Morpholino knockdown of the zebrafish CENTA2 orthologue results in cardiovascular defects

Cardiovascular malformations (CVMs) have a higher incidence in patients with NF1 microdeletion syndrome, compared to classical NF1 patients (18% vs 2%), presumably owing to haploinsufficiency of genes lying in the deletion interval and important for cardiac morphogenesis. One of the possible candidate genes for CVMs onset inside the deletion, CENTA2, was found, by WISH (Whole-mount In Situ Hybridization) on mouse embryos, to be turned on in heart at 9-9.5 dpc, when the heart tube is looping and the valves and septa are forming, suggesting a role in heart development. In order to provide further evidence on a possible role of CENTA2 in cardiac development, we employed zebrafish as a model system. Zebrafish is a useful model that allows a detailed cardio-vascular analysis even in embryos with severe defects that would be lethal in other organisms. We performed loss-of-function experiments injecting a morpholino that is able to block the mRNA translation of the zebrafish CENTA2 orthologue, centa2-like. At 2 dpf the injected embryos displayed in vivo circulatory and cardiac defects, such as blood stases in the head and caudal region, block of circulation and heart shape defects. A preliminary molecular characterization on morphants at 2 dpf showed that the injection of the centa2-like morpholino caused heart looping defects, in particular the formation of a tubular heart or an inverted heart looping. WISH analysis on morpholino-injected embryos at different developmental stages with different cardiac markers will allow further investigation of the role of centa2-like during zebrafish cardiac morphogenesis