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Plant microtubule-organizing centers
Škrdlová, Iveta ; Schwarzerová, Kateřina (advisor) ; Libusová, Lenka (referee)
In eukaryotic cells, microtubules are nucleated and organized by protein structures called microtubule- organizing centers. There is a great diversity in structure and morphology of these structures in eukaryotic organisms. Animal centrosome, yeast spindle pole body and basal bodies of flagellar apparatus are the best known types of so called focused microtubule-organizing centers, where microtubules are nucleated from one or two concrete sites in the cell. These focused microtubule- organizing centers are replaced by diffuse centers in higher plant cells, which means that microtubules are nucleated from dispersed nucleation sites. Focused centers are rarely found in land plant cells. These focused centers comprise bicentrioles and blepharoplasts, which give rise to the locomotory apparatus of motile spermatozoid of bryophytes, pteridophytes, cycads and Ginkgo. Another types of focused microtubule-organizing centers in bryophytes are polar organizers, and the nuclear and the plastid envelopes in mitotic and meiotic cells. Powered by TCPDF (www.tcpdf.org)
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