The life cycle of mitochondria in the true slime mould,Physarum polycephalum

Kawano, Shigeyuki

doi:10.1007/bf02493406

Cited by 16 publications

(6 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Physarum polycephalum (Kawano et al 1983, Kawano 1991. Kuroiwa et al (1981b) have reported that the DNA content of plastids increases remarkably during germination in higher plants.…”

Section: Discussionmentioning

confidence: 99%

Changes in Plastid DNA Content during the Life Cycle of the Hornwort Anthoceros punctatus L.

Izumil

Ono

1999

CYTOLOGIA

View full text Add to dashboard Cite

SummaryThe plastid DNA contents of egg, sperm, sporophyte, and gametophyte cells were measured to clarify the relative changes in plastid DNA content during the life cycle of the hornwort Anthoceros punctatus. Samples stained with DAPI were observed using epifluorescence microscopy and CHIAS. The plastid DNA content of unfertilized egg cells did not change before and the fertilization because of preferential digestion of organelle DNA in sperm cells. In the 2n-generation, plastids multiplied by binary fission, with DNA duplication. It is thought that plastid DNA content is halved in spore mother cells, but recovers before, or immediately after, spore germination. In the ngeneration, plastids multiplied by binary fission, with DNA duplication, and the plastid DNA content was maintained at the same level as that of the 2n-generation.It is known that only the maternal organelle DNA are transmitted to offspring via the maternal inheritance system in many eukaryotes. Previously, we reported that plastids in the spore mother cells of Anthoceros punctatus duplicated their own DNA before plastidkinesis (reviewed in Kuroiwa 1989Kuroiwa , 1991 of the first plastid division, but did not replicate their own DNA during the second plastid division. In addition, the DNA content of plastids which had completed their division was halved as well as the DNA content of cell nuclei (Izumi and Ono 1994). In A. punctatus, if only maternal plastid DNA are transmitted to offspring by maternal inheritance, it would mean that the plastid DNA content in the fertilized egg must be about equal to that of the haploid plant. Furthermore, if DNA replication cycles of plastid DNA correspond to those of cell nucleus DNA during the life cycle of this species, plastid DNA content should halved every generation.However, it has been reported that the replication cycle of mitocondrial DNA changes during the life cycle of. Physarum polycephalum (Kawano et al. 1983, Kawano 1991. Kuroiwa et al. (1981b) have reported that the DNA content of plastids increases remarkably during germination in higher plants. In A. punctatus, if only the maternal plastid DNA are transmitted to the offspring by maternal inheritance, there is a possibility that the plastid DNA content of this species is recovered at a certain point during the life cycle.In this paper, we describe relative changes in the plastid DNA content during the life cycle of A. punctatus. Center.

show abstract

“…Physarum polycephalum (Kawano et al 1983, Kawano 1991. Kuroiwa et al (1981b) have reported that the DNA content of plastids increases remarkably during germination in higher plants.…”

Section: Discussionmentioning

confidence: 99%

Changes in Plastid DNA Content during the Life Cycle of the Hornwort Anthoceros punctatus L.

Izumil

Ono

1999

CYTOLOGIA

View full text Add to dashboard Cite

show abstract

“…However, the thin region which is going to become the site of division may move along the mitochondrion several times and sequences of fission and fusion events a t the same site are very common sec], 6b). Thus, the dumbbell shape observed in several large mitochondria (e.g., Baranowski et al, 1991;Kawano, 1991;Kuroiwa, 1982) seems to be a form changing relatively slowly, while more slender mitochondria do not divide into almost symmetric parts.…”

Section: Observations With Phase Contrast Microscopymentioning

confidence: 96%

Dynamics of mitochondria in living cells: Shape changes, dislocations, fusion, and fission of mitochondria

Bereiter‐Hahn

Vöth

1994

Microscopy Res & Technique

782

496

View full text Add to dashboard Cite

Mitochondria are semi-autonomous organelles which are endowed with the ability to change their shape (e.g., by elongation, shortening, branching, buckling, swelling) and their location inside a living cell. In addition they may fuse or divide. These dynamics are discussed. Dislocation of mitochondria may result from their interaction with elements of the cytoskeleton, with microtubules in particular, and from processes intrinsic to the mitochondria themselves. Morphological criteria and differences in the fate of some mitochondria argue for the presence of more than one mitochondrial population in some animal cells. Whether these reflect genetic differences remains obscure. Emphasis is laid on the methods for visualizing mitochondria in cells and following their behaviour. Fluorescence methods provide unique possibilities because of their high resolving power and because some of the mitochondria-specific fluorochromes can be used to reveal the membrane potential. Fusion and fission often occur in short time intervals within the same group of mitochondria. At sites of fusion of two mitochondria material of the inner membrane, the matrix compartment seems to accumulate. The original arrangement of the fusion partners is maintained for some minutes. Fission is a dynamic event which, like fusion, in most cases observed in vertebrate cell cultures is not a straight forward process but rather requires several "trials" until the division finally occurs. Regarding fusion and fission hitherto unpublished phase contrast micrographs, and electron micrographs have been included.

show abstract

“…polycephalum by both light and electron microscopy, since the mitochondria contain electron-dense rod-shaped mt-nuclei (Kuroiwa, 1973(Kuroiwa, , 1974(Kuroiwa, , 1982. Figure 1 schematically summarizes the results of DAFT epifluorescence microscopy and electron microscopy of the behavior of mitochondria throughout the life cycle (Kawano, 1991).…”

Section: Behavior Of Mitochondria and Their Nuclei Throughout The Lifmentioning

confidence: 99%

“…However, mitochondrial fusion occurs after mating Mif + and Mif-amoebae (c,n. (Reproduced from Kawano, 1991, with permission of the publisher.) DNAs in S. cereuisiae are also organized with several proteins of MW 67 kDa, 52 kDa, 38 kDa, 32 kDa, 30 kDa, 29 kDa, and 20 kDa to form mt-nuclei (Miyakawa et al, 1984).…”

Section: Introductionmentioning

confidence: 99%

“…In general, mitochondriokinesis occurs by contraction rather than by partition of the inner membrane. Physarum polycephalum o 1994 Wiley-Liss, Inc. (Kuroiwa et al, 1992) and NicotiaLa tabacum, the slime mold P. polycephalum (Kawano, 1991), and the yeasts Saccharomyces cerevisiae (Miyakawa et al, 1984) and Candida albicans can also be followed during the cell division cycle and life cycle. Intact mt-nuclei have been isolated from the mitochondria of P. polycephalum and the yeast Saccharomyces cereuisiae.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Molecular and cellular mechanisms of mitochondrial nuclear division and mitochondriokinesis

Kuroiwa

Ohta

Kuroiwa

et al. 1994

Microscopy Res & Technique

View full text Add to dashboard Cite

Our present understanding of mitochondrial division can be summarized as follows: Mitochondria contain a specific genome, synthesize their own DNA, and multiply semi-autonomously. Strands of mitochondrial DNA (mt-DNA) in the in vivo organelles of all eukaryotes are organized to form mitochondrial nuclei (nucleoids) (mt-nuclei) with specific proteins including a histone-like protein and transcription factors at the central region of the mitochondrion. We can easily observe the mt-nucleus in vivo mitochondria in various organisms such as fungi, algae, plants, and animals by using high-resolution epifluorescence microscopy. Therefore, the process of mitochondrial division can be clearly separated into two main events: division of the mt-nuclei and mitochondriokinesis analogous to cytokinesis. Mitochondria undergo binary division which is accompanied by the division of the mt-nucleus. A remarkable characteristic of mitochondrial multiplication during the mitochondrial life cycle is that mitochondria can multiply the mt-chromosome by endoduplication until 50-100 copies are present. Mitochondria can then divide without mitochondrial DNA synthesis to eventually contain 1-5 copies of the mt-chromosome. This characteristic phenomenon can be observed during cell differentiation, such as during the formation of plasmodia and sclerotia of Physarum polycephalum and during embryogenesis and the formation of meristematic tissues in plants. The mitochondrial chromosome has a mitochondrial "kinetochore (centromere)" which is A-T rich and contains specific sequences such as topoisomerase binding sites, tandem repeats, and inverted repeats. A bridge of proteins may exist between the kinetochore DNA and membrane systems. Mitochondrial chromosomes can divide according to the growth of a membrane system between the kinetochores. Mitochondriokinesis progresses steadily along with mitochondrial nuclear division. As the membrane at the equatorial region of a mitochondrion contracts, the neck of the cleavage furrow narrows, and eventually the daughter mitochondria are separated. An actin-like protein may power mitochondriokinesis by separating the daughter mitochondria. In general, mitochondriokinesis occurs by contraction rather than by partition of the inner membrane.

show abstract

The life cycle of mitochondria in the true slime mould,Physarum polycephalum

Cited by 16 publications

References 50 publications

Changes in Plastid DNA Content during the Life Cycle of the Hornwort Anthoceros punctatus L.

Changes in Plastid DNA Content during the Life Cycle of the Hornwort Anthoceros punctatus L.

Dynamics of mitochondria in living cells: Shape changes, dislocations, fusion, and fission of mitochondria

Molecular and cellular mechanisms of mitochondrial nuclear division and mitochondriokinesis

Contact Info

Product

Resources

About