timeless2 plays an important role in reproduction and circadian rhythms in the cricket Gryllus bimaculatus

Dec 31, 2017Journal of insect physiology

The timeless2 gene influences reproduction and daily biological rhythms in the cricket Gryllus bimaculatus

AI simplified

Circadian Biology on OpenScience ↗PubMed ↗DOI ↗

Abstract

Treatment with Gb'tim2 resulted in less than 2% egg hatching success compared to 70% in control eggs.

Gb'tim2 encodes a protein with approximately 65% similarity to the Drosophila Timeless protein.
Development of most embryos treated with Gb'tim2 was arrested in early stages.
Egg production in ovaries of adult virgin females treated with Gb'tim2 was significantly reduced.
Gb'tim2 crickets displayed a weakened locomotor rhythm synchronized with light cycles.
Under constant darkness, the activity rhythm of Gb'tim2 crickets often split into two components with different periods.
Molecular analysis indicated that Gb'tim2 treatment downregulated mRNA levels of Gb'per and Gb'Clk while enhancing Gb'cyc rhythm.

AI simplified

The timeless2 (tim2) gene is an insect orthologue of the mammalian clock gene Timeless (mTim). Although its functional role has been extensively studied in mammals, little is known regarding its role in insects. In the present study, we obtained tim2 cDNA (Gb'tim2) from the cricket Gryllus bimaculatus and characterized its functional role in embryonic development, egg production, and circadian rhythms. Gb'tim2 gave rise to a 1432 amino acid protein, and showed approximately 65% homology to that of Drosophila melanogaster. When treated with parental Gb'tim2, less than 2% of the treated eggs hatched. On the other hand, control eggs treated with DsRed2demonstrated a hatching rate of 70%. In most of the Gb'tim2treated embryos, development was arrested in early stages. Egg production in ovaries of adult virgin females treated with Gb'tim2was significantly reduced. In addition, while Gb'tim2crickets exhibited clear locomotor rhythm synchronized with light cycles, their light-on peak was weaker than that of control crickets. Under constant darkness, the activity rhythm of Gb'tim2crickets was often split into two components running with different periods. Molecular analysis revealed that Gb'tim2treatment downregulated mRNA levels of Gb'per and Gb'Clk, and enhanced Gb'cyc expression rhythm; no distinct effect was found on Gb'tim expression levels. The change in Gb'per, Gb'Clk and Gb'cyc levels may underlie the altered behavioral rhythms in Gb'tim2crickets. Both Gb'Clkand Gb'cycdownregulated Gb'tim2 expression, which suggested that transcription of Gb'tim2 is mediated by Gb'CLK and Gb'CYC through E-box. These results suggested that Gb'tim2 may be involved in both reproduction and circadian rhythm regulation in crickets. RNAi RNAi RNAi RNAi RNAi RNAi RNAi RNAi RNAi RNAi

Full Text

Full text is available at the source.

View full text (XML) ↗View full text ↗

timeless2 plays an important role in reproduction and circadian rhythms in the cricket Gryllus bimaculatus

Abstract

Full Text

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the circadian biology brief

Abstract

Full Text

Related papers

You found one interesting study. We’ll send the next 7.

what lands in your inbox each week:

Recent issues from the circadian biology brief