Rat Lefty2/EBAF gene: isolation and expression analysis in the oviduct during the early pregnancy stage

It has been demonstrated, by RNA Arbitrarily Primed Polymerase Chain Reaction (RAP-PCR), that the endometrial bleeding associated factor (ebaf or lefty2) is expressed in rat oviduct. In this work we isolated and sequenced the full-length lefty2 cDNA from Rattus norvegicus oviducts and described its expression level in this organ during the estrous cycle and early pregnancy stage. The coding deduced sequence (CDS) codifies a 40.91 kDa protein with a highly conserved TGF-beta functional domain. RT-PCR semiquantitative analysis indicated that oviduct cells transcribe lefty2 among different stages of the estrous cycle with the maximum expression at diestrus phase. The highest expression of lefty2 was at the 4(th) day after mating (five folds respect to day one), just when the embryos have completed their transit through the oviduct. The lefty2 expression declined rapidly thereafter and the levels of their transcripts in the oviduct remained low until 7(th) days after mating.