Fig. 4.
RT-PCR analysis of ES-cell/OP9 cocultures.
Expression of transcripts for CD105, TbR-II, ALK1, and β-actin was analyzed by RT-PCR. The cDNAs for analysis were prepared directly from OP9 cells, E15 FL cells, and ES-cell/OP9 cocultures at days 5, 8, and 12 (total unfractionated cells were passaged and reseeded at day 5). Control RT-PCRs were performed in the absence of cDNA templates (dH2O) and with the use of β-actin primers.