Appearance and distribution of fibronectin during chick embryo gastrulation and neurulation☆
[摘要] Thedistributionoffibronectin(FN)wasstudiedbyimmunofluorescenceduringgastrulationandearlyneurulationinavianembryos.FNwasfirstdetectedundertheupperlayer(ul),justpriortothestreakappearance.Duringgastrulation,FNwasrestrictedtothebasementmembraneoftheul.ThestreakinitiallyappearedasaprotrudingcellmasslimitedbyFNstrands.Lateron,FNdisappearedlocallywherethestreaksankintothespaceundertheul.Inthestreak,theinvaginatedcellsseparatedandmigratedlaterallyalongtheFN-richbasementmembraneoftheul.FNappearedinthebasalsurfaceofthedefinitiveendoderm,whenitwascompleted.Ourresultssuggestthat,priortogastrulation,passivecellmovementsoccurintheabsenceofFN,whileduringgastrulation,FNisinvolvedinactivemovements.Inthehead,earlyneurulationfollowedtheseparationofthenotochordfromtheneuralplatebyaFN-richbasementmembrane.Incontrast,inthetrunk,theneuralgrooveappearedfirstandremainedincloseappositionwiththenotochordandsomiticmesenchymetwiceaslongasinthehead.AnintenseFNstainingwasrevealedfirstbetweentheneuraltubeandthesomite,andlateronbetweentheneuraltubeandthenotochord.
[发布日期] [发布机构]
[效力级别] [学科分类] 生物科学（综合）
[关键词] [时效性]
