The embryo of the laboratory opossum, Monodelphis domestica, offers unprecedented opportunities for investigating certain poorly understood aspects of embryonic development in mammals. Unlike mouse embryos, in which mammalian development has been conventionally studied, the opossum embryo is much larger, implants long after organogenesis has begun, but is born in a comparatively undeveloped state. Like other marsupial embryos, those of the opossum contain yolk, possess extracellular investments, require the zona pellucida for blastocyst formation, and form a yolk-sac placenta. Dr. Cruz will investigate how marsupial embryos undergo axis formation, blastulation, and gastrulation to obtain information regarding the morphogenetic and evolutionary differences and similarities between the embryos of marsupial and so-called placental mammals. She will take advantage of the recent sequencing of the opossum genome to identify genes with conserved or novel functions in mammalian embryogenesis. In addition, the PI has a second objective: the research training of undergraduate students in biological research, an activity in which Oberlin College has traditionally excelled since its founding in 1833. The twin goals of the proposed study are 1) to sharpen and expand our knowledge of mammalian evolution in general and developmental biology in particular and 2) ensure that the acquisition of scientific knowledge by students is imbued with the joy of discovery made possible only by hands-on involvement.
