Differential gene expression and developmental competence in in vitro produced bovine embryos

Autor(es)

Ripamonte, Paula ^[1] ; Mesquita, Ligia Garcia ^[1] ; Cortezzi, Sylvia Sanches ^[1] ; de Carvalho Balieiro, Julio Cesar ^[1] ; Fonseca Merighe, Giovana Krempel ^[1] ; Watanabe, Yeda Fumie ^[1] ; Caetano, Alexandre Rodrigues ^[2] ; Meirelles, Flavio Vieira ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, FZEA, Dept Ciencias Basicas, Pirassununga, SP - Brazil

^[2] EMBRAPA Recursos Genet & Biotecnol, Brasilia, DF - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ZYGOTE; v. 20, n. 3, p. 281-290, AUG 2012.
• Citações Web of Science: 5

Resumo

The embryonic developmental block occurs at the 8-cell stage in cattle and is characterized by a lengthening of the cell cycle and an increased number of embryos that stop development. The maternal-embryonic transition arises at the same stage resulting in the transcription of many genes. Gene expression studies during this stage may contribute to the understanding of the physiological mechanisms involved in the maternal-embryonic transition. Herein we identified genes differentially expressed between embryos with high or low developmental competence to reach the blastocyst stage using differential display PCR. Embryos were analysed according to developmental kinetics: fast cleavage embryos showing 8 cells at 48 h post insemination (hpi) with high potential of development (F8), and embryos with slow cleavage presenting 4 cells at 48 hpi (54) and 8 cells at 90 hpi (S8), both with reduced rates of development to blastocyst. The fluorescence DDPCR method was applied and allowed the recovery of 176 differentially expressed bands with similar proportion between high and low development potential groups (52% to F8 and 48% in S4 and S8 groups). A total of 27 isolated fragments were cloned and sequenced, confirming the expected primer sequences and allowing the identification of 27 gene transcripts. PI3KCA and ITM2B were chosen for relative quantification of mRNA using real-time PCR and showed a kinetic and a time-related pattern of expression respectively. The observed results suggest the existence of two different embryonic genome activation mechanisms: fast-developing embryos activate genes related to embryonic development, and slow-developing embryos activate genes related to cellular survival and/or death. (AU)

• Processo FAPESP: 99/12351-3 - Transcrição e bloqueio embrionário em bovinos
• Beneficiário: Flávio Vieira Meirelles
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 02/02532-5 - Genômica funcional da ativação do genoma e do bloqueio embrionário em bovinos
• Beneficiário: Paula Ripamonte Figueiredo
• Modalidade de apoio: Bolsas no Brasil - Doutorado