Figure 4: RT-PCR analysis of Figf mRNA splice variant expression in implantation site tissue segments from the uteri of Day 5.5-10.5 of pregnancy. Abbreviations: b.p., base pair; Figf326 (primer set 1) and Figf358 (primer set 2) amplicons are from the two mRNA splice variants which encode 326 and 358 amino acid FIGF proteins.