ABSTRACT
With a primary objective to engage students in the process of science online, we transformed a long-standing laboratory course for first-year science students into a more accessible, immersive experience of current biological research using a narrow and focused set of primary literature and the Consider, Read, Elucidate a hypothesis, Analyze and interpret data, Think of the next Experiment (CREATE) pedagogy. The efficacy of the CREATE approach has been demonstrated in a diversity of higher education settings and courses. It is, however, not yet known if CREATE can be successfully implemented online with a large, diverse team of faculty untrained in the CREATE pedagogy. Here, we present the transformation of a large-enrollment, multi-section, multi-instructor course for first-year students in which the instructors follow different biological research questions but work together to reach shared goals and outcomes. We assessed students' (i) science self-efficacy and (ii) epistemological beliefs about science throughout an academic year of instruction fully administered online as a result of ongoing threats posed by COVID-19. Our findings demonstrate that novice CREATE instructors with varying levels of teaching experience and ranks can achieve comparable outcomes and improvements in students' science efficacy in the virtual classroom as a teaching team. This study extends the use of the CREATE pedagogy to large, team-taught, multi-section courses and shows its utility in the online teaching and learning environment.
ABSTRACT
The plant cell wall is a highly dynamic structure that changes in response to both environmental and developmental cues. It plays important roles throughout plant growth and development in determining the orientation and extent of cell expansion, providing structural support and acting as a barrier to pathogens. Despite the importance of the cell wall, the signaling pathways regulating its function are not well understood. Two partially redundant leucine-rich-repeat receptor-like kinases (LRR-RLKs), FEI1 and FEI2, regulate cell wall function in Arabidopsis thaliana roots; disruption of the FEIs results in short, swollen roots as a result of decreased cellulose synthesis. We screened for suppressors of this swollen root phenotype and identified two mutations in the putative mitochondrial pyruvate dehydrogenase E1α homolog, IAA-Alanine Resistant 4 (IAR4). Mutations in IAR4 were shown previously to disrupt auxin homeostasis and lead to reduced auxin function. We show that mutations in IAR4 suppress a subset of the fei1 fei2 phenotypes. Consistent with the hypothesis that the suppression of fei1 fei2 by iar4 is the result of reduced auxin function, disruption of the WEI8 and TAR2 genes, which decreases auxin biosynthesis, also suppresses fei1 fei2. In addition, iar4 suppresses the root swelling and accumulation of ectopic lignin phenotypes of other cell wall mutants, including procuste and cobra. Further, iar4 mutants display decreased sensitivity to the cellulose biosynthesis inhibitor isoxaben. These results establish a role for IAR4 in the regulation of cell wall function and provide evidence of crosstalk between the cell wall and auxin during cell expansion in the root.
