## Abstract The DNA puff __BhC4β1__ gene of the sciarid __Bradysia hygida__ is induced in salivary glands prior to the pupal molt as a secondary response to the increase in ecdysone titers. Previous studies demonstrated that the __BhC4β1__ promoter is activated in transgenic __Drosophila melanogast
Puff development and DNA synthesis in Sciara salivary gland chromosomes in tissue culture
β Scribed by Cannon, Grace B.
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1965
- Tongue
- English
- Weight
- 1023 KB
- Volume
- 65
- Category
- Article
- ISSN
- 0095-9898
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β¦ Synopsis
A method for the tissue culture of salivary glands of Sciara coprophila in a chemically defined medium is presented. When the chromosomes of the posterior Iobe of the gland have puffs and the chromosomes of the anterior lobe do not have puffs prior to culture, puffs will develop in the anterior lobe chromosomes within a. 24 hour culture period. When these chromosome I1 puffs are at their largest, fully extended state and a bulb on chromosome I11 is in a larva nearing pupation, the puffs and bulb become condensed in culture more rapidly than in normal development. This condensed state of the chromatin is thought to be heterochromatin. The uptake of tritiated thymidine was compared in homologous glands of 20 larvae in six different stages of development and all glands were labeled before and after culture, indicating that the culture method does not interfere with DNA synthesis.
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