The cholesterol-hydroxyecdysone-vitellogenin pathway is involved in the longevity of trophocytes and oenocytes of queen honey bees (Apis mellifera)

Trophocytes and oenocytes in the abdomen of honey bees do not divide after eclosion; however, trophocytes and oenocytes of queen bees have a longer lifespan and maintain better cellular function than those of worker bees. To explore this phenomenon, we assayed the molecules involved in the cholesterol-hydroxyecdysone-vitellogenin (Vg) pathway in the trophocytes and oenocytes of young and old worker and queen bees. The results showed that Vg and cholesterol levels in hemolymph and cholesterol levels, 20-hydroxyecdysone (20E) levels, and the messenger RNA levels of cytochrome P450 314A1 20-hydroxylase (Cyp314A1), ecdysone receptor isoform A (EcR-A), ecdysone receptor isoform B1 (EcR-B1), ultraspiracle (USP), ecdysone-induced protein 74 (E74), ecdysone-induced protein 75 (E75), broad-complex (BR-C), Vg, and Vg receptor (VgR) in trophocytes and oenocytes were increased in queen bees compared with worker bees. These findings indicated that queen bees have higher expression of molecules in the cholesterol-hydroxyecdysone-Vg pathway than worker bees.