Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae)

The fine structure of spermatozoon of the dilepidid cestode Dilepis undula is described. The main structural elements of the sperm cell are: 1) plasma membrane and underlying single row of cortical microtubules; 2) a single axoneme of the unique platyhelminth 9+˝1˝ type; 3) periaxonemal sheath compo...

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Hauptverfasser: Swiderski, Z., Salamatin, R.V., Tkach, V.V.
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Zitieren:Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae) / Z. Swiderski, R.V. Salamatin, V.V. Tkach // Вестник зоологии. — 2000. — Т. 34, № 4-5. — С. 93-97. — Бібліогр.: 12 назв. — англ.

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Digital Library of Periodicals of National Academy of Sciences of Ukraine
id nasplib_isofts_kiev_ua-123456789-64496
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spelling Swiderski, Z.
Salamatin, R.V.
Tkach, V.V.
2014-06-15T18:42:48Z
2014-06-15T18:42:48Z
2000
Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae) / Z. Swiderski, R.V. Salamatin, V.V. Tkach // Вестник зоологии. — 2000. — Т. 34, № 4-5. — С. 93-97. — Бібліогр.: 12 назв. — англ.
0084-5604
https://nasplib.isofts.kiev.ua/handle/123456789/64496
595.121
The fine structure of spermatozoon of the dilepidid cestode Dilepis undula is described. The main structural elements of the sperm cell are: 1) plasma membrane and underlying single row of cortical microtubules; 2) a single axoneme of the unique platyhelminth 9+˝1˝ type; 3) periaxonemal sheath composed of the crystalline-like material; 4) elongated electron-dense nucleus; 5) crested body. The similarities and differences between the ultrastructure of spermatozoa of D. undula and that of some other cestodes, are briefly discussed.
Описано тонкое строение сперматозоидов Dilepis undula. Основными структурными элементами сперматозоида являются: 1) плазматическая мембрана с подлежащим одним рядом кортикальных микротрубочек; 2) единственная аксонема, устроенная по типу 9+1, уникальному для плоских червей; 3) цилиндрический периаксонемальный футляр, образованный из кристаллоподобного материала; 4) удлиненное электронно-плотное ядро и 5) гребневидное тело. Кратко обсуждены сходства и различия в структуре сперматозоидов у D. undula и некоторых других цестод
The authors wish to thank Dr Yuri Kuzmin (Institute of Zoology NANU, Kyiv) for his technical assistance. The research was carried out in the framework of the scientific co-operation between the Institute of Zoology of the Ukrainian National Academy of Sciences and the Institute of Parasitology of the Polish Academy of Sciences. This study was financially supported by the grant ¹ 6 PO4Ñ 01314 from the Polish Committee for Scientific Research (KBN) and by a fellowship from the J. Mianowski Foundation (Warsaw, Poland) to R. Salamatin.
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Інститут зоології ім. І.І. Шмальгаузена НАН України
Вестник зоологии
Краткие сообщения
Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae)
Электронно-микроскопическое исследование сперматозоидов цестоды Dilepis undula (Cyclophyllidea, Dilepididae)
Article
published earlier
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
collection DSpace DC
title Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae)
spellingShingle Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae)
Swiderski, Z.
Salamatin, R.V.
Tkach, V.V.
Краткие сообщения
title_short Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae)
title_full Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae)
title_fullStr Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae)
title_full_unstemmed Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae)
title_sort electron microscopical study of spermatozoa of the cestode dilepis undula (cyclophyllidea, dilepididae)
author Swiderski, Z.
Salamatin, R.V.
Tkach, V.V.
author_facet Swiderski, Z.
Salamatin, R.V.
Tkach, V.V.
topic Краткие сообщения
topic_facet Краткие сообщения
publishDate 2000
language English
container_title Вестник зоологии
publisher Інститут зоології ім. І.І. Шмальгаузена НАН України
format Article
title_alt Электронно-микроскопическое исследование сперматозоидов цестоды Dilepis undula (Cyclophyllidea, Dilepididae)
description The fine structure of spermatozoon of the dilepidid cestode Dilepis undula is described. The main structural elements of the sperm cell are: 1) plasma membrane and underlying single row of cortical microtubules; 2) a single axoneme of the unique platyhelminth 9+˝1˝ type; 3) periaxonemal sheath composed of the crystalline-like material; 4) elongated electron-dense nucleus; 5) crested body. The similarities and differences between the ultrastructure of spermatozoa of D. undula and that of some other cestodes, are briefly discussed. Описано тонкое строение сперматозоидов Dilepis undula. Основными структурными элементами сперматозоида являются: 1) плазматическая мембрана с подлежащим одним рядом кортикальных микротрубочек; 2) единственная аксонема, устроенная по типу 9+1, уникальному для плоских червей; 3) цилиндрический периаксонемальный футляр, образованный из кристаллоподобного материала; 4) удлиненное электронно-плотное ядро и 5) гребневидное тело. Кратко обсуждены сходