title: Microgravity effects on sea urchin fertilization and development.
abstract: Gravity has been a pervasive influence on all living systems and there is convincing evidence to suggest that it alters fertilization and embryogenesis in several developmental systems.  Notwithstanding the global importance of gravity on development, it has only been recently possible to begin to design experiments which might directly investigate the specific effects of this vector.  The goal of this research program is to explore and understand the effects of gravity on fertilization and early development using sea urchins as a model system.  Sea urchin development has several advantages for this project including the feasibility of maintaining and manipulating these cells during spaceflight, the high percentage of normal fertilization and early development, and the abundant knowledge about molecular, biochemical, and cellular events during embryogenesis which permits detailed insights into the mechanism by which gravity might interfere with development.  Furthermore, skeletal calcium is deposited into the embryonic spicules within a day of fertilization permitting studies of the effects of gravity on bone calcium deposition.
authors.affiliation: Department of Zoology and Integrated Microscopy Resource, University of Wisconsin, Madison 53706, USA.
authors.forename: S
authors.initials: S
authors.lastname: Steffen
authors.forename: R
authors.initials: R
authors.lastname: Fiser
authors.forename: C
authors.initials: C
authors.lastname: Simerly
authors.forename: H
authors.initials: H
authors.lastname: Schatten
authors.forename: G
authors.initials: G
authors.lastname: Schatten
mesh_terms: D000818:Animals; D002455:Cell Division; D004867:Equipment Design; D005260:Female; D005306:Fertilization / Q000502:physiology*; D018466:Gravity Sensing; D006799:Housing, Animal; D008297:Male; D010063:Ovum; D012617:Sea Urchins / Q000196:embryology* / Q000254:growth & development*; D013026:Space Flight / Q000295:instrumentation*; D013094:Spermatozoa; D014893:Weightlessness