Juvenilization of Haller's organ regenerates in ixodid ticks (Acarina, Ixodidae) under an influence of insect juvenile hormone mimics.

摘要

The adult regenerates of Haller's sensory organ in the prostriate tick Ixodes ricinus reestablish the atavistic features (through a multiplication of some sensilla), while the nymphal regenerates, in contrast, reestablish the larval features of theorgan (through a reduction of some sensilla). Juvenoids (methoprene and insegar [fenoxycarb]) exert a juvenilization of its adult regenerates (in terms of suppression and restraint of sensillar multiplication) with acquiring features similar to nymphal regenerates or to naive larval organs. The juvenilizing effect of methoprene is characteristic for both prostriate and metastriate ticks, inasmuch as similar changes (although less pronounced) are revealed also by Haller's organ regenerates in adult Hyalomma anatolicum ticks. The obtained data confirm the hypothesis (Belozerov, Kok a. Fourie, 1997) suggesting that the character of structural changes in Haller's organ during both normal metamorphosis and reparative regeneration is dependent on juvenile hormone content during regenerative processes at successive life-cycle stages. This gives the first experimental evidence of the role of insect juvenile hormone mimics in hormonal control of developmental processes (morphogenesis, differentiation) in Acari.