Functional Characterization of a Fatty Acyl Reductase Identified from the Female Pheromone Gland of Mythimna loreyi (Lepidoptera: Noctuidae)

Sex pheromones, which play a critical role in mediating sexual communication of Lepidoptera, are biosynthesized by a variety of particular enzymes in specialized pheromone glands (PGs). Among these enzymes, fatty acyl-CoA reductases (FARs) catalyze the reduction of fatty acyl precursors to their corresponding alcohols. In this study, we identified 32 FARs from the genome of Mythimna loreyi, an important agricultural pest. Among all MlorFARs identified, only MlorFAR1 showed a PG expression pattern and exhibited a positive response to pheromone biosynthesis activating neuropeptide (PBAN) injection. Silencing MlorFAR1 reduced pheromone titers by 70.4-88.9% and significantly reduced mating rates at the 48-72 h postinjection time point. Heterologous expression in yeast confirmed that MlorFAR1 preferentially converted medium-chain fatty acid methyl esters to alcohols. These findings establish MlorFAR1 as a pivotal enzyme in the biosynthesis of sex pheromones in M. loreyi, providing a framework for the development of innovative pest management strategies.