Molecular Cloning and Characterization of Juvenile Hormone Acid Methyltransferase in the Honey Bee, Apis mellifera, and Its Differential Expression during Caste Differentiation
AmJHAMT gene cloned from honey bee larvae encodes a juvenile hormone acid methyltransferase that catalyzes the final methylation of JH biosynthesis. Phylogenetic analysis shows that AmJHAMT is clustered with all other Hymenopteran JHAMT orthologs to form an independent major clade. Significant differences between the temporal AmJHAMT mRNA and protein expression profiles in queen and worker larvae suggest that proper developmental regulation of this gene is crucial for female caste differentiation in Apis mellifera. Additionally, remarkable down-regulation of AmJHAMT from the end of L5 to Pw in both queens and workers indicates that suppression of this gene might play an important role in the metamorphosis of honey bees. More studies are needed to further explore these functions of AmJHAMT in honey bee physiology.