The zygomycete Blakeslea trispora is used commercially to produce beta-carotene. Trisporic acid (TA), the previously discovered pheromone of B. trispora, is considered to be the main inducer of carotene biosynthesis. To gain insight into the regulatory mechanisms of TA that controls terpenoid biosynthesis, changes in the contents of beta-carotene, ubiquinone, and ergosterol in the (-) strain of B. trispora after TA addition were measured. Transcription products of eight genes encoding enzymes in terpenoid biosynthesis were also analyzed. The addition of TA to the B. trispora culture increased the production of beta-carotene and ubiquinone, while the ergosterol content remained unchanged during the first 48 h after TA addition and decreased slightly thereafter. Four genes in the beta-carotene biosynthetic pathway (ipi, carG, carRA, and carB) had increased expression following TA addition. These data suggest that TA increases terpenoid production in B. trispora by stimulation of transcription. This study contributes to a better understanding of the regulatory mechanisms of TA on terpenoid biosynthesis. (C) 2012 Elsevier Ltd. All rights reserved.