Journal ArticleDOI
The cell cycle in Crithidia fasciculata. Temporal relationships between synthesis of deoxyribonucleic acid in the nucleus and in the kinetoplast.
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TLDR
The hypothesis is proposed that this synchrony results from the sharing by nucleus and kinetoplast of the same mechanism for the production of the deoxyribonucleotides used in replication of their respective DNAs.Abstract:
SYNOPSIS. Autoradiographic technics with tritium-labeled thymidine have been used to determine G1, S, G2 and D for the kinetoplast and the nucleus of Crithidia fasciculata at 15, 25 and 32 C. The kinetoplast completes division before the nucleus at all 3 temperatures. The S phases of both organelles occur in approximate synchrony and are approximately equal in length but the nucleus begins and completes S before the kinetoplast at the 2 lower temperatures. This relationship is reversed at 32 C. Most of the effect of temperature on generation time is due to its effect on the length of S.
The results are compared with similar studies on C. luciliae, Trypanosoma mega, other protozoa and tissue cells in culture. The role of the approximate synchrony of nuclear and kinetoplastic cycles in maintenance of the kinetoplastic condition is discussed and the hypothesis is proposed that this synchrony results from the sharing by nucleus and kinetoplast of the same mechanism for the production of the deoxyribonucleotides used in replication of their respective DNAs.read more
Citations
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Journal ArticleDOI
The cell division cycle of Trypanosoma brucei brucei: timing of event markers and cytoskeletal modulations.
Trevor Sherwin,Keith Gull +1 more
TL;DR: The timing and order of events occurring within the cell division cycle of Trypanosoma brucei has been derived from analyses of the proportion of a given cell type occurring witin an exponentially growing culture.
Journal ArticleDOI
Timing of nuclear and kinetoplast DNA replication and early morphological events in the cell cycle of Trypanosoma brucei
R. Woodward,K. Gull +1 more
TL;DR: Immunofluorescent detection of 5-bromo-2-deoxyuridine-substituted DNA is used to determine the timing of initiation and the duration of nuclear and kinetoplast S-phases within the procyclic stage of the Trypanosoma brucei cell cycle and provides detection of the earliest known cell cycle event in T. Brucei.
Journal ArticleDOI
A High-Order Trans-Membrane Structural Linkage Is Responsible for Mitochondrial Genome Positioning and Segregation by Flagellar Basal Bodies in Trypanosomes
TL;DR: Understanding of the high-order trans-membrane linkage provides an explanation for the spatial position of the trypanosome mitochondrial genome and its mechanism of segregation.
Journal ArticleDOI
Evidence for novel cell cycle checkpoints in trypanosomes: kinetoplast segregation and cytokinesis in the absence of mitosis.
TL;DR: It is shown that T. brucei cytokinesis is not dependent upon either mitosis or nuclear DNA synthesis, suggesting that there are novel cell cycle checkpoints in this organism.
Book ChapterDOI
The Kinetoplast of the Hernoflagellates
TL;DR: The existence of one mitochondrion per cell should be conclusively proved by the three-dimensional reconstruction technique and the replication of K-DNA should be investigated, both in terms of the intracellular regulatory mechanisms involved in the synchrony of the kinetoplast S period with the nuclear S period and the actual replication of the minicircles and long DNA molecules.
References
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Journal ArticleDOI
Hydroxyurea: inhibitory effect on dna metabolism.
Charles W. Young,Sadie Hodas +1 more
TL;DR: Hydxyurea, hydroxyurethane, and dihydroxyurea inhibit incorporation of thymidine into the DNA of monolayers of HeLa cells, but hydroxylamine inhibits cellular incorporation of all three precursors:Thymidine, uridine, and leucine.
Journal ArticleDOI
DNA synthesis in individual L-strain mouse cells
C.P. Stanners,James E. Till +1 more
TL;DR: The time relationship between DNA synthesis and mitosis has been determined for L-strain mouse cells cultivated in vitro and a mathematical treatment for exponentially multiplying cultures is presented.
Journal ArticleDOI
Biochemistry of the cell cycle: a review
TL;DR: A review of the literature suggests that the genome itself controls its own replication, and that this control is mediated through the synthesis of specific RNA and protein molecules.
Journal ArticleDOI
Nucleic acid metabolism in a slime mold with synchronous mitosis.
TL;DR: Preliminary experiments indicated that the mold was capable of converting orotic acid to thymine nucleotides throughout the interphase; this suggests that the control of DNA synthesis must occur at some point very close to the final polymerization of the molecule.
Journal ArticleDOI
The syntheses of total macronuclear protein, histone, and DNA during the cell cycle in Euplotes eurystomus
TL;DR: Radioautographic analysis showed that protein labeling occurs throughout the macronucleus during the entire life cycle, and the distribution of label suggests that most of macronuclear protein labeling during the cell cycle is concerned with the events of transcription rather than replication.
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Timing of nuclear and kinetoplast DNA replication and early morphological events in the cell cycle of Trypanosoma brucei
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