Zebrafish cellular nucleic acid binding protein is envolved in the establishment of NCC craneofacial precursors.

WEINER, A; CALCATERRA, N.B.

Buenos Aires, Argentina

Simposio; 4th International Meeting of the Latin American Society of Developmental Biology.; 2008

Latin American Society of Developmental Biology

Cellular nucleic acid binding protein (CNBP) is a small single-stranded nucleic acid binding protein remarkably conserved among vertebrates. Cellular functions assigned to CNBP range from transcriptional regulation to translational control. Recently, it was reported that CNBP is required for forebrain formation during chick and mouse embryogenesis (Abe et al., 2007 & Chen et al., 2003). In this study, we have used the zebrafish model system to shed light on the basic understanding of CNBP molecular mechanisms and activity during vertebrate development. In order to knockdown CNBP expression during early development, both splicing as well as translation blocking morpholino oligonucleotides was designed. In order to obtain a similar effect and phenotype in both cases, the morpholinos should have been used at very different concentrations. Besides, different controls were performed to analyze their specificity and reliability. The CNBP depletion phenotype shows forebrain truncation and developmental retardation but the trunk appears normal. In situ hybridization assays showed that CNBP reduction did not affect CNS patterning while it caused diminution of neural crest derivatives, specially those ones involved in craniofacial structures development. Our data suggest an essential role for CNBP in mediating neural crest expansion by controlling proliferation and cell survival rather than via a cell fate switch during rostral head development. This possible role of CNBP may not only explain the craniofacial anomalies observed in zebrafish but also those reported for mice and chicken and, moreover, demonstrates that CNBP plays an essential and conserved role during vertebrate head development.