Related Experiment Video
Updated: Jun 9, 2026
06:53
Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
Circadian clock genes, ovarian development and diapause.
William E Bradshaw1, Christina M Holzapfel
1Center for Ecology and Evolutionary Biology, University of Oregon, Eugene, OR 97403-5289, USA.
BMC Biology
|September 11, 2010
Summary
The study reveals that altering circadian clock genes, period and cycle, impacts ovarian diapause in the insect Riptortus pedestris. This finding supports the hypothesis that the circadian clock underlies seasonal photoperiodism in insects.
Area of Science:
- Entomology
- Chronobiology
- Genetics
Background:
- Insects possess a circadian clock regulating daily rhythms and a seasonal timing mechanism for events like diapause.
- The study investigates the role of circadian clock genes in mediating seasonal responses in insects.
Discussion:
- Ikeno et al. demonstrated that downregulating period and cycle genes affects ovarian diapause in Riptortus pedestris.
- This provides evidence supporting Erwin Bünning's hypothesis linking the circadian clock to photoperiodism.
- Alternative explanations, such as pleiotropic effects of clock genes, are also considered.
Key Insights:
- Circadian clock genes, specifically period and cycle, are implicated in the regulation of insect diapause.
- The findings support the long-standing hypothesis that the circadian clock is fundamental to photoperiodism.
- The research highlights the intricate connection between daily rhythms and seasonal adaptations in insects.
Outlook:
- Further research is needed to elucidate the precise molecular mechanisms.
- Investigating potential pleiotropic effects of clock genes on diapause is warranted.
- Understanding these mechanisms can inform pest management strategies and conservation efforts.
Related Concept Videos
02:19Circadian Rhythms and Gene Regulation
The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...
02:19Circadian Rhythms and Gene Regulation
The biological clock is involved in many aspects of regulating complex physiology in all animals. It was in 1935 when German zoologists, Hans Kalmus and Erwin Bünning, discovered the existence of circadian rhythm in Drosophila melanogaster. However, the internal molecular mechanisms behind the circadian clock remained a mystery until 1984, when Jeffrey C. Hall, Michael Rosbash, and Michael W. Young discovered the expression of the Per gene oscillating over a 24-hour cycle. In subsequent years,...
02:45Biological Clocks and Seasonal Responses
The circadian—or biological—clock is an intrinsic, timekeeping, molecular mechanism that allows plants to coordinate physiological activities over 24-hour cycles called circadian rhythms. Photoperiodism is a collective term for the biological responses of plants to variations in the relative lengths of dark and light periods. The period of light-exposure is called the photoperiod.
02:27Background and Environment Affect Phenotype
Although the genetic makeup of an organism plays a major role in determining the phenotype, there are also several environmental factors, such as temperature, oxygen availability, presence of mutagens, that can alter an organism’s phenotype.
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
01:30Hormonal Control of the Ovarian Cycle
The ovarian cycle is meticulously regulated by the hypothalamic-pituitary-gonadal axis. This cycle orchestrates the release of a mature oocyte, essential for reproduction.
Before puberty, the hypothalamus releases GnRH in a low frequency, low amplitude pulsatile manner. This along with the immature hypothalamic-pituitary-gonadal axis activity, results in low estrogen levels and the absence of a fully functional ovarian cycle. At puberty, GnRH secretion increases in both frequency and...
Before puberty, the hypothalamus releases GnRH in a low frequency, low amplitude pulsatile manner. This along with the immature hypothalamic-pituitary-gonadal axis activity, results in low estrogen levels and the absence of a fully functional ovarian cycle. At puberty, GnRH secretion increases in both frequency and...
02:07Oogenesis
In human women, oogenesis produces one mature egg cell or ovum for every precursor cell that enters meiosis. This process differs in two unique ways from the equivalent procedure of spermatogenesis in males. First, meiotic divisions during oogenesis are asymmetric, meaning that a large oocyte (containing most of the cytoplasm) and minor polar body are produced as a result of meiosis I, and again following meiosis II. Since only oocytes will go on to form embryos if fertilized, this unequal...