|Cancer||Cell death||Cell cycle||Cytoskeleton||Exo/endocytosis||Differentiation||Division||Organelles||Signalling||Stem cells||Trafficking|
Cell Biology International (1993) 17, 153168 (Printed in Great Britain)
Cytoskeletal changes and induction of embryogenesis in microspore and pollen cultures of Brassica napus L.
B. Hause, G. Hause, P. Pechan and A.A.M. Van Lammeren
Wageningen Agricultural University, Department of Plant Cytology and Morphology, Arboretumlaan 4, NL-6703 BD Wageningen, The Netherlands; Max-Planck-Institut für Züchtungsforschung, DW-5000 Köln 30, Federal Republic of Germany and Martin-Luther Universität Halle, Institut für Genetik DO-4020 Halle, Federal Republic of Germany
Microspores and pollen of Brassica napus were cultured under conditions leading to embryo formation. Concomitant changes in cytoskeletal configurations were analysed. The microfilamental cytoskeleton exhibited a loss of polarity in embryogenic cells but cytochalasin treatment revealed that microfilaments do not influence embryogenesis. Two embryogenic pathways started from microspores and were either characterized by turned division planes or by division when the nucleus was in the cell centre. In both cases microtubules clearly exhibited new arrangements and likely played a major role in newly induced symmetrical division. In pollen, embryogenic development started in the vegetative cell provided the generative cell was arrested near the pollen wall. The concomitant disappearance of defined microtubular arrays is likely to be responsible for the positioning of the cell.