Control of microtubule pattern during the development of a large organelle in the ciliate Nassula
[摘要] BundlesofhexagonallyarrangedmicrotubulesinthecytopharynxofNassuladevelopabnormallyduringcolchicinetreatment.Someofthetubulesundergoamicrotubule-macrotubuletransition.Portionsoftubulesthatassembleduringthetreatmentfailtogrowalongstraightpathsandareirregularlyarranged.Portionsofthesametubuleswhichassembleaftertreatmentarearrangedhexagonally.Comparisonsofnormaldevelopmentwiththatoccurringduringandaftercolchicinetreatmentindicatethatseveralproceduresareinvolvedindefiningmicrotubulearrangement.Itseemsthathighlyorderedarraysofmicrotubulenucleatingsitesformagainsttheproximalendsofbasalbodies.Eacharrayofsitesapparentlydeterminesthecross-sectionalshapeofabundleandtheorientationofthehexagonallatticepatterninwhichitstubulesarearrangedbyspecifyingthepositionsinwhichtubulesstarttoassemblefairlyexactly.Thetermmicrotubule-nucleating-templateisproposedforarraysofsitesthatactinthisway.Aspecialclose-packing-effectmaymaintainthehexagonalpatternastubuleslengthenuntiltubulesareconnectedbylinks.Linksmainlyattachtoparticularbindingpointsontubulewalls.Sincelinkscanprojectinavarietyofdirectionsfromthesepoints,linksprobablydonotplayanimportantroleinestablishingtubulearrangementinthisorganelle.
[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]
