This analysis provides temporal and spatial information to aid in the identification of GCN5 target genes in the developing flower. Preliminary studies of putative targets using reverse transcriptase PCR suggest that the floral meristem identity gene LEAFY is among factors upregulated in gcn5-1 mutants.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Flores/genética , Histona Acetiltransferases/genética , Meristema/genética , Arabidopsis/enzimologia , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/metabolismo , Flores/crescimento & desenvolvimento , Flores/ultraestrutura , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genótipo , Histona Acetiltransferases/metabolismo , Meristema/crescimento & desenvolvimento , Meristema/ultraestrutura , Microscopia Eletrônica de Varredura , Mutação , Fenótipo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
9.
Biochim Biophys Acta ; 1789(2): 117-24, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18929690

RESUMO

Histone acetylation is an example of covalent modification of chromatin structure that has the potential to regulate gene expression. Gcn5 is a prototypical histone acetyltransferase that associates with the transcriptional coactivator Ada2. In Arabidopsis, two genes encode proteins that resemble yeast ADA2 and share approximately 45% amino acid sequence identity. We previously reported that plants harboring a T-DNA insertion in the ADA2b gene display a dwarf phenotype with developmental defects in several organs. Here we describe T-DNA insertion alleles in the ADA2a gene, which result in no dramatic growth or developmental phenotype. Both ADA2a and ADA2b are expressed in a variety of plant tissues; moreover, expression of ADA2a from a constitutive promoter fails to complement the ada2b-1 mutant phenotype, consistent with the hypothesis that the two proteins have distinct biochemical roles. To further probe the cellular roles of ADA2a and ADA2b, we studied the response of the transcriptional coactivator mutants to abiotic stress. Although ada2b seedlings display hypersensitivity to salt and abscisic acid and altered responses to low temperature stress, the responses of ada2a seedlings to abiotic stress generally parallel those of wildtype plants. Intriguingly, ada2a;ada2b double mutant plants display an intermediate, gcn5-like phenotype, suggesting that ADA2a and ADA2b each work independently with GCN5 to affect genome function in Arabidopsis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Arabidopsis/metabolismo , Transativadores/fisiologia , Fatores de Transcrição/fisiologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/genética , DNA Bacteriano/genética , Congelamento , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Histona Acetiltransferases/fisiologia , Luz , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/efeitos da radiação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sais/farmacologia , Temperatura , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
10.
Biochem Mol Biol Educ ; 36(2): 159-65, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21591184

RESUMO

The importance of engaging students in science and helping them to become informed citizens has been highlighted by many groups invested in science education. This report describes a project that furthers both academic and civic goals through the integration of a service learning component into an undergraduate course. This nonmajors class covers the biology underlying the use of genetic information in today's society and provides students with the opportunity to discuss related ethical and political issues. The service learning project itself involved the creation of instructional materials dealing with the above topics and issues for use in local secondary school classrooms. Students developed materials in a digital media format to allow for revision in response to peer and community feedback. Outcomes of this pilot project suggest benefits to undergraduates as well as high school educators and students. Interdisciplinary collaborations and local educational partnerships have also been developed and strengthened through this work.

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