Ultrastructure and Dynamics of Synaptonemal Complex Components During Meiotic Pairing and Synapsis of Standard (A) and Accessory (B) Rye Chromosomes
| Autor: | Christian J. Keijzer, E. I. Mikhailova, Susann Hesse, Mateusz Zelkowski, Andreas Houben, Veit Schubert |
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| Rok vydání: | 2019 |
| Předmět: |
0106 biological sciences
Plant Science lcsh:Plant culture 01 natural sciences CENH3 03 medical and health sciences Prophase Meiosis super-resolution microscopy Secale cereale Homologous chromosome meiosis lcsh:SB1-1110 Original Research 030304 developmental biology Anaphase 0303 health sciences B chromosome B chromosomes Chemistry synaptonemal complex Synapsis recombination Cell biology Synaptonemal complex Premature chromosome condensation scanning electron microscopy 010606 plant biology & botany |
| Zdroj: | Frontiers in Plant Science, Vol 10 (2019) Frontiers in Plant Science |
| ISSN: | 1664-462X |
| Popis: | During prophase I a meiosis-specific proteinaceous tripartite structure, the synaptonemal complex (SC), forms a scaffold to connect homologous chromosomes along their lengths. This process, called synapsis, is required in most organisms to promote recombination between homologs facilitating genetic variability and correct chromosome segregations during anaphase I. Recent studies in various organisms ranging from yeast to mammals identified several proteins involved in SC formation. However, the process of SC disassembly remains largely enigmatic. In this study we determined the structural changes during SC formation and disassembly in rye meiocytes containing accessory (B) chromosomes. The use of electron and super-resolution microscopy (3D-SIM) combined with immunohistochemistry and FISH allowed us to monitor the structural changes during prophase I. Visualization of the proteins ASY1, ZYP1, NSE4A, and HEI10 revealed an extensive SC remodeling during prophase I. The ultrastructural investigations of the dynamics of these four proteins showed that the SC disassembly is accompanied by the retraction of the lateral and axial elements from the central region of the SC. In addition, SC fragmentation and the formation of ball-like SC structures occur at late diakinesis. Moreover, we show that the SC composition of rye B chromosomes does not differ from that of the standard (A) chromosome complement. Our ultrastructural investigations indicate that the dynamic behavior of the studied proteins is involved in SC formation and synapsis. In addition, they fulfill also functions during desynapsis and chromosome condensation to realize proper recombination and homolog separation. We propose a model for the homologous chromosome behavior during prophase I based on the observed dynamics of ASY1, ZYP1, NSE4A, and HEI10. |
| Databáze: | OpenAIRE |
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