Analisis of CNBP expression pattern in zebrafish embryo and characterisation of some binding targets.

WEINER, A.; BOLOGNA, N.; ARMAS, P.; CACHERO, S.; CALCATERRA, N. B.

Iguazú, Misiones, Argentina.

Congreso; XL Anual Meeting of the Argentine Society for Biochemestry and Molecular Biology.; 2004

Argentine Society for Biochemestry and Molecular Biology.

Cellular nucleic acid binding protein (CNBP) is a strikingly conserved single-stranded nucleic acid binding protein containing seven CCHC zinc knuckle domains. CNBP function is not clearly understood yet, however it has been associated with diverse gene expression control mechanisms involving from transcription to translation and related to cell proliferation events. Considering that early development shows a high cell division rate and making use of the advantages of zebrafish as animal model, we carried out whole-mount in situ hybridization and immunohistochemistry assays to analyze the zCNBP-mRNA and protein expression pattern in early embryos. Both of them,  mRNA and protein, are evenly distributed in zebrafish embryo. However, we observed that CNBP translocates to the nucleus once the zygotic transcription starts, suggesting a role in transcription regulation or in newly synthesised RNA folding assistance. Electrophoretic mobility shift assays were performed to analyze the capability of recombinant zCNBP to bind to single-stranded nucleic acid probes which have different sequences and secondary structures. zCNBP binds specifically to several oligonucleotides with sequences corresponding to 5’UTR from certain maternal mRNAs that are translationally regulated during early development.