Protoplasma

, Volume 138, Issue 2–3, pp 105–118 | Cite as

Ultrastructure of mitosis and cytokinesis inZygnema sp. (Zygnematales, Chlorophyta)

  • M. E. Bakker
  • G. M. Lokhorst
Article

Summary

Mitosis and cytokinesis have been studied in the green algaZygnema C. A. Agardh using interference-contrast light and transmission electron microscopy. At prophase, the nucleolus disintegrates and numerous extranuclear microtubules near the nuclear periphery penetrate into the nucleoplasm. When aligned in the equatorial plane of the open metaphase spindle the chromosomes are coated with persistent nucleolar fragments. At anaphase, vacuoles intrude into the interzonal spindle region and seemingly contribute to the anaphase movement of the chromosomes. At telophase, the spindle is persistent and the reforming nuclei are separated by cytoplasmic strands containing microtubules, interspersed with vacuoles. Extensive bundles of microtubules, dictyosomes and parallel, slightly inflated ER-profiles extend from the poles of the telophase nucleus along the longitudinal side of the chloroplast. Conceivably, these microtubules guide the nucleus during its post-mitotic migration towards its central interphase position between the two halves of the dividing chloroplast. Throughout the mitotic cycle, ubiquitous dictyosomes, positioned near the chloroplast core, seem very active. Arrays of microtubules run towards these dictyosomes and may conduct the dictyosome-vesicles to the cleavage plane. At metaphase, septum growth becomes visible as an annular ingrowth of the plasmalemma. At late telophase or at entering interphase, an extensive clump of vesicles, associated with longitudinal bundles of microtubules, appears between the leading edges of the advanced furrow. Apparent fusion of these vesicles with the head of the centripetally-growing furrow results in its completion. The pattern of mitosis and cytokinesis inZygnema is compared with that of closely related green algae.

