Radar Is Required for the Establishment of Vascular Integrity in the Zebrafish

[摘要] Thepreciseassemblyofanintegratednetworkofbloodvesselsisessentialforthesurvivalofvertebrateembryos.However,theprocessesbywhichprimitiveendothelialcellsformmaturevesselscapableofsupplyingoxygenandnutrientstodevelopingtissuesremainincompletelyunderstood.Here,weproposearoleforRadar,oneofthezebrafishorthologuesofgdf6,inestablishingintegrityofthetrunkvasculatureinzebrafishembryos.Weshowthatradarexpressionisappropriatelyplaced,bothspatiallyandtemporally,toperformsucharole.Transcriptsforradararedetectedinthehypochordandtheprimitivegutendoderm.Thesetissuesintimatelyflankdevelopingaxialvesselsinthetrunkandhavebeenpreviouslyimplicatedintheregulationofvasculardevelopment.Morpholino-basedtargetedgeneknock-downhasgeneratedaRadar-specificloss-of-functionzebrafishmodel.Theseembryosdisplaynormalinitiationofvascularpatterningandcommencementofcirculation.However,byday2ofdevelopment,theintegrityoftheaxialvasculatureiscompromisedwithhemorrhagesandcirculationshort-circuitsthroughoutthedevelopingtrunk.Weshowthatthisaberrantvasculardevelopmentisspecifictoareductionoftheradargeneproduct.TheseresultssuggestthatRadarisinvolvedinasignalingpathwayrequiredforestablishingtheintegrityoftheaxialvesselsduringzebrafishdevelopment.

[学科分类] 生物科学（综合）

[关键词] radar;GDF6a;BMP;TGF-β;zebrafish;angiogenesis;hypochord;vasculogenesis;morpholino;microangiography