Microtubule proteins in axolotl eggs and developing embryos☆

[摘要] TubulinfromeggsandembryosoftheMexicanaxolotlwascharacterizedbyelectrophoresisandcolchicinebinding.Inurea-polyacrylamidegelelectrophoresis,solubleaxolotleggtubulinmigratedastwobands,identicaltotubulinsfromseaurchinspermandDrosophilaeggs.However,inSDS-containinggels,onwhichtheαandβsubunitsofstandardtubulinswerewellresolved,axolotleggtubulinmigratedasasinglebandwithanapparentmolecularweightof53,500.Themethodofdisruptionoftheeggsaffectedbothyieldoftubulinfromvinblastinesulfateprecipitatesandstabilityofthecolchicinebindingactivity.Thecolchicinebindingactivityofsolubletubulinfromgentlydisruptedeggswasspecificandofhighaffinity,withpropertiessimilartothosereportedforothertubulins.Thetubulinpoolinunfertilizedeggswasdeterminedtobeapproximately2μg/egg;theleveldecreased20%afterinitiationofcleavageandthenremainedconstantthroughdevelopmenttopostneurulastages.Thecolchicinebindingactivityofsolubletubulinfromembryoswasmuchlessstablethanthatofunfertilizedeggsanddecreasedfurtherduringdevelopment.Nodifferenceswerefoundinpropertiesoftubulinfromeggsofseveralstrainsofnormallypigmentedaxolotls;however,tubulinfromalbinoeggsshowedslightlydifferentpropertiesinbothelectrophoresisandcolchicinebinding.Thecolchicinebindingactivityofsolubletubulinaccountsforonlyhalfthetotalactivityinaxolotleggs;theypossess,inaddition,aparticulatenontubulincolchicinebindingactivity.

[学科分类] 生物科学（综合）