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DEVELOPMENT OF EYE COLORS IN DROSOPHILA: SOME PROPERTIES OF THE HORMONES CONCERNED
1School of Biological Sciences, Stanford University.
The Journal of General Physiology
|October 30, 2009
Summary
Researchers identified a hormone in Drosophila melanogaster that controls eye pigment. A simple extraction method was developed, and a quantitative assay was established based on its logarithmic relationship with eye color intensity.
Area of Science:
- Biochemistry
- Genetics
- Developmental Biology
Background:
- Pigment production in Drosophila melanogaster mutants is regulated by a specific substance.
- Understanding this substance is crucial for genetic and developmental studies.
Purpose of the Study:
- To characterize the chemical properties and activity of the pigment-inducing hormone.
- To develop a method for hormone extraction and quantification.
Main Methods:
- Extraction of the hormone from dried wild type Drosophila pupae using ethyl alcohol and water.
- Assay of hormone activity based on induced eye color in vermilion brown mutants.
- Determination of chemical properties including stability, solubility, and molecular weight.
Main Results:
- A stable, hormone-like substance inducing eye pigment was isolated.
- A logarithmic relationship between hormone amount and eye color was established, enabling quantitative determination.
- An intracellular enzyme inactivating the hormone in the presence of oxygen was identified.
- The hormone is amphoteric, with a molecular weight of 400-600, and exhibits amino acid-like properties but has a complex structure.
Conclusions:
- The study successfully isolated and characterized a key hormone regulating eye pigmentation in Drosophila melanogaster.
- The developed quantitative method allows for precise measurement of hormone concentration.
- The hormone's complex structure and enzymatic inactivation mechanism provide insights into developmental regulation.
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