A gene for carotene cleavage required for pheromone biosynthesis and carotene regulation in the fungus Phycomyces blakesleeanus

► The order Mucorales use apocarotenoids derived from β-carotene as sexual pheromones. ► carS mutants of Phycomyces do not cleave β-carotene or produce apocarotenoids. ► The Phycomyces carS gene was identified by map-based cloning. ► carS encodes a β-carotene oxygenase as the first step in pheromone biosynthesis.