NUCLEIC ACID METABOLISM INVOLVED IN AUXIN-INDUCED ELONGATION OF YEAST CELLS

The following results were obtained using a variant yeast strain, N55, which can respond to the cell-elongating action of auxin. Base analogs of nucleic acids (2-thiouracil, 8-azaguanine, and 5-fluorouracil) inhibited the auxin-induced elongation of yeast cells only when they were added to the preculture prior to auxin treatment. The inhibitory effect of 2-thiouracil and 5-fluorouracil was reversed by uracil and that of 8-azaguanine by guanine. Actinomycin D inhibited the auxin-induced elongation when given to the culture containing auxin, but not when given to the preculture. The similarity in these respects between yeast and tissues of higher plants is discussed.