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The use of CRISPR-based experiments in an undergraduate course is appealing because of the ease of editing, and the relevance of CRISPR to current research. Before the COVID-19 pandemic, we developed an in-person lab for a high-enrollment course that allowed students to design and conduct CRISPR editing experiments in budding yeast, Saccharomyces cerevisiae. Post pandemic, the lab course moved online, and we lost the hands-on component. We subsequently developed an at-home kit that contained all the necessary materials for students to grow and transform S. cerevisiae with the DNA molecules necessary for CRISPR-Cas9 induced editing. Our at-home kits cost approximately $70 each to produce and were shipped to over 600 students during the 2020 to 2021 academic year. By adding the at-home experimental work to our remote, online lab course, students were able to generate loss-of-function mutants in ADE2 (causing a red color phenotype). Students were able to send edited yeast samples back to campus for sequencing, allowing for characterization of the different mutations that can occur due to CRISPR-Cas9 induced editing. Here, we described the protocol to produce and use the kits and summarized the student experience of using the at-home kit in a large enrollment, remote lab course. These kits provided opportunities to engage students in hands-on experimentation during a remote course and could also be used to reach learners in other domains, such as high schools and outreach programs.

In many of our courses, particularly laboratory courses, students are expected to engage in scientific writing. Despite various efforts by other courses and library resources, as instructors we are often faced with the frustration of student plagiarism and related writing problems. Here, we describe a simple Writing in Your Own Voice intervention designed to help students become more aware of different types of plagiarism and writing problems, avoid those problems, and practice writing in their own voice. In this article, we will introduce the types of plagiarism and writing problems commonly encountered in our molecular biology laboratory course, the intervention, and the results of our study. From the evaluation of 365 student reports, we found the intervention resulted in nearly 50% fewer instances of plagiarism and common writing problems. We also observed significantly fewer instances of severe plagiarism (e.g. several sentences copied from an external source). In addition, we find that the effects last for several weeks after the students complete the intervention assignment. This assignment is particularly easy to implement and can be a very useful tool for teaching students how to write in their own voices. © 2019 International Union of Biochemistry and Molecular Biology, 47(5):589-598, 2019.

A growing body of evidence has shown that active learning has a considerable advantage over traditional lecture for student learning in undergraduate STEM classes, but there have been few large-scale studies to identify the specific types of activities that have the greatest impact on learning. We therefore undertook a large-scale, curriculum-wide study to investigate the effects of time spent on a variety of classroom activities on learning gains. We quantified classroom practices and related these to student learning, assessed using diagnostic tests written by over 3700 students, across 31 undergraduate biology classes at a research-intensive university in the Pacific Northwest. The most significant positive predictor of learning gains was the use of group work, supporting the findings of previous studies. Strikingly, we found that the addition of worksheets as an active learning tool for in-class group activities had the strongest impact on diagnostic test scores. This particular low-tech activity promotes student collaboration, develops problem solving skills, and can be used to inform the instructor about what students are struggling with, thus providing opportunities for valuable and timely feedback. Overall, our results indicate that group activities with low barriers to entry, such as worksheets, can result in significant learning gains in undergraduate science.

Understanding the cellular properties controlling neural stem and progenitor cell (NSPC) fate choice will improve their therapeutic potential. The electrophysiological measure whole-cell membrane capacitance reflects fate bias in the neural lineage but the cellular properties underlying membrane capacitance are poorly understood. We tested the hypothesis that cell surface carbohydrates contribute to NSPC membrane capacitance and fate. We found NSPCs differing in fate potential express distinct patterns of glycosylation enzymes. Screening several glycosylation pathways revealed that the one forming highly branched N-glycans differs between neurogenic and astrogenic populations of cells in vitro and in vivo. Enhancing highly branched N-glycans on NSPCs significantly increases membrane capacitance and leads to the generation of more astrocytes at the expense of neurons with no effect on cell size, viability, or proliferation. These data identify the N-glycan branching pathway as a significant regulator of membrane capacitance and fate choice in the neural lineage.

