Conditional restoration and inactivation of Rbm47 reveal its tissue-context requirement for viability and growth

Rbm47 encodes a RNA binding protein that is necessary for Cytidine to Uridine RNA editing. Rbm47^gt/gt mutant mice that harbor inactivated Rbm47 display poor viability. Here it was determined that the loss of Rbm47^gt/gt offspring is due to embryonic lethality at mid-gestation. It was further showed that growth of the surviving Rbm47^gt/gt mutants is impaired. Rbm47 is expressed in both the visceral endoderm and the definitive endoderm. Using the utility of the switchable FlEx gene-trap cassette and the activity of Cre and FLP recombinases to generate mice that conditionally inactivate and restore Rbm47 function in tissue-specific manner, it was demonstrated that Rbm47 function is required in the embryo proper, and not the visceral endoderm, for viability and growth.