Graded FGF activity patterns distinct cell types within the apical sensory organ of the sea anemone Nematostella vectensis.

Bilaterian animals have evolved complex sensory organs comprised of distinct cell types that function coordinately to sense the environment. Each sensory unit has a defined architecture built from component cell types, including sensory cells, non-sensory support cells, and dedicated sensory neurons. Whether this characteristic cellular composition is present in the sensory organs of non-bilaterian animals is unknown. Here, we interrogate the cell type composition and gene regulatory networks controlling development of the larval apical sensory organ in the sea anemone Nematostella vectensis. Using single cell RNA sequencing and imaging approaches, we reveal two unique cell types in the Nematostella apical sensory organ, GABAergic sensory cells and a putative non-sensory support cell population. Further, we identify the paired-like (PRD) homeodomain gene prd146 as a specific sensory cell marker and show that Prd146+ sensory cells become post-mitotic after gastrulation. Genetic loss of function approaches show that Prd146 is essential for apical sensory organ development. Using a candidate gene knockdown approach, we place prd146 downstream of FGF signaling in the apical sensory organ gene regulatory network. Further, we demonstrate that an aboral FGF activity gradient coordinately regulates the specification of both sensory and support cells. Collectively, these experiments define the genetic basis for apical sensory organ development in a non-bilaterian animal and reveal an unanticipated degree of complexity in a prototypic sensory structure.

An Inorganic Chemistry Laboratory Technique Course using Scaffolded, Inquiry-Based Laboratories and Project-Based Learning.

To enhance students' learning and help them understand the whole picture of the field of inorganic chemistry, an inorganic laboratory technique course was designed that uses scaffolded, inquiry-based lab experiments and project-based learning. The scaffolded, inquiry-based laboratories taught in the first 8 weeks of the course helped students better understand the aim of each lab and how to apply each lab technique to a bigger research project. The laboratory experiments also included opportunities for cooperative and collaborative learning through student group work and feedback. To further develop students' independent research skills, we implemented project-based learning in the second part of the course (last 4 weeks), in which students develop a research proposal based on independent literature research and the laboratory techniques they learned from the course. Pilot data suggest that the course helped improve students' interest in inorganic chemistry, science self-efficacy, and science identity. Additionally, students reported that both the scaffolded, inquiry-based laboratories and the project-based learning module enhanced their problem-solving and critical thinking skills.