Sven Klumpe, Kirsten A. Senti, Florian Beck, Jenny Sachweh, Bernhard Hampoelz, Paolo Ronchi, Viola Oorschot, Marlene Brandstetter, Assa Yeroslaviz, John A.G. Briggs, Julius Brennecke, Martin Beck, Jürgen M. Plitzko
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引用次数: 0
Abstract
Long terminal repeat (LTR) retrotransposons belong to the transposable elements (TEs), autonomously replicating genetic elements that integrate into the host’s genome. Among animals, Drosophila melanogaster serves as an important model organism for TE research and contains several LTR retrotransposons, including the Ty1-copia family, which is evolutionarily related to retroviruses and forms virus-like particles (VLPs). In this study, we use cryo-focused ion beam (FIB) milling and lift-out approaches to visualize copia VLPs in ovarian cells and intact egg chambers, resolving the in situ copia capsid structure to 7.7 Å resolution by cryoelectron tomography (cryo-ET). Although cytoplasmic copia VLPs vary in size, nuclear VLPs are homogeneous and form densely packed clusters, supporting a model in which nuclear import acts as a size selector. Analyzing flies deficient in the TE-suppressing PIWI-interacting RNA (piRNA) pathway, we observe copia’s translocation into the nucleus during spermatogenesis. Our findings provide insights into the replication cycle and cellular structural biology of an active LTR retrotransposon.
期刊介绍:
Cells is an international, peer-reviewed, open access journal that focuses on cell biology, molecular biology, and biophysics. It is affiliated with several societies, including the Spanish Society for Biochemistry and Molecular Biology (SEBBM), Nordic Autophagy Society (NAS), Spanish Society of Hematology and Hemotherapy (SEHH), and Society for Regenerative Medicine (Russian Federation) (RPO).
The journal publishes research findings of significant importance in various areas of experimental biology, such as cell biology, molecular biology, neuroscience, immunology, virology, microbiology, cancer, human genetics, systems biology, signaling, and disease mechanisms and therapeutics. The primary criterion for considering papers is whether the results contribute to significant conceptual advances or raise thought-provoking questions and hypotheses related to interesting and important biological inquiries.
In addition to primary research articles presented in four formats, Cells also features review and opinion articles in its "leading edge" section, discussing recent research advancements and topics of interest to its wide readership.