Pattern of unequal cell division and development in Caulobacter crescentus☆

[摘要] ThepatternofasymmetricdivisionhasbeenexaminedinCaulobactercrescentus(gram-negativeaquaticbacteria)bydeterminingthepositionofthe“divisionsite”oncellsofdifferentages.Measurementsofcellwidthandlengthatthissite,whichcorrespondstothepointofeventualcellseparation,weremadeonelectronmicrographsofcellsstainedwithphosphotungsticacid.Theresultsshowthat(i)thedivisionsiteisformedearlyinthecellcycleanditconstitutesthefirstvisiblefeatureonthegrowingstalkedcelltodifferentiatetheincipientswarmercell,(ii)thedivisionsiteislocatedasymmetrically(closertotheswarmerpolethanthestalkedpole)onthedividingcell,(iii)itspositionrelativetothestalkedandswarmerpolesdoesnotchangeduringthecellcycle,and(iv)divisionisconsequentlyunequal,withtheswarmercellalwayssmallerthanthestalkedcell.Theimplicationsofthesefindingsforgeneralmodelsofunequalcelldivisionandstemcelldevelopmentarediscussed.

[学科分类] 生物科学（综合）