Precise Level of Cnbp is Required for Proper Rostral Head Development in Zebrafish - Abstract
Cellular nucleic-acid binding protein (Cnbp) is a highly conserved protein involved in both transcriptional and translational regulation of several genes. Knockout and knockdown studies suggest that Cnbp is required for proper craniofacial cartilages development. Here we provide a new insight into the influence of Cnbp dose on rostral head formation by overexpressing the wild-type Cnbp or a dominant negative mutant in both transient and stable transgenic approaches. The expression of neural crest marker genes and the development of craniofacial cartilages were adversely affected in either dominant negative or wild-type Cnbp transiently overexpressing specimens. The development of other embryonic structures was not affected neither by dominant negative or wildtype Cnbp overexpression, thus ruling out unspecific defects caused by the ectopic expression of Cnbp or its mutant. Results indicate that delimited level of Cnbp is required for proper rostral head development in zebrafish. Tol2-mediated transgenesis yielded up to 50% of stable wild-type Cnbp and 5% of dominant negative mutant overexpressing lines. Unlike observed in transient overexpression experiments, F2 offspring developed with no differences between controls and either of the two stable transgenics. Noteworthy, Cnbp levels in transiently overexpressing embryos were significantly higher than those ones measured in stable transgenics. Results suggest that stable transgenics derive from progenitors expressing constrained Cnbp levels.