Nuclear Receptor FTZ-F1 Controls Locust Molt by Regulating the Molting Process of Locusta migratoria

Area of Science:

• Molecular Biology
• Entomology
• Developmental Biology

Background:

• Fushi-tarazu factor 1 (FTZ-F1) are nuclear receptor transcription factors vital for insect molting.
• The specific roles of FTZ-F1 in the molting process of the migratory locust, *Locusta migratoria*, remain largely uncharacterized.

Purpose of the Study:

• To identify and characterize FTZ-F1 transcripts in *Locusta migratoria*.
• To elucidate the function of these FTZ-F1 genes in the molting and ecdysis processes of locust nymphs.

Main Methods:

• Identification of two FTZ-F1 transcripts (*LmFTZ-F1-X1* and *LmFTZ-F1-X2*) in *L. migratoria*.
• Expression analysis using reverse-transcription quantitative polymerase chain reaction (RT-qPCR).
• Functional analysis via RNA interference (RNAi) targeting *LmFTZ-F1-X1* and *LmFTZ-F1-X2*.
• Cuticle analysis using hematoxylin-eosin and chitin staining.
• Gene expression profiling using RNA-sequencing (RNA-seq).

Main Results:

• *LmFTZ-F1-X1* and *LmFTZ-F1-X2* were highly expressed in the integument.
• Simultaneous silencing of both *LmFTZ-F1* genes arrested nymph development at the third instar stage, leading to mortality.
• Silencing resulted in thickened cuticles and differential expression of genes involved in cuticle formation, chitin synthesis, and cytochrome P450 activity.

Conclusions:

• *LmFTZ-F1-X1* and *LmFTZ-F1-X2* play essential, likely redundant, roles in locust ecdysis.
• These genes may regulate molting by controlling the expression of genes critical for cuticle synthesis and integrity.