In vivo analysis reveals a critical role for neuropilin-1 in cranial neural crest cell migration in chick

摘要

Theneuralcrestprovidesanexcellentmodelsystemtostudyinvasivecellmigration,howeveritisstillunclearhowmolecularmechanismsdirectcellstoprecisetargetsinaprogrammedmanner.Weinvestigatetheroleofapotentialguidancefactor,neuropilin-1,andusefunctionalknockdownassays,tissuetransplantationandinvivoconfocaltime-lapseimagingtoanalyzechangesinchickcranialneuralcrestcellmigratorypatterns.Whenneuropilin-1functionisknockeddowninovo,neuralcrestcellsfailtofullyinvadethebranchialarches,especiallythe2ndbranchialarch.Time-lapseimagingshowsthatneuropilin-1siRNAtransfectedneuralcrestcellsstopandcollapsefilopodiaatthe2ndbranchialarchentrances,butdonotdie.Thisphenotypeiscellautonomous.Totesttheinfluenceofpopulationpressureandlocalenvironmentalcuesindrivingneuralcrestcellstothebranchialarches,weisochronicallytransplantedsmallsubpopulationsofDiI-labeledneuralcrestcellsintohostembryosablatedofneighboring,premigratoryneuralcrestcells.Time-lapseconfocalanalysisrevealsthatthetransplantedcellsmigrateinnarrow,directedstreams.Interestingly,withthereductionofneuropilin-1function,neuralcrestcellsstillformsegmentalmigratorystreams,suggestingthatinitialneuralcrestcellmigrationandinvasionofthebranchialarchesareseparableprocesses./p/div