Inhibition of cell division and cell elongation in higher plants by inhibitors of DNA synthesis☆

[摘要] Lettuceseedlingswereincubatedinthepresenceandabsenceofgibberellin(GA3)insolutionscontainingdifferentinhibitorsofDNAsynthesis.GA3promotedtheelongationofthelettucehypocotylinthedark,andofbothhypocotylandcotyledonsinthelight;50%growthinhibitionwasobtainedby3×10−7M5-fluorodeoxyuridine(FUDR).InhibitionproducedbyFUDRat10−7to10−5Mwascompletelyreversedby10−4Mthymidine,butnotbyuridine.Theinhibitionproducedbyamethopterinwasonlypartlyreversedbythymidine;50%inhibitionwasobtainedat10−7Mofamethopterin,10−5MofmitomycinC,and2×10−3Mofphenethylalcohol.Intheinhibitedtissuesbothcelldivisionandcellelongationweresuppressed.Inepicotylsofdecapitatedlentilseedlings,whichgrowmainlybycellelongation,cellelongationwaspromotedbyGA3andwasinhibitedbyFUDRat10−7to10−5M.Thisinhibitionwasagainreversedbythymidine,butnotbyuridine.ThepossiblerelationshipbetweenDNAsynthesisandcellelongationinGA3-promotedtissuesisdiscussed.

[学科分类] 生物科学（综合）

[关键词] GA3;gibberellin A3;FUDR;5-fluorodeoxyuridine;MC;mitomycin C;PEA;phenethyl alcohol