DIFFERENTIATION OF MATING TUBES INDUCED BY THE MATING HORMONE RHODOTORUCINE A DURING THE MITOTIC CYCLE OF RHODOSPORIDIUM TORULOIDES

Abstract

The a-mating type cells of the basidiomycetous yeast Rhodosporidium toruloides were able to form mating tubes in response to the mating hormone, rhodotorucine A, given during 10min after the initiation of the bud emergence. The cells lost the susceptibility to the hormone after this period, and initiated DNA synthesis. It was indicated that commitment to mitosis occurred late in the G1 phase, prior to DNA replication, and that this commitment coincided with termination of the stage when the cells were morphologically susceptible to the hormone.