Filia is a maternal effect gene important for female reproduction. In the present study, bovine Filia expression was studied at mRNA and protein level. Oocytes were matured and fertilized and embryos were cultured to blastocyst stage. RNA were extracted from bovine ovary, oviduct, lung, heart, liver, 30- to 40-day fetus, immature oocytes, matured oocytes, 2-,4-, 8- to 16-cell embryos and blastocysts. Primers were designed to amplify 164 bp and 443 bp fragments. Bioinformatic analysis and a 3?RACE-PCR experiment were performed to analyze the whole Filia mRNA. A Real-Time PCR was performed to compare the mRNA level in different stages of in vitro development, with immature oocytes. Immunofluorescence analysis was performed on bovine ovary, oviduct and uterus. RT-PCR results showed that Filia transcripts are only detected in ovary, oocytes and different stages of embryo development. By 3?RACE-PCR only a 1600 bp fragment was amplified. Bioinformatic analysis indicated one transcription start site and three exons for Filia gene. Filia expression significantly increased at 8- to 16-cell stage which shows embryonic activation of Filia gene, and it decreased at blastocyst. Immunofluorescence showed Filia protein expression in bovine oocyte cytoplasm. We suggest an important role for Filia in bovine reproduction. Keywords: Bovine Filia gene, Oocyte, Blastocyst, RACE-PCR, Embryonic activation, Immunofluorescence.
