STUDYING RETINA DEVELOPMENT USING SMALL MOLECULE BMP INHIBITORS AND MAKING STABLE MOUSE EMBRYONIC STEM CELL LINES

Abstract

Age related macular degeneration results in loss ofconephotoreceptors. Studies have not been able to efficientlytransplant cone cells, possiblydue to their limited numbersand lack of information about their development in the mammalian retina.Our lab has discoveredthat BMP signal inhibition is important for eye developmentin the frogas well as generating retinal cone photoreceptorsin mouse embryonic stem cell cultures. The frog, Xenopus laevis,can grow eyeswithin a few days; it is also amenable to transplantation and genetic alteration. In this study, two small molecule BMP inhibitors, LDN193189 and Dorsomorphin, causedshortened tails(dorsalized) phenotypein Xenopusembryos as well asexpansionofthe neural plate in neural stage embryos. This suggests that these chemical inhibitors can be used in place of the standard BMP antagonist, Noggin, in cell culture experiments. Mouse embryonic stem cell cultures treated with Noggin have been used to generate retinal progenitors that generate cone photoreceptorsin our lab. In order to further study cones indetail,we needed to enrich the population of cone photoreceptors from retinal progenitors by marking these cells in-­‐vitro. We generated stable mouse embryonic stem cells expressing a promoter that drives expression in rod/cone progenitor cells upstream from the mCherry fluorescent protein. This construct also contained aubiquitous promoterdriving an antibiotic resistance genefor antibiotic selection. In future studies, these stable ES celllines could be used to differentiate into rod/cone progenitors selected specifically by FAC sorting. Small molecule BMP inhibitors could be used in place of Noggin and analyzed in the generation of conecells.