Direct evidence for the presence of DNA in interbands of Drosophila salivary gland chromosomes.
نویسنده
چکیده
F R O M the results of experiments involving autoradiography of stretched H3 thymidine-labelled salivary gland chromosomes of Drosophila melanogaster, and a consideration of previously published evidence, STEFFENSEN (1963) has concluded that DNA (deoxyribonucleic acid) is absent from the interband regions of these chromosomes. In opposition to this conclusion are the results presented in this report of examinations in the fluorescence microscope of acridine orange stained, ribonuclease digested salivary glands of Drosophila melanogaster, which provide direct evidence for the presence of DNA in interband regions of polytene chromosomes.
منابع مشابه
Identical Functional Organization of Nonpolytene and Polytene Chromosomes in Drosophila melanogaster
Salivary gland polytene chromosomes demonstrate banding pattern, genetic meaning of which is an enigma for decades. Till now it is not known how to mark the band/interband borders on physical map of DNA and structures of polytene chromosomes are not characterized in molecular and genetic terms. It is not known either similar banding pattern exists in chromosomes of regular diploid mitotically d...
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ورودعنوان ژورنال:
- Genetics
دوره 53 2 شماره
صفحات -
تاریخ انتشار 1966