Summary
The organization of the microtubule cytoskeleton in the generative cell ofConvallaria majalis has been studied during migration of the cell through the pollen tube and its division into the two sperm cells. Analysis by conventional or confocal laser scanning microscopy after tubulin staining was used to investigate changes of the microtubule cytoskeleton during generative-cell migration and division in the pollen tube. Staining of DNA with 4′,6-diamidino-2-phenylindole was used to correlate the rearrangement of microtubules with nuclear division during sperm cell formation. Before pollen germination the generative cell is spindle-shaped, with microtubules organized in bundles and distributed in the cell cortex to form a basketlike structure beneath the generative-cell plasma membrane. During generative-cell migration through the pollen tube, the organization of the microtubule bundles changes following nuclear division. A typical metaphase plate is not usually formed. The generative-cell division is characterized by the extension of microtubules concomitant with a significant cell elongation. After karyokinesis, microtubule bundles reorganize to form a phragmoplast between the two sperm nuclei. The microtubule organization during generative-cell division inConvallaria majalis shows some similarities but also differences to that in other members of the Liliaceae.
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Abbreviations
- CLSM:
-
confocal laser scanning microscopy
- EM:
-
electron microscopy
- GC:
-
generative cell
- GN:
-
generative nucleus
- MT:
-
microtubule
- SC:
-
sperm cell
- SN:
-
sperm nucleus
- VN:
-
vegetative nucleus
References
Banas M, Tirlapur UK, Charzynska M, Cresti M (1996) Some events of mitosis and cytokinesis in the generative cell ofOrnithogalum virens L. Planta 199: 202–208
Bohdanowicz J, Ciampolini F, Cresti M (1995) Striped projections of the outer membrane of the generative cell inConvallaria majalis. Sex Plant Reprod 8: 223–227
Brewbaker JL, Kwack BH (1963) The essential role of calcium ion in pollen germination and pollen tube growth. Am J Bot 50: 859–865
Burgess J (1970) Cell shape and mitotic spindle formation in the generative cell ofEndymion non-scriptus. Planta 95: 72–85
Cai X, Hu SY (1996) Changes of microtubular skeleton in the generative cell in pollen tube during mitosis ofLilium davidii. Acta Bot Sin 38: 761–766
Charzynska M, Cresti M (1993) Early events in division of the generative cell ofOrnithogalum virens. Protoplasma 172: 77–83
Cooper DC (1936) Development of the male gametes ofLilium. Bot Gaz 98: 169–177
Del Casino C, Tiezzi A, Wagner VT, Cresti M (1992) The organization of the cytoskeleton in the generative cell and sperms ofHyacinthus orientalis. Protoplasma 168: 41–50
Johnston GW (1941) Cytological studies of male gamete formation in certain angiosperms. Am J Bot 28: 306–319
Ning L, Fu-Xiong W, Zu-Keng C (1991) Ultrastructure of sperm cells inOphiopogon japonicus. Chin J Bot 3: 97–101
O'Mara JG (1933) Division of the generative nucleus in the pollen tube ofLilium. Bot Gaz 94: 567–578
Palevitz BA (1990) Kinetochore behavior during generative cell division inTradescantia virginiana. Protoplasma 157: 120–127
— (1993) Morphological plasticity of the mitotic apparatus in plants and its developmental consequences. Plant Cell 5: 1001–1009
— (1989) Cytoskeletal changes during generative cell division and sperm formation inTradescantia virginiana. Protoplasma 150: 54–71
—, Tiezzi A (1992) Organization, composition and function of the generative cell and sperm cytoskeleton. Int Rev Cytol 140: 149–185
Sax K, O'Mara JG (1941) Mechanism of mitosis in pollen tubes. Bot Gaz 102: 629–636
Terasaka O, Niitsu T (1989) Peculiar spindle configuration in the generative cell ofTradescantia paludosa by immunofluorescence method. J Jpn Pollen Assoc 35: 7–12
Yu HS, Russell SD (1993) Three-dimensional ultrastructure of generative cell mitosis in the pollen tube ofNicotiana tabacum. Eur J Cell Biol 61: 338–348
Zee SY (1992) Confocal laser scanning microscopy of microtubule organization changes in isolated generative cells ofAllemanda neriifolia during mitosis. Sex Plant Reprod 5: 182–188
—, Zhu C, Hu SY (1990) Changes in the organization of microtubules during cell division and sperm formation inLilium. Acta Bot Sin 32: 821–826
Zhang H-Q, Bohdanowicz J, Pierson ES, Li Y-Q, Tiezzi A, Cresti M (1995) Microtubular organization during asymmetrical division of the generative cell inGagea lutea. J Plant Res 108: 269–276
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Del Casino, C., Bohdanowicz, J., Lewandowska, B. et al. The organization of microtubules during generative-cell division inConvallaria majalis . Protoplasma 207, 147–153 (1999). https://doi.org/10.1007/BF01282994
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DOI: https://doi.org/10.1007/BF01282994