The excessive "jargon" load in biology may be a hurdle for developing conceptual understanding as well as achieving core competencies such as scientific literacy and communication. Little work has been done to characterize student understanding of biology-specific jargon. To address this issue, we aimed to determine the types of biology jargon terms that students struggle with most, the alignment between students' perceived understanding and performance defining the terms, and common errors in student-provided definitions. Students in two biology classes were asked to report their understanding of, and provide definitions for, course-specific vocabulary terms: 1276 student responses to 72 terms were analyzed. Generally, students showed an overestimation of their own understanding. The least accurate self-assessment occurred for terms to which students had substantial prior exposure and terms with discordant meanings in biology versus everyday language. Students were more accurate when assessing their understanding of terms describing abstract molecular structures, and these were often perceived as more difficult than other types of terms. This research provides insights about which types of technical vocabulary may create a barrier to developing deeper conceptual understanding, and highlights a need to consider student understanding of different types of jargon in supporting learning and scientific literacy.

Neural stem and progenitor cell (NSPC) fate is strongly influenced by mechanotransduction as modulation of substrate stiffness affects lineage choice. Other types of mechanical stimuli, such as stretch (tensile strain), occur during CNS development and trauma, but their consequences for NSPC differentiation have not been reported. We delivered a 10% static equibiaxial stretch to NSPCs and examined effects on differentiation. We found static stretch specifically impacts NSPC differentiation into oligodendrocytes, but not neurons or astrocytes, and this effect is dependent on particular extracellular matrix (ECM)-integrin linkages. Generation of oligodendrocytes from NSPCs was reduced on laminin, an outcome likely mediated by the α6 laminin-binding integrin, whereas similar effects were not observed for NSPCs on fibronectin. Our data demonstrate a direct role for tensile strain in dictating the lineage choice of NSPCs and indicate the dependence of this phenomenon on specific substrate materials, which should be taken into account for the design of biomaterials for NSPC transplantation.

Dielectrophoresis (DEP) has proven an invaluable tool for the enrichment of populations of stem and progenitor cells owing to its ability to sort cells in a label-free manner and its biological safety. However, DEP separation devices have suffered from a low throughput preventing researchers from undertaking studies requiring large numbers of cells, such as needed for cell transplantation. We developed a microfluidic device designed for the enrichment of stem and progenitor cell populations that sorts cells at a rate of 150,000 cells/h, corresponding to an improvement in the throughput achieved with our previous device designs by over an order of magnitude. This advancement, coupled with data showing the DEP-sorted cells retain their enrichment and differentiation capacity when expanded in culture for periods of up to 2 weeks, provides sufficient throughput and cell numbers to enable a wider variety of experiments with enriched stem and progenitor cell populations. Furthermore, the sorting devices presented here provide ease of setup and operation, a simple fabrication process, and a low associated cost to use that makes them more amenable for use in common biological research laboratories. To our knowledge, this work represents the first to enrich stem cells and expand them in culture to generate transplantation-scale numbers of differentiation-competent cells using DEP.

Postdoctoral positions in biology education research (BER) are becoming increasingly common as the field grows. However, many life science graduate students are unaware of these positions or do not understand what these positions entail or the careers with which they align. In this essay, we use a backward-design approach to inform life science graduate students of postdoctoral opportunities in BER. Beginning with the end in mind, we first discuss the types of careers to which BER postdoctoral positions lead. We then discuss the different types of BER postdoctoral positions, drawing on our own experiences and those of faculty mentors. Finally, we discuss activities in which life science graduate students can engage that will help them gauge whether BER aligns with their research interests and develop skills to be competitive for BER postdoctoral positions.

An essential component skill of monitoring and reflection during problem solving is work checking, a process used by experts while solving problems to determine if their solution is achieving the goal. The results of work checking may reveal errors or inconsistencies, indicating a need for iteration. Using think-aloud interviews, the authors identified that most students in our undergraduate genetics course did not engage in checking while solving problems. In response, the authors made changes to the course curriculum to include explicit teaching of work checking, practice and feedback on work checking, and allotting a small number of course points for demonstration of checking on quizzes and exams.

In this experiment, students in a large undergraduate biology course were first exposed to the concepts without new technical vocabulary ("jargon") in a pre-class reading assignment. Their learning of the concepts and jargon was compared with that of an equivalent group of students in another section of the same course, whose pre-class reading presented both the jargon and concepts together in the traditional manner. Both groups had the same active-learning classes with the same instructor, and then completed the same post-test. Although the two groups performed the same on the multiple choice questions of the post-test, the group exposed to concepts first and jargon second included 1.5 times and 2.5 times more correct arguments on two free-response questions about the concepts. The correct use of jargon between the two groups was similar, with the exception of one jargon term that the control group used more often. These results suggest that modest instructional changes whereby new concepts are introduced in a concepts-first, jargon-second manner can increase student learning, as demonstrated by their ability to articulate their understanding of new concepts.