RESUMEN
Social media offers potential for educator professional learning, but platforms' for-profit nature complicates this practice, especially for professional learning around justice-oriented pedagogies. This exploratory study investigated 551 publicly available Instagram posts shared by 11 purposefully sampled, justice-oriented education influencers over an 8-week period as the COVID-19 pandemic and renewed activism for racial justice unfolded in the United States. Qualitative analysis of post content indicated these influencers offered pandemic-related support, while also illustrating, enacting, and engaging culturally relevant and sustaining pedagogies. However, promotional content was abundantly layered within posts and a cohesive message of how to enact culturally sustaining pedagogies was largely absent. Reflecting some of the paradoxes of learning via social media, our findings suggest there is some opportunity for justice-oriented professional learning from social media, however education influencers' content is limited by platforms' opaque algorithms and for-profit business models, which govern what influencers post and what followers see.
RESUMEN
Genomics is not only essential for students to understand biology but also provides unprecedented opportunities for undergraduate research. The goal of the Genomics Education Partnership (GEP), a collaboration between a growing number of colleges and universities around the country and the Department of Biology and Genome Center of Washington University in St. Louis, is to provide such research opportunities. Using a versatile curriculum that has been adapted to many different class settings, GEP undergraduates undertake projects to bring draft-quality genomic sequence up to high quality and/or participate in the annotation of these sequences. GEP undergraduates have improved more than 2 million bases of draft genomic sequence from several species of Drosophila and have produced hundreds of gene models using evidence-based manual annotation. Students appreciate their ability to make a contribution to ongoing research, and report increased independence and a more active learning approach after participation in GEP projects. They show knowledge gains on pre- and postcourse quizzes about genes and genomes and in bioinformatic analysis. Participating faculty also report professional gains, increased access to genomics-related technology, and an overall positive experience. We have found that using a genomics research project as the core of a laboratory course is rewarding for both faculty and students.
Asunto(s)
Investigación Genética , Genómica/educación , Laboratorios , Universidades , Animales , Docentes , Estudiantes/psicologíaRESUMEN
We report that under 'transcriptional stress' in budding yeast, when most pol II activity is acutely inhibited, rapid deposition of nucleosomes occurs within genes, particularly at 3' positions. Whereas histone H3K4 trimethylation normally marks 5' ends of highly transcribed genes, under 'transcriptional stress' induced by 6-azauracil (6-AU) and inactivation of pol II, TFIIE or CTD kinases Kin28 and Ctk1, this mark shifted to the 3' end of the TEF1 gene. H3K4Me3 at 3' positions was dynamic and could be rapidly removed when transcription recovered. Set1 and Chd1 are required for H3K4 trimethylation at 3' positions when transcription is inhibited by 6-AU. Furthermore, Deltachd1 suppressed the growth defect of Deltaset1. We suggest that a 'transcriptional stress' signal sensed through Set1, Chd1, and possibly other factors, causes H3K4 hypermethylation of newly deposited nucleosomes at downstream positions within a gene. This response identifies a new role for H3K4 trimethylation at the 3' end of the gene, as a chromatin mark associated with impaired pol II transcription.
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Cromatina/metabolismo , ADN Polimerasa II/metabolismo , Histonas/metabolismo , Nucleosomas/metabolismo , Saccharomyces cerevisiae/metabolismo , Transcripción Genética , ADN Polimerasa II/genética , Proteínas de Unión al ADN/metabolismo , N-Metiltransferasa de Histona-Lisina , Metilación , Mutación , Proteínas Quinasas/metabolismo , Estructura Terciaria de Proteína , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transducción de Señal , Factores de Transcripción/metabolismo , Factores de Transcripción TFII/metabolismo , Uracilo/análogos & derivadosRESUMEN
Capping enzymes bind the phosphorylated pol II CTD permitting cotranscriptional capping of nascent pre-mRNAs. We asked whether these interactions influence pol II function using ChIP in ts mutants of yeast capping enzymes. Pol II occupancy at the 5' ends of PGK1, ENO2, GAL1, and GAL10 was reduced by inactivation of the methyltransferase, Abd1, but not the guanylyltransferase, Ceg1, suggesting that Abd1 contributes to stable promoter binding. At other genes, Abd1 inactivation increased the 5':3' ratio of pol II density in the promoter-proximal region and caused Ser5 hyperphosphorylation of the pol II CTD. These results suggest an additional role for Abd1 in the promoter clearance and/or promoter-proximal elongation steps of transcription. The transcriptional functions of Abd1 are independent of methyltransferase activity. Manipulation of transcription by Abd1 may enhance cotranscriptional capping and also act as a checkpoint to ensure that a nascent transcript has a cap before it can be completed.
Asunto(s)
Genes Reguladores/genética , Metiltransferasas/metabolismo , Proteínas de Unión a Caperuzas de ARN/metabolismo , ARN Polimerasa II/metabolismo , ARN Mensajero/metabolismo , Sitios de Unión/genética , Células Cultivadas , Regulación Enzimológica de la Expresión Génica/genética , Regulación Fúngica de la Expresión Génica/genética , Genes cdc/fisiología , Metiltransferasas/genética , Mutación/genética , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Regiones Promotoras Genéticas/genética , Unión Proteica/genética , Proteínas de Unión a Caperuzas de ARN/genética , ARN Polimerasa II/genética , Transcripción Genética/genética , LevadurasRESUMEN
The RNA polymerase II CTD is essential for 3' end cleavage of metazoan pre-mRNAs and binds 3' end processing factors in vitro. We show genetic and biochemical interactions between the CTD and the Pcf11 subunit of the yeast cleavage/polyadenylation factor, CFIA. In vitro binding to Pcf11 required phosphorylation of the CTD on Ser2 in the YSPTSPS heptad repeats. Deletion of the yeast CTD reduced the efficiency of cleavage at poly(A) sites, and the length of poly(A) tails suggesting that it helps couple 3' end formation with transcription. Consistent with this model, the 3' end processing factors CFIA, CFIB, and PFI were recruited to genes progressively, starting at the 5' end, in a process that required ongoing transcription.