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1.
Artigo em Inglês | MEDLINE | ID: mdl-38770402

RESUMO

The genus Magicicada (Hemiptera: Cicadidae) includes the periodical cicadas of Eastern North America. Spending the majority of their long lives underground, the adult cicadas emerge every 13 or 17 years to spend 4-6 weeks as adult to mate. We present the whole genome sequences of two species of 17-year cicadas, Magicicada septendecim and Magicicada septendecula. The reads were assembled by a de novo method followed by alignments to related species. Annotation was performed by GeneMark-ES. The raw and assembled data is available via NCBI Short Read Archive and Assembly databases.

2.
BMC Genomics ; 19(1): 695, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30241500

RESUMO

BACKGROUND: Although hatching is perhaps the most abrupt and profound metabolic challenge that a chicken must undergo; there have been no attempts to functionally map the metabolic pathways induced in liver during the embryo-to-hatchling transition. Furthermore, we know very little about the metabolic and regulatory factors that regulate lipid metabolism in late embryos or newly-hatched chicks. In the present study, we examined hepatic transcriptomes of 12 embryos and 12 hatchling chicks during the peri-hatch period-or the metabolic switch from chorioallantoic to pulmonary respiration. RESULTS: Initial hierarchical clustering revealed two distinct, albeit opposing, patterns of hepatic gene expression. Cluster A genes are largely lipolytic and highly expressed in embryos. While, Cluster B genes are lipogenic/thermogenic and mainly controlled by the lipogenic transcription factor THRSPA. Using pairwise comparisons of embryo and hatchling ages, we found 1272 genes that were differentially expressed between embryos and hatchling chicks, including 24 transcription factors and 284 genes that regulate lipid metabolism. The three most differentially-expressed transcripts found in liver of embryos were MOGAT1, DIO3 and PDK4, whereas THRSPA, FASN and DIO2 were highest in hatchlings. An unusual finding was the "ectopic" and extremely high differentially expression of seven feather keratin transcripts in liver of 16 day embryos, which coincides with engorgement of liver with yolk lipids. Gene interaction networks show several transcription factors, transcriptional co-activators/co-inhibitors and their downstream genes that exert a 'ying-yang' action on lipid metabolism during the embryo-to-hatching transition. These upstream regulators include ligand-activated transcription factors, sirtuins and Kruppel-like factors. CONCLUSIONS: Our genome-wide transcriptional analysis has greatly expanded the hepatic repertoire of regulatory and metabolic genes involved in the embryo-to-hatchling transition. New knowledge was gained on interactive transcriptional networks and metabolic pathways that enable the abrupt switch from ectothermy (embryo) to endothermy (hatchling) in the chicken. Several transcription factors and their coactivators/co-inhibitors appear to exert opposing actions on lipid metabolism, leading to the predominance of lipolysis in embryos and lipogenesis in hatchlings. Our analysis of hepatic transcriptomes has enabled discovery of opposing, interconnected and interdependent transcriptional regulators that provide precise ying-yang or homeorhetic regulation of lipid metabolism during the critical embryo-to-hatchling transition.


Assuntos
Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Fígado/metabolismo , Animais , Cruzamento , Embrião de Galinha/crescimento & desenvolvimento , Embrião de Galinha/metabolismo , Desenvolvimento Embrionário , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Fígado/embriologia , Fígado/crescimento & desenvolvimento , Transcriptoma
3.
BMC Genomics ; 19(1): 177, 2018 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-29506485

RESUMO

BACKGROUND: A strain of Leghorn chickens (rd/rd), unable to produce a functional riboflavin-binding protein, lays riboflavin-deficient eggs, in which all embryos suddenly die at mid-incubation (days 13-15). This malady, caused by riboflavin deficiency, leads to excessive lipid accumulation in liver, impaired ß-oxidation of lipid, and severe hypoglycemia prior to death. We have used high-density chicken microarrays for time-course transcriptional scans of liver in chicken embryos between days 9-15 during this riboflavin-deficiency-induced metabolic catastrophe. For comparison, half of rd/rd embryos (n = 16) were rescued from this calamity by injection of riboflavin just prior to incubation of fertile eggs from rd/rd hens. RESULTS: No significant differences were found between hepatic transcriptomes of riboflavin-deficient and riboflavin-rescued embryos at the first two ages (days 9 and 11). Overall, we found a 3.2-fold increase in the number of differentially expressed hepatic genes between day 13 (231 genes) and day 15 (734 genes). Higher expression of genes encoding the chicken flavoproteome was more evident in rescued- (15 genes) than in deficient-embryos (4 genes) at day 15. Diminished activity of flavin-dependent enzymes in riboflavin-deficient embryos blocks catabolism of yolk lipids, which normally serves as the predominant source of energy required for embryonic development. CONCLUSIONS: Riboflavin deficiency in mid-stage embryos leads to reduced expression of numerous genes controlling critical functions, including ß-oxidation of lipids, blood coagulation and feathering. Surprisingly, reduced expression of feather keratin 1 was found in liver of riboflavin-deficient embryos at e15, which could be related to their delayed feathering and sparse clubbed down. A large number of genes are expressed at higher levels in liver of riboflavin-deficient embryos; these up-regulated genes control lipid storage/transport, gluconeogenesis, ketogenesis, protein catabolism/ubiquitination and cell death.


