title: Planarians sense simulated microgravity and hypergravity.
abstract: Planarians are flatworms, which belong to the phylum Platyhelminthes. They have been a classical subject of study due to their amazing regenerative ability, which relies on the existence of adult totipotent stem cells. Nowadays they are an emerging model system in the field of developmental, regenerative, and stem cell biology. In this study we analyze the effect of a simulated microgravity and a hypergravity environment during the process of planarian regeneration and embryogenesis. We demonstrate that simulated microgravity by means of the random positioning machine (RPM) set at a speed of 60 °/s but not at 10 °/s produces the dead of planarians. Under hypergravity of 3 g and 4 g in a large diameter centrifuge (LDC) planarians can regenerate missing tissues, although a decrease in the proliferation rate is observed. Under 8 g hypergravity small planarian fragments are not able to regenerate. Moreover, we found an effect of gravity alterations in the rate of planarian scission, which is its asexual mode of reproduction. No apparent effects of altered gravity were found during the embryonic development.
authors.affiliation: Department of Genetics and Institute of Biomedicine, University of Barcelona, Catalonia, 08028 Barcelona, Spain.
authors.forename: Teresa
authors.initials: T
authors.lastname: Adell
authors.affiliation: Department of Genetics and Institute of Biomedicine, University of Barcelona, Catalonia, 08028 Barcelona, Spain.
authors.forename: Emili
authors.initials: E
authors.lastname: Saló
authors.affiliation: Dutch Experiment Support Center (DESC), Department of Oral and Maxillofacial Surgery/Oral Pathology, VU University Medical Center & Academic Centre for Dentistry Amsterdam (ACTA), Gustav Mahlerlaan 3004, 1081 LA Amsterdam, The Netherlands ; ESA-ESTEC, TEC-MMG, Keplerlaan 1, 2200 AG Noordwijk, The Netherlands.
authors.forename: Jack J W A
authors.initials: JJ
authors.lastname: van Loon
authors.affiliation: Pontifical Gregorian University, Piazza della Pilotta 4, 00187 Roma, Italy ; University of Cassino, Via Zamosch 43, 03043 Cassino, Italy.
authors.forename: Gennaro
authors.identifier: 0000-0001-6135-9779
authors.initials: G
authors.lastname: Auletta
mesh_terms: D000818:Animals; D004625:Embryo, Nonmammalian / Q000502:physiology; D006257:Head; D018471:Hypergravity; D010932:Planarians / Q000196:embryology / Q000502:physiology*; D012038:Regeneration / Q000502:physiology; D012100:Reproduction, Asexual / Q000502:physiology; D013623:Tail; D013997:Time Factors; D018474:Weightlessness Simulation