The establishment of the cartilage pattern in the embryonic chick wing, and evidence for a role of the dorsal and ventral ectoderm in normal wing development

[摘要] Previousinvestigationshaveindicatedthatthelimbbudbehavesasamosaicaftersomeexperimentalmanipulationsandregulatesafterothers.Inlightofnewmapsoftheprospectivecartilage-formingregionsofthechickwing,wehavereinvestigatedthestabilityofthelimbpatternbytwoexperimentalprocedures.First,theprospectivelongboneregionswereexcisedtoexaminetheabilityofthecellsoutsideoftheprospectivelongboneregionstoformnormallongbones.Second,themesoderm,mesoderm+dorsalandventralectoderm,ordorsalectoderm(withasmallamountofsubjacentmesoderm)oftheprospectiveelbowregionwererotated180°toexaminetheabilityofthelimbtocontrolandregulatethedifferentiationofthecellsinthelimb.Wecanconcludefromtheseexperimentsthatthecartilage-formingregionsofthelimbmesodermgraduallybecomestabilizedbetweenstage22andstage24,andthatthestabilizationisduetotheadvancedstateofdifferentiationandtothedecreasedrateofcelldivisionafterstage22.Inaddition,thedorsalandventralectodermhavebeenshowntoaidinstabilizationofthecartilagepatternandtoinfluencethedevelopmentofthehumerus.Weconcludethatthedorsalandventralectodermplayasignificantroleinlimbdevelopment.

[学科分类] 生物科学（综合）