Chapter category: Gene Expression
Telomeres in Drosophila and Other Insects
Telomerases, Telomeres and Cancer
Edited by: Guido Krupp and Reza ParwareschISBN: 0-306-47437-9
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Chapter authors:
Harald Biessmann, Marika F. Walter and James M. Mason
Of the vast numbers of insect species from many orders, only a few have been investigated for telomere structure. However, these studies have revealed the presence of three different types of telomere elongation mechanisms, two of which are also found in other eukaryotes (telomerase and recombination), and one novel mechanism (retrotransposition) that has so far only been found in Drosophila melanogaster and its close relatives. Drosophila melanogaster uses transposition of telomere-specific retrotransposons, HeT-A and TART, instead of telomerase to elongate its telomeres. Thus, its telomere structure differs from that of mammals and other eukaryotes. By studying the mechanisms that control telomere elongation in Drosophila and comparing them to those that regulate telomerase in mammals and yeast, some basic regulatory principles of telomere biology that are common to all eukaryotes may be uncovered. Progress has been made in defining intermediate steps of HeT-A transposition and in elucidating how they are affected by normal and induced cell proliferation, telomere interactions, and genetic background. In this article, we summarize the current knowledge of Drosophila telomeric retrotransposons and telomere elongation mechanisms in other insects, and contrast the findings with telomerase-mediated telomere elongation in other eukaryotes. We also describe protection, or "capping", of chromosome ends and telomeric silencing in Drosophila, which complements parallel research in yeast and vertebrates.
Additional chapters from this book:
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Telomeres in Drosophila and Other Insects
Harald Biessmann, Marika F. Walter and James M. Mason
Of the vast numbers of insect species from many orders, only a few have been investigated for telomere structure. However, these studies have revealed the presence of three different types of ...
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More than half a century ago, the pioneer of radiation genetics, Herman Joseph Muller, proposed that specialized structures, he termed telomeres, must be present at chromosome ends to ...
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