spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by MURRIN, F.
Right arrow Articles by HEATH, I. B.
Right arrow Search for Related Content
PubMed
Right arrow Articles by MURRIN, F.
Right arrow Articles by HEATH, I. B.

Journal of Cell Science, Vol 90, 501-516, Copyright © 1988 by Company of Biologists

Submitted on September 2, 1987
Accepted on March 28, 1988

The ultrastructure and timing of events in the nuclear cycle of the fungus Entomophaga aulicae

FAYE MURRIN 1, WILLIAM NEWCOMB 1, and I. BRENT HEATH 2

1 Department of Biology, Queen's University, Kingston, Ontario, K7L 3N6, Canada
2 Department of Biology, York University, North York, Ontario, M3J 1P3, Canada

Present address, for correspondence: Department of Biology, Memorial University of Newfoundland, St John's, Newfoundland, MB 3N9, Canada

The ultrastructure of the mitotic nuclear division cycle of the fungus Entomophaga aulicae was studied from serial sections of hyphal tips and protoplasts. The extranuclear bar-shaped nucleus- associated organelle (NAO) remained associated with the persistent nuclear envelope throughout. Prior to spindle formation, a patch of intranuclear NAO-associated chromatin detached from the nuclear envelope to yield a chromatin free zone containing fine filaments and a linear array of presumptive kinetochores. Early metaphase spindles less than 1µm in length were characterized by a ‘fused’ metaphase plate consisting of kinetochore-associated chromatin and a full complement of at least 15 kinetochore microtubules per half-spindle, while most of the chromatin was remote from the intranuclear spindle. Analysis of the distribution of antiparallel spindle microtubules indicated that polar separation and concomitant spindle elongation through metaphase were not accompanied by intermicrotubule sliding. Anaphase exhibited extensive decondensation of the large patches of condensed chromatin characteristic of all other stages. In a logarithmically growing protoplast population all nuclei contained spindle microtubules, with metaphase occupying approximately 66% of the nuclear cycle time. The calculated genome size of 4.3 pg, and average DNA content per chromosome of 0.3 pg, are extremely high for fungi.

Key words: fungal nucleus, nuclear cycle, spindle ultrastructure, mitosis

Submitted on September 2, 1987
Accepted on March 28, 1988




This article has been cited by other articles:


Home page
 Microbiol. Mol. Biol. Rev.Home page
A. E. Hajek
Pathology and Epizootiology of Entomophaga maimaiga Infections in Forest Lepidoptera
Microbiol. Mol. Biol. Rev., December 1, 1999; 63(4): 814 - 835.
[Abstract] [Full Text] [PDF]


© The Company of Biologists Ltd 1988