Summary
Changes in the morphology and quantity of mitochondria and mitochondrial DNA during eupyrene and apyrene spermatogenesis in the silkworm were examined by electron microscopy and by fluorescence in situ hybridization with a 2 kb silkworm mitochondrial DNA clone (pBmMtE2). In the eupyrene spermatogenesis, the spermatocytes at early prophase I contained only a small amount of cytoplasm and showed a rather faint signal. As the cells grew larger in the later prophase I, the signal grew stronger. In the eupyrene spermatids, an especially strong signal was evident in the nebenkerns, in which all the cell's mitochondria were aggregated, and the strong fluorescence was maintained in mitochondrial derivatives. On the other hand, the apyrene cells were markedly smaller throughout spermatogenesis, showing much fainter signals for mitochondrial DNA than the eupyrene. Electron microscopy disclosed considerable differences in the behavior of mitochondria between the apýrene and the eupyrene cells. The observed qualitative and/or quantitative differences in the mitochondria may have some physiological bearing on the spermatogenesis of the two types of sperm.
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Abbreviations
- FISH:
-
fluorescence in situ hybridization
- FITC:
-
fluorescein isothiocyanate
- kb:
-
kilo base pair
- PI:
-
propidium iodide
- PBS:
-
phosphate-buffered saline
References
Fugo H, Yamauchi M, Dedos SG (1996) Testicular ecdysteroids in the silkmoth,Bombyx mori. Proc Jap Acad 72: 34–37
Holm PB, Rasmussen SW (1980) Chromosome pairing, recombination and chiasma formation in diploidBombyx males. Carlsberg Res Commun 45: 483–548
Katsuno S (1977) Studies on eupyrene and apyrene spermatozoa in the silkworm,Bombyx mori L. (Lepidoptera: Bombycidae) I: the intratesticular behavior of the spermatozoa at various stages from the 5th instar to the adult. Appl Entomol Zool 12: 142–153
— (1978) Studies on eupyrene and apyrene spermatozoa in the silkworm,Bombyx mori L. (Lepidoptera: Bombycidae) VII: the motility of sperm bundles and spermatozoa in the reproductive organs of males and females. Appl Entomol Zool 13: 91–96
Kawamura N (1978) The early embryonic mitosis in normal and cooled eggs of the silkworm,Bombyx mori. J Morphol 158: 57–72
Leviatan R, Friedländer M (1979) The eupyrene-apyrene dichotomous spermatogenesis of Lepidoptera I: the relationship with postembryonic development and the role of the decline in juvenile hormone titer toward pupation. Dev Biol 68: 515–524
Machida J (1929) Eine experimentelle Untersuchung über die apyrene Spermatozoen des Seidenspinners,Bombyx mori. Z Zellforsch Mikrosk Anat 9: 466–510
Osanai M, Kasuga H, Aigaki T (1989) Induction of motility of apyrene spermatozoa and dissociation of eupyrene sperm bundles of the silkmoth,Bombyx mori, by Initiatorin and trypsin. Invertebr Reprod Dev 15: 97–103
Petit JM, Ratinaud MH, Cordelli E, Spano M, Julien R (1995) Mouse testis cell sorting according to DNA and mitochondrial changes during spermatogenesis. Cytometry 19: 304–312
Rasmussen SW (1976) The meiotic prophase inBombyx mori females analyzed by three dimensional reconstruction of synaptonemal complexes. Chromosoma 54: 245–293
— (1977) The transformation of the synaptonemal complex into the “elimination chromatin” inBombyx mori oocytes. Chromosoma 60: 205–221
Silberglied RE, Sheperd JG, Dickinson JL (1984) Ennuch: the role of apyrene sperm in Lepidoptera? Am Nat 123: 255–265
Tazima Y (1967) The genetics of the silkworm. Logos Press, London
Yamashiki N, Kawamura N (1997) Behaviors of nucleus, basal bodies and microtubules during eupyrene and apyrene spermiogenesis in the silkworm,Bombyx mori (Lepidoptera). Dev Growth Differ 39: 715–722
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Kawamura, N., Yamashiki, N. & Bando, H. Behavior of mitochondria during eupyrene and apyrene spermatogenesis in the silkworm,Bombyx mori (Lepidoptera), investigated by fluorescence in situ hybridization and electron microscopy. Protoplasma 202, 223–231 (1998). https://doi.org/10.1007/BF01282550
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DOI: https://doi.org/10.1007/BF01282550