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Abstract Linear chromosomes shorten in every round of replication. InDrosophila, telomere‐specialized long interspersed retrotransposable elements (LINEs) belonging to the jockey clade offset this shortening by forming head‐to‐tail arrays atDrosophilatelomere ends. As such, these telomeric LINEs have been considered adaptive symbionts of the genome, protecting it from premature decay, particularly asDrosophilalacks a conventional telomerase holoenzyme. However, as reviewed here, recent work reveals a high degree of variation and turnover in the telomere‐specialized LINE lineages acrossDrosophila. There appears to be no absolute requirement for LINE activity to maintain telomeres in flies, hence the suggestion that the telomere‐specialized LINEs may instead be neutral or in conflict with the host, rather than adaptive.
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Plant telomere biology: The green solution to the end-replication problem
Abstract Telomere maintenance is a fundamental cellular process conserved across all eukaryotic lineages. Although plants and animals diverged over 1.5 billion years ago, lessons learned from plants continue to push the boundaries of science, revealing detailed molecular mechanisms in telomere biology with broad implications for human health, aging biology, and stress responses. Recent studies of plant telomeres have unveiled unexpected divergence in telomere sequence and architecture, and the proteins that engage telomeric DNA and telomerase. The discovery of telomerase RNA components in the plant kingdom and some algae groups revealed new insight into the divergent evolution and the universal core of telomerase across major eukaryotic kingdoms. In addition, resources cataloging the abundant natural variation in Arabidopsis thaliana, maize (Zea mays), and other plants are providing unparalleled opportunities to understand the genetic networks that govern telomere length polymorphism and, as a result, are uncovering unanticipated crosstalk between telomeres, environmental factors, organismal fitness, and plant physiology. Here we recap current advances in plant telomere biology and put this field in perspective relative to telomere and telomerase research in other eukaryotic lineages.
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- PAR ID:
- 10368572
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- The Plant Cell
- Volume:
- 34
- Issue:
- 7
- ISSN:
- 1040-4651
- Format(s):
- Medium: X Size: p. 2492-2504
- Size(s):
- p. 2492-2504
- Sponsoring Org:
- National Science Foundation
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