June 3, 2021

5:00pm Zoom

EcoEvoPub Seminar Series
Department of Ecology and Evolutionary Biology, UCLA

" Graduate Student Presentations "

Clive Lau

Department of Ecology and Evolutionary Biology, UCLA, Sears Lab

“Progress in generating the first transgenic marsupial model”

As the sister clade to placental mammals, marsupials occupy a unique position on the phylogeny for the study of mammalian evolution. When it comes to understanding development, transgenic animals have long been an invaluable asset, but to date no transgenic marsupials have been generated, limiting functional testing of developmental hypotheses. Efforts are being put into generating a transgenic line of the South American grey short-tailed opossum, Monodelphis domestica, by adapting the technique of spermatogonial stem cell (SSC) transplantation. This technique involves culturing and modifying SSCs in lab and transplanting them into a recipient male opossum. For the transplanted SSCs to colonize the recipient male testes, the recipient male must be evacuated of its own SSCs. Previous attempts to do so with the alkylating agent busulfan have proven unsuccessful. However, our recent attempts with x-ray irradiation have shown promising results. By applying two dosages of x-ray irradiation separated by a 2-week gap, we are able to selectively remove the germ cells while leaving the somatic cells intact. Based on histology and immunohistochemistry, irradiated specimens show no sign of spermatogonial recovery up to 166 days post-irradiation. The efficacy of x-ray irradiation at removal of endogenous SSCs allows us to move forward to the next phase in this project.

Thursday, June 3^rd, 2021 @ 5 PM