Painted turtles are remarkable for their freeze tolerance and supercooling ability along with their associated resilience to hypoxia/anoxia and oxidative stress, rendering them an ideal biomedical model for hypoxia-induced injuries (including strokes), tissue cooling during surgeries, and organ cryopreservation. Yet, such research is hindered by their seasonal reproduction and slow maturation. Here we developed and characterized adult stem cell-derived turtle liver organoids (3D self-assembled in vitro structures) from painted, snapping, and spiny softshell turtles spanning ~175My of evolution, with a subset cryopreserved.
View Article and Find Full Text PDFIn some turtle species, temperature selection may be influenced by environmental conditions, including acclimation temperature and substrate quality. These factors may be particularly important for softshell turtles that are highly aquatic and often thermoregulate by burying in the substrate in shallow water microhabitats. We tested for effects of acclimation temperature (22 °C or 27 °C) and substrate type (sand or gravel) on the selected temperature and movement patterns of 20 juvenile spiny softhshell turtles (Apalone spinifera; Reptilia: Trionychidae) in an aquatic thermal gradient of 14-34 °C.
View Article and Find Full Text PDFIn reptiles, sex-determining mechanisms have evolved repeatedly and reversibly between genotypic and temperature-dependent sex determination. The gene Dmrt1 directs male determination in chicken (and presumably other birds), and regulates sex differentiation in animals as distantly related as fruit flies, nematodes and humans. Here, we show a consistent molecular difference in Dmrt1 between reptiles with genotypic and temperature-dependent sex determination.
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