Figure 3: Cardiovascular transcription factor expression in isolated neonatal sheep cell clones. Neonatal sheep cardiovascular cell clones shown were tested by PCR for expression of Isl 1 and GATA-4. All seven clones expressed transcripts for Isl1 (A, Isl1 size=131bp) and a proportion of these clones expressed transcripts for GATA-4 (B, GATA-4 size=188bp).