Keywords

Cytokinesis Green algae Microtubules Mitosis Zygnema 

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References

  1. Agardh CA (1924) Systema algarum. Ascher, AmsterdamGoogle Scholar
  2. Bakhuizen R, Spronsen PC van, Sluiman-den Hertog FAJ, Venverloo CJ, Goosen-de Roo L (1985) Nuclear envelope radiating microtubules in plant cells during interphase mitosis transition. Protoplasma 128: 43–51Google Scholar
  3. Barker ME, Lokhorst GM (1984) Ultrastructure ofDraparnaldia glomerata (Vauch.) Agardh (Chaetophorales; Chlorophyceae) I. The flagellar apparatus of the zoospore. Nord J Bot 4: 261–273Google Scholar
  4. Bech-Hansen CW, Fowke LC (1972) Mitosis inMougeotia sp. Can. J Bot 50: 1811–1816Google Scholar
  5. Burgess J (1970) Interactions between microtubules and the nuclear envelope during mitosis in a fern. Protoplasma 71: 77–89Google Scholar
  6. Chapman RL, Henk MC (1986) Phragmoplasts in cytokinesis ofCephaleuros parasitions (Chlorophyta) vegetative cells. J Phycol 22: 83–88Google Scholar
  7. Floyd GL, Stewart KD, Mattox KR (1972) Cellular organization, mitosis, and cytokinesis in the ulotrichalean algaKlebsormidium. J Phycol 8: 176–184Google Scholar
  8. Fowke LC, Pickett-Heaps JD (1969 a) Cell division inSpirogyra. I. Mitosis. J Phycol 5: 240–259Google Scholar
  9. — (1969 b) Cell division inSpirogyra. II. Cytokinesis. J Phycol 5: 273–281Google Scholar
  10. Gerlach D (1969) Botanische Mikrotechnik. Thieme, StuttgartGoogle Scholar
  11. Gunning BES (1982) The cytokinetic apparatus: its development and spatial regulation. In:Lloyd CW (ed) The cytoskeleton in plant growth and development. Academic Press, London, pp 229–292Google Scholar
  12. Harada A (1981) Cytological studies onSirogonium (Chlorophyceae). I. Mitosis inS. sticticum andS. melanosporum. Jpn J Phycol 29: 23–29Google Scholar
  13. Harada A, Yamagishi T (1980) Cytological studies onZygnema (Chlorophyceae). I. Mitosis. Jpn J Phycol 28: 233–239Google Scholar
  14. — (1984) Mitosis inSpirogyra (Chlorophyceae). Jpn J Phycol 32: 1–9Google Scholar
  15. Krupp JM, Lang NJ (1985 a) Cell division and filament formation in the desmidBambusina brebissonii (Chlorophyta). J Phycol 21: 16–25Google Scholar
  16. — (1985 b) Cell division and the role of the primary wall in the filamentous desmidOnychonema laeve. J Phycol 21: 316–322Google Scholar
  17. Lacalli TC (1973) Cytokinesis inMicrasterias rotata. Problems of directed primary wall deposition. Protoplasma 78: 433–442Google Scholar
  18. Lokhorst GM, Star W (1985) Ultrastructure of mitosis and cytokinesis inKlebsormidium mucosum nov. comb., formerlyUlothrix verrucosa (Chlorophyta). J Phycol 21: 466–476Google Scholar
  19. Marchant HJ, Pickett-Heaps JD (1973) Mitosis and cytokinesis inColeochaete scutata. J Phycol 9: 461–471Google Scholar
  20. McLean RJ, Pessoney GF (1971) Formation and resistance of akinetes ofZygnema. In:Parker BC, Brown RM (eds) Contributions in Phycology. A Press, Lawrence, Kansas, pp 146–152Google Scholar
  21. O'Kelly CJ, Floyd GL (1984) Correlations among patterns of sporangial structure and development, life histories and ultrastructural features in the Ulvophyceae. In:Irvine DEG, John DM (eds) Systematics of the Green Algae. Academic Press, London New York, pp 121–156Google Scholar
  22. Pickett-Heaps JD (1967) Ultrastructure and differentiation inChora sp. II. Mitosis. Austr J Biol Sci 20: 883–894Google Scholar
  23. — (1970) The behaviour of the nucleolus during mitosis in plants. Cytobios 2: 69–78Google Scholar
  24. — (1972) Cell division inCosmarium botrytis. J Phycol 8: 343–360Google Scholar
  25. — (1974) Cell division inStichococcus. Br Phycol J 9: 63–73Google Scholar
  26. — (1975) Green Algae. Structure, reproduction and evolution in selected genera. Sinauer, Sunderland, MassachusettsGoogle Scholar
  27. — (1976) Cell division inRaphidonema longiseta. Arch Protistenk 118: 209–214Google Scholar
  28. Pickett-Heaps JD, Fowke LC (1970) Mitosis, cytokinesis, and cell elongation in the desmidClosterium littorale. J Phycol 6: 189–215Google Scholar
  29. Pickett-Heaps JD, Marchant HJ (1972) The phylogeny of the green algae. A new proposal. Cytobios 6: 255–264Google Scholar
  30. Randhawa MS (1969)Zygnemaceae. Indian Council of Agricultural Research, New DelhiGoogle Scholar
  31. Stewart KD, Mattox KR (1975) Comparative cytology, evolution and classification of the Green Algae with some consideration of the origin of other organisms with chlorophylls a and b. Bot Rev 41: 104–135Google Scholar
  32. Turner FR (1968) An ultrastructural study of plant spermatogenesis: spermatogenesis inNitella. J Cell Biol 37: 370–393PubMedGoogle Scholar
  33. Wells CV, Hoshaw RW (1968) The nucleus and chromosomes ofSirogonium. J Phycol 4 [Suppl]: 5–6Google Scholar

Copyright information

© Springer-Verlag 1987

Authors and Affiliations

  • M. E. Bakker
    • 1
  • G. M. Lokhorst
    • 1
  1. 1.RijksherbariumRA LeidenThe Netherlands

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