Stable Anterior Anchoring of the Oocyte Nucleus Is Required to Establish Dorsoventral Polarity of the Drosophila Egg

[摘要] InDrosophila,dorsoventralpolarityisestablishedbytheasymmetricpositioningoftheoocytenucleus.Ineggchambersmutantforcap‘n’collar,theoocytenucleusmigratescorrectlyfromaposteriortoananterior–dorsalpositionwhereitremainsduringstage9ofoogenesis.However,attheendofstage9,thenucleusleavesitsanteriorpositionandmigratestowardstheposteriorpole.ThemislocalisationofthenucleusisaccompaniedbychangesinthemicrotubulenetworkandafailuretomaintainbicoidandoskarmRNAsattheanteriorandposteriorpoles,respectively.gurkenmRNAassociateswiththeoocytenucleusincap‘n’collarmutantsandinitiallythelocalsecretionofGurkenproteinactivatestheDrosophilaEGFreceptorintheoverlyingdorsalfolliclecells.However,despitethepresenceofspatiallycorrectGrksignallingduringstage9,eggslaidbycap‘n’collarfemaleslackdorsoventralpolarity.cap‘n’collarmutants,therefore,allowforthestudyoftheinfluenceofGrksignaldurationonDVpatterninginthefollicularepithelium.

[学科分类] 生物科学（综合）

[关键词] oocyte polarity;axis formation;nuclear migration;microtubule network;RNA localisation;gurken;DER;pipe