Expression of TAM family members and their ligand in WT and Axl/Tyro3 null ovaries. Panel A: mRNA levels were measured by semi quantitative RT-PCR amplification of Axl, Tyro3, Mer, and Gas6 transcripts isolated from total ovarian RNA. Panel B: Protein levels displayed by immunoblot of ovarian lysates. Both AXL and TYRO3 exhibit doublet bands at approximately 120 and 140 KDa(Bellosta, Costa, Lin et al., 1995,Costa, Bellosta and Basilico, 1996) (note faint larger bands from nonspecific binding of Tyro3 antibody)(Lai and Lemke, 1991). GAPDH was used as an internal control.