Summary
The portion of the life cycle ofAcetabularia mediterranea from cyst formation to gamete release is described. During maturation, the cyst nucleus undergoes a series of mitoses in which the nuclear membrane remains intact, and the spindle microtubules are confined to the intranuclear space. There is a dark requirement for the completion of cyst maturation at the end of which the nuclei are in groups and centrioles are present. The final migration of the nuclei, cleavage of the cytoplasm into gametes, and the development of flagella is cxtremely rapid, taking six to twelve hours. Cysts which fail to germinate are blocked at a late stage in the maturation process, either before or after the final nuclear division.
The observations are related to mitosis in other green algae (Chlorophyceae) and to gametogenesis inBryopsis hypnoides. Changes in the amount and distribution of heterochromatin in the nuclei are discussed in relation to the life cycle ofA. mediterranea.
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References
Brown, S. W., 1966: Heterochromatin. Science151, 417–425.
Burr, F. A., andJ. A. West, 1970: Light and electron microscope observations on the vegetative and reproductive structures ofBryopsis hypnoides. Phycologia9, 17–37.
Crawley, J. C., 1966: Some observations on the fine structure of the gametes and zygotes ofAcetabularia. Planta69, 365–376.
—, 1970: The fine structure of the gametes and zygotes ofAcetabularia. In: Biology ofAcetabularia (J. Brachet andS. Bonotto, eds.). London and New York: Academic Press.
Fowke, L. C., andJ. D. Pickett-Heaps, 1969: Cell division inSpirogyra; I. Mitosis. J. Phycol.5, 240–259.
Johnson, U. G., andK. R. Porter, 1968: Fine structure of cell division inChlamydomonas reinhardi. J. Cell Biol.38, 403–425.
Lateur, L., 1963: Une technique de culture pour l'Acetabularia mediterranea. Rev. Algol.1, 26–37.
- 1971: Personal communication.
Pickett-Heaps, J. D., andL. C. Fowke, 1970: Cell division inOedogonium. II. Nuclear division inO. cardiacum. Aust. J. Biol. Sci.23, 71–92.
Puiseux-Dao, S., 1962: Recherches biologiques et physiologiques sur quelques Dasycladacées. Rev. Gén. Bot.819, 409–503.
—, 1963: Les Acetabulaires, matérial de laboratoire. L'Année Biol. II 3–4, 99–154.
—, 1966: The nucleus of theSiphonales andSiphonocladales. In: The chromosomes of the algae (M. B. E. Godward, ed.). London: Edward Arnold.
Schultze, K. L., 1939: Cytologische Untersuchungen anAcetabularia mediterranea undAcetabularia wettsteinii. Arch. Protistenk.92, 179–225.
Wik-Sjostedt, 1970: Cytogenetic investigations inCladophora. Hereditas66, 233–269.
Woodcock, C. L. F., 1971: The anchoring of nuclei by cytoplasmic microtubules inAcetabularia. J. Cell Sci.8, 611–621.
—, andP. R. Bell, 1967: A method for mounting four micron resin sections routinely for ultra-thin sectioning. J. R. Microsc. Soc.87 485–488.
—, andG. J. Miller, 1973: Ultrastructural features of the life cycle ofAcetabularia mediterranea. II. Events associated with the division of the primary nucleus and the formation of cysts. Protoplasma77, 331–341.
Yunis, J. J., andW. G. Yasmineh, 1971: Heterochromatin, satellite DNA and cell function. Science174, 1200–1209.
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Supported in part by Grant GM 06637 from the U.S. Public Health Service.
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Woodcock, C.L.F., Miller, G.J. Ultrastructural features of the life cycle ofAcetabularia mediterranea . Protoplasma 77, 313–329 (1973). https://doi.org/10.1007/BF01276766
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DOI: https://doi.org/10.1007/BF01276766