The zebrafish cerebellar rhombic lip is spatially patterned in producing granule cell populations of different functional compartments

摘要

Theupperrhombiclip,aprominentgerminalzoneofthecerebellum,wasrecentlydemonstratedtogeneratedifferentneuronalcelltypesovertimefromspatialsubdomains.WehavecharacterizedthedifferentiationoftheupperrhombiclipderivedgranulecellpopulationinstableGFP-transgeniczebrafishinthecontextofzebrafishcerebellarmorphogenesis.Time-lapseanalysisfollowedbyindividualgranulecelltracingdemonstratesthatthezebrafishupperrhombiclipisspatiallypatternedalongitsmediolateralaxisproducingdifferentgranulecellpopulationssimultaneously.Time-lapserecordingsofparallelfiberprojectionsandretrogradelabelingrevealthatspatialpatterningwithintherhombiclipcorrespondstogranulecellsoftwodifferentfunctionalcompartmentsofthematurecerebellum:theeminentiagranularisandthecorpuscerebelli.Thesecerebellarcompartmentsinteleostscorrespondtothemammalianvestibulocerebellarandnon-vestibulocerebellarsystemservingbalanceandlocomotioncontrol,respectively.Giventhehighconservationofcerebellardevelopmentinvertebrates,spatialpartitioningofthemammaliangranulecellpopulationandtheircorrespondingearlier-produceddeepnucleibypatterningwithintherhombiclipmayalsodelineatedistinctfunctionalcompartmentsofthecerebellum.Thus,ourfindingsofferanexplanationforhowspecificfunctionalcerebellarcircuitriesarelaiddownbyspatio-temporalpatterningofcerebellargerminalzonesduringearlybraindevelopment./p/div