Parasitism by the ectoparasitioid, Habrobracon hebetor alters the development and expression patterns of genes related to hormone synthesis and regulation process in its hosts.

Kaili Yu; Juefeng Zhang; Jin Chen; Fang Li; Xue Bai; Shijiao Xiong; Xinhai Ye; Haiying Zhong; Fang Wang; Hongwei Yao; Qi Fang; Hongxing Xu; Qisheng Song; Gongyin Ye

The growth and development of Ploidia interpunctella larvae into pupae was hindered by the parasitism of Habrobracon hebetor. However, the underlying mechanisms by which the ectoparasitoid H. hebetor altered its development remain elusive. In the present study, we measured the titers of growth and development-related juvenile hormone (JH) and 20-hydroxyecdysone (20E) and evaluated the expression levels of relevant genes in parasitized and non-parasitized hosts. The results showed that JH I and JH III were substantially more prevalent in the parasitized larvae than in the non-parasitized ones 12 h post parasitism, while there was no significant difference in JH II titer between the two. On the contrary, 20E titer was significantly lower in the parasitized larvae, compared to a considerable peak in the non-parasitized larvae 36 h post parasitism. Parasitism promoted the transcription of JH synthesis-related genes Jhamt and Dpp at 6-9 h, proceeding the rising JH titer at 12 h. While the transcription of 20E synthesis-related genes Nvd, Sro, Spo, Dib and Shd, and 20E receptor genes EcR1, EcR2 and USP were suppressed, there were no discernible effects on the transcription of PTTH whose protein product is responsible for stimulating 20E synthesis. Overall, the parasitism by H. hebetor increased JH titer via promoting JH synthesis related gene expression and decreased 20E titer by inhibiting 20E synthesis related genes in P. interpunctella larvae it parasitized, thus suspending host larval growth to allow parasitoid larval development.

GENE expression; JUVENILE hormones; HORMONE synthesis; GENETIC transcription; HORMONE regulation

Entomologia Generalis, 2024, Vol 44, Issue 6, p1525

0171-8177

Academic Journal

10.1127/entomologia/2024/2747