The tuberal hypothalamus harbours clinically important neuronal and glial populations with central roles in energy homeostasis. Previous work has revealed key roles for SHH and BMP signalling in tuberal progenitor specification, and suggested that dynamic BMP signalling specifies tuberal hypothalamic progenitors from hypothalamic floor plate-like (HypFP) cells in an anterior (neurogenic) to posterior (gliogenic) sequence. Here, through gain- and loss-of-function studies in vivo and ex vivo, we provide evidence that FGF10, which is induced by BMP signalling, operates with SHH and BMP to contribute to neurogenic and gliogenic fates. Our results indicate that SHH levels must be finely-tuned to support sustained tuberal neurogenesis, and are consistent with a model in which transient BMP/FGF10 signalling activity in anterior-most HypFP cells reduces SHH expression, in a manner that optimises tuberal neurogenic specification rate during a critical developmental period, while sustained BMP/FGF10 signalling activity in mid-HypFP cells promotes tuberal gliogenic fate.

BioEYES is a K-12 life science outreach program that uses zebrafish to teach Mendelian genetics through hands-on activities. The program has operated for 20+ years, promoting academic equity and fostering scientific literacy for all students. While middle school participants show knowledge gains and improved attitudes about science, ∼50% struggle to master foundational genetic concepts. To address this, the authors compared virtual vs. in-person programming, finding minimal differences in learning outcomes but higher gains on simpler survey questions. Rigorous assessments, however, reveal that many students retain only a basic understanding of genetics. Teaching single-gene inheritance, moreover, may reinforce racial stereotypes through "biological essentialism." To counter this, BioEYES staff will be piloting approaches that focus on human polygenic traits, such as skin color, that is taught alongside a hands-on experiment with a zebrafish pigment mutant. Future efforts emphasize developing curriculum around polygenic traits, gene-environment interactions, and challenging stereotypes about race, which research suggests could improve genetics comprehension while reducing racial stereotyping. We invite community feedback in these efforts to enhance K-12 genetics education strategies.

Extraembryonic tissues are essential for proper fetal development and exhibit great diversity across species. Despite its importance, human extraembryonic development has been relatively overlooked. Previously, we established an in vitro model to study human amniogenesis and extraembryonic mesoderm formation. In this article, I develop discussions on four topics inspired by this study: (1) Features of amniotic cell populations described to date. A recently reported early amniotic cell type is examined based on its signature genes to consider how this population should be incorporated into models of primate amniogenesis. (2) Molecular mechanisms underlying the effect of cell density in regulating non-neural ectoderm specification. Fate specification by positional cues in mouse is revisited and possible mechanisms are suggested by drawing insights from human epiblast models. (3) Potential applications of the three-dimensional culture we established. Primate amniotic ectoderm is postulated as a gastrulation-inducing signaling center, and our technique could be used to effectively model its interactions with epiblast. (4) Extraembryonic mesoderm development in human embryos. The obscure origin of primate extraembryonic mesoderm and implications from recent in vitro differentiation models using human pluripotent stem cells are explained. The key concepts explored here will stimulate further studies into both amnion and extraembryonic mesoderm during human and non-human primate development.