Experimental modulation of intercellular cohesiveness: Reversal of tissue assembly patterns☆
[摘要] Aftercellsortingorthefusionoftissuefragments,chickembryoniclivercellpopulationstypicallytendtosurroundheartcellpopulations.Weshowherethatbyvaryingtheratioofhearttolivercellsinmixedreaggregates—ortherelativesizesofheartandliverreaggregatesinreaggregate-fusions—theinsidevsoutsidepositionsadoptedbythesetwocellpopulationscanbereversed.Bycontrast,undissociatedliverfragmentstendtoenvelopheartfragments,irrespectiveoftheirrelativesizes.Ourexperimentshererevealtwosourcesofposition-reversalbehavior.(1)Trypticdissociation-reaggregationcauseshearttissuetobecomemoreexternalizing;and(2)invitrocultureconditionscausehearttissuetobecomemoreinternalizing.Previousevidenceindicatesthatlesscohesivecellpopulationstendtoenvelopmorecohesiveones.Itappearsthat,regardlessoftheheart:liverratio,reaggregatedheartcellsareinitiallylesscohesivethanreaggregatedlivercells,butduringsubsequentculturingbecomethemorecohesivepopulation.Thistissue-specificchangeinrelativecohesivenessresultsinposition-reversalbehavior,thedetectionofwhichis,forstrictlymechanicalreasons,facilitatedbyvariationsinphaseratio.Acriticaltestreportedhereconfirmsthisinterpretation.Positionreversalbehaviorillustrateshowachangeinintercellularcohesivenessinthecourseofnormaldifferentiationcouldinitiateamorphogenetictissuemovement.
[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]