Assuntos
Galinhas , Plumas/crescimento & desenvolvimento , Fígado/patologia , Doenças das Aves Domésticas/genética , Deficiência de Riboflavina/genética , Deficiência de Riboflavina/veterinária , Animais , Embrião de Galinha , Metabolismo Energético , Plumas/metabolismo , Hemorragia/genética , Hemorragia/patologia , Hemorragia/veterinária , Lipídeos/genética , Fígado/metabolismo , Doenças das Aves Domésticas/metabolismo , Doenças das Aves Domésticas/patologia , Riboflavina/metabolismo , Deficiência de Riboflavina/metabolismo , Deficiência de Riboflavina/patologia
4.
Biochem Mol Biol Educ ; 43(5): 345-57, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26373243

RESUMO

There are barriers to adoption of research-based teaching methods. Professional development workshops may inform faculty of these methods, but effective adoption often does not follow. In addition, newly-minted research-active faculty are often overwhelmed by the many new responsibilities (grant writing, group management, laboratory setup, teaching) that accompany the position and normally do not have the time to consider novel teaching approaches. This case study documents how over a three-year period, the responsibility for teaching a nontraditional "Introduction to Biochemistry" course in a problem-based learning format was successfully transferred from a senior faculty member nearing retirement (HBW) to a newly-hired research-active assistant professor (CLG). We describe our apprenticeship project involving modeling, scaffolding, fading, and coaching. We suggest that involving faculty in active-learning pedagogy early in their career with mentoring by senior faculty overcomes barriers to adopting these methods. This case describes a specific example from which potentially useful elements can be adopted and adapted wherever biochemistry is taught.


Assuntos
Mentores , Aprendizagem Baseada em Problemas/métodos , Pesquisa/educação , Ensino/métodos , Docentes , Humanos , Aprendizagem
5.
Biochem Mol Biol Educ ; 43(5): 341-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26153350

RESUMO

Undergraduates having their first research experience frequently have little idea of what to expect. Institutions offering summer research experiences attempt to address this issue through programs that introduce students to the process and culture of science. However, didactic approaches frequently bore students who prefer more interactive sessions. We describe a "Pass-the-Problem" case study approach that engages groups of students in useful discussions about the research environment they are entering. The cases presented here include keeping a thorough laboratory notebook, balancing laboratory and personal time demands, anxiety about formal presentations, unexpected federal regulatory inspection, working in a lab with limited funds, being used as a technician rather than a researcher, frustration with failed experiments, effects of promotion and tenure on laboratory atmosphere, the importance of reading the research literature, and questioning a career in science. These cases alert students to different situations they might encounter and stimulate discussion about how to deal with them.


Assuntos
Educação/métodos , Aprendizagem Baseada em Problemas/métodos , Pesquisa/educação , Ciência/educação , Humanos , Pesquisadores , Estudantes
8.
Biochem Mol Biol Educ ; 41(5): 297-301, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24019246

RESUMO

Biochemistry and molecular biology (BMB) students should demonstrate proficiency in the foundational concepts of the discipline and possess the skills needed to practice as professionals. To ascertain the skills that should be required, groups of BMB educators met in several focused workshops to discuss the expectations with the ultimate goal of clearly articulating the skills required. The results of these discussions highlight the critical importance of experimental, mathematical, and interpersonal skills including collaboration, teamwork, safety, and ethics. The groups also found experimental design, data interpretation and analysiand the ability to communicate findings to diverse audience to be essential skills. To aid in the development of appropriate assessments these skills are grouped into three categories, 1) Process of Science, 2) Communication and Comprehension of Science, and 3) Community of Practice Aspects of Science. Finally, the groups worked to align these competencies with the best practices in both teaching and in skills assessment.


Assuntos
Bioquímica/educação , Objetivos , Aprendizagem , Biologia Molecular/educação , Estudantes/psicologia , Universidades , Avaliação Educacional
12.
CBE Life Sci Educ ; 9(3): 181-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20810949

RESUMO

The BIO2010 report recommended that students in the life sciences receive a more rigorous education in mathematics and physical sciences. The University of Delaware approached this problem by (1) developing a bio-calculus section of a standard calculus course, (2) embedding quantitative activities into existing biology courses, and (3) creating a new interdisciplinary major, quantitative biology, designed for students interested in solving complex biological problems using advanced mathematical approaches. To develop the bio-calculus sections, the Department of Mathematical Sciences revised its three-semester calculus sequence to include differential equations in the first semester and, rather than using examples traditionally drawn from application domains that are most relevant to engineers, drew models and examples heavily from the life sciences. The curriculum of the B.S. degree in Quantitative Biology was designed to provide students with a solid foundation in biology, chemistry, and mathematics, with an emphasis on preparation for research careers in life sciences. Students in the program take core courses from biology, chemistry, and physics, though mathematics, as the cornerstone of all quantitative sciences, is given particular prominence. Seminars and a capstone course stress how the interplay of mathematics and biology can be used to explain complex biological systems. To initiate these academic changes required the identification of barriers and the implementation of solutions.


Assuntos
Biologia/educação , Matemática/educação , Modelos Educacionais , Estudantes , Universidades , Currículo
13.
Biochem Mol Biol Educ ; 38(1): 35-6, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21567788
14.
Biochem Mol Biol Educ ; 38(2): 116, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21567806
16.
Biochem Mol Biol Educ ; 38(6): 408-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21567870
17.
Biochem Mol Biol Educ ; 37(1): 56-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21567689
18.
Biochem Mol Biol Educ ; 37(2): 116-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21567716
19.
Biochem Mol Biol Educ ; 37(3): 186-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-21567730
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