Chromatin proteins from normal, vegetalized, and animalized sea urchin embryos

[摘要] Thechemicalcompositionofthechromatin,thefractionalcontentofhistonesandnonhistonechromatinproteins(NHP),andthebiosynthesisoftheseproteinsinnormal,vegetalized,andanimalizedembryosoftheseaurchinStrongylocentrotusdroebachiensisattheblastula,mesenchymeblastula,andgastrulastageshavebeenstudied.TheamountoftheNHPinthechromatinfromnormalandvegetalizedembryosincreasesduringearlyembryonicdevelopmentwhilethatinanimalizedembryosremainswithoutchangeatthemesenchymeblastulastageandthendecreases.Duringdevelopmentthehistonecontentinallthreecasesslightlydecreases.Polyacrylamidegelelectrophoresisrevealsthatbothfractionalcompositionofhistonesandtheirbiosynthesisinnormal,vegetalized,andanimalizedembryosdisplaynodifferences.Duringdevelopment,however,somechangesoccur,sothattherelativeamountofhistonesF1andF2a2increases,F2bdecreases,whileF3andF2a1remainsconstant.HistoneF1attheblastulastageconsistsoftwosubfractionswhileatthegastrulastageitconsistsofthreesubfractions.ThehistoneF2a1consistsofoneandtwo,respectively.HistoneF3atallstagesismadeupofthreesubfractions;histoneF2bismadeupoftwo;andthehistoneF2a2iselectrophoreticallyhomogeneous.Specificradioactivityofthearginine-richhistonesF3andF2a1tendstoincreaseduringdevelopment,whilethatofmoderatelylysine-richhistonesF2bandF2a2doesnotchange,andthatofthelysine-richhistoneF1decreases.TheNHPinnormal,vegetalized,andanimalizedembryosatdifferentdevelopmentalstagesconsistof17fractionsthatcanbeseparatedbyisoelectrofocusingwithinthe4.5–8.8pHrange.QuantitativechangeshavebeenobservedinthefractionsfocusedatpH4.5–6.1duringdevelopmentandinnormalandmodifiedembryosatthegastrulastage.

[学科分类] 生物科学（综合）