Molecular mechanisms of juvenile hormone signaling in insect development

Mgr. Matěj MILÁČEK

Disertační práce

Identification of genes immediately downstream of JHR using DamID

Abstract:

This thesis comprises four chapters focused on molecular mechanism of juvenile hormone (JH) in insect development. JH receptor (JHR) signaling represents an attractive target for development of selective tools for pest control, as JH is vital to insects but absent from vertebrates. The first chapter provides evidence for the conserved function of the JHR in evolutionarily basal hemimetabolous insects. The second chapter uncovers the molecular mode of action of compounds that selectively target a particular insect taxon without affecting related species, indicating the possibility of species-selective JHR agonists. The third chapter introduces JHR agonists identified through high-throughput screening that selectively activate the JHR of target insects. We show that these compounds disrupt insect development through induction of the JH-response gene Kr-h1 in a species-selective manner. The fourth chapter focuses on identification of direct JHR target genes during development of Drosophila melanogaster. In this model organism, we implemented a novel technique, targeted DamID, to profile genome-wide protein-DNA interactions of the JHR in a selected tissue. We reveal a previously unrecognized role of JH in Drosophila larval development and identify a gene mediating this role. Together, these findings contribute to better understanding of JH signaling and support development of safer, species-selective pest control tools.

Abstract:

This thesis comprises four chapters focused on molecular mechanism of juvenile hormone (JH) in insect development. JH receptor (JHR) signaling represents an attractive target for development of selective tools for pest control, as JH is vital to insects but absent from vertebrates. The first chapter provides evidence for the conserved function of the JHR in evolutionarily basal hemimetabolous insects. The second chapter uncovers the molecular mode of action of compounds that selectively target a particular insect taxon without affecting related species, indicating the possibility of species-selective JHR agonists. The third chapter introduces JHR agonists identified through high-throughput screening that selectively activate the JHR of target insects. We show that these compounds disrupt insect development through induction of the JH-response gene Kr-h1 in a species-selective manner. The fourth chapter focuses on identification of direct JHR target genes during development of Drosophila melanogaster. In this model organism, we implemented a novel technique, targeted DamID, to profile genome-wide protein-DNA interactions of the JHR in a selected tissue. We reveal a previously unrecognized role of JH in Drosophila larval development and identify a gene mediating this role. Together, these findings contribute to better understanding of JH signaling and support development of safer, species-selective pest control tools.

Keywords

juvenile hormone, hormones, development, insect, genetics, molecular biology, DamID, Drosophila, insecticides, biochemistry

Jazyk práce: angličtina

Datum vytvoření / odevzdání či podání práce: 20. 3. 2026

Obhajoba závěrečné práce

• Obhajoba proběhla 22. 4. 2026
• Vedoucí: prof. RNDr. Marek Jindra, CSc.

JIHOČESKÁ UNIVERZITA V ČESKÝCH BUDĚJOVICÍCH

Přírodovědecká fakulta

Doktorský studijní program / obor:
Integrativní biologie / Integrativní biologie