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RNA interference of the period gene affects the rhythm of sperm release in moths

Joanna Kotwica1, Piotr Bebas, Barbara O Gvakharia

  • 1Department of Animal Physiology, Faculty of Biology, University of Warsaw, Warsaw, Poland.

Journal of Biological Rhythms
|January 20, 2009
PubMed

Insights

The period (per) gene regulates daily rhythms in moths. Disrupting per gene expression in Spodoptera littoralis delayed rhythmic sperm release, confirming its essential role in this reproductive clock.

Area of Science:

  • Chronobiology
  • Insect reproductive physiology
  • Molecular genetics

Background:

  • The period (per) gene is a key component of circadian clocks in many animals.
  • PER protein and mRNA exhibit daily oscillations in Drosophila melanogaster, regulating clock function.
  • The specific role of the per gene in generating output rhythms is unclear in most insect species.

Purpose of the Study:

  • To investigate the functional involvement of the per gene in the circadian rhythm of sperm release in the moth, Spodoptera littoralis.
  • To examine the expression patterns of per mRNA and PER protein in relevant reproductive tissues.

Main Methods:

  • Studied per mRNA and PER protein expression in cyst cells and barrier cells of Spodoptera littoralis testes.
  • Observed PER localization in light/dark cycles and constant darkness.
  • Utilized in vitro RNA interference (RNAi) with double-stranded per mRNA (dsRNA) to reduce per expression.

Main Results:

  • PER protein exhibited distinct localization patterns in cyst cells (nuclear in LD, cytoplasmic in DD) and barrier cells (nuclear in both LD and DD).
  • RNAi-mediated knockdown of per significantly reduced per mRNA and protein levels in both cell types.
  • Disruption of per expression led to a significant delay in the rhythmic release of sperm.

Conclusions:

  • The period gene is functionally involved in regulating the circadian rhythm of sperm release in Spodoptera littoralis.
  • A molecular oscillator involving the period gene plays a crucial role in the timing of reproductive events in this moth species.

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