Summary
We present strong electron microscopic evidence that the mitochondrial-dividing ring (MD-ring) forms as a closed ring about 50 nm wide and 10 nm thick, at the contact point where the micro-body attaches to the mitochondrion. This ring forms in the cytoplasm around an equatorial plane perpendicular to the major axis of a mitochondrion. As the MD-ring increases in both width and thickness, the mitochondrion becomes dumbbell-shaped with a narrow interconnecting isthmus. Then, by successive contractions of the ring, the dumbbell-shaped mitochondrion separates to generate two daughter mitochondria. We also observed formation of an electron dense plastid-dividing ring (PD-ring) during plastid divisions. We noted too the behaviour of the MB in relation to the contraction of MD-rings and PD-rings.
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Abbreviations
- DAPI:
-
4′,6-diamidino-2-phenylindole
- mt-nucleus:
-
mitochondrial nucleus
- pt-nucleus:
-
plastid nucleus
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Kuroiwa, T., Suzuki, K., Itou, R. et al. Mitochondria-dividing ring: ultrastructual basis for the mechanism of mitochondrial division inCyanidioschyzon merolae . Protoplasma 186, 12–23 (1995). https://doi.org/10.1007/BF01276930
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DOI: https://doi.org/10.1007/BF01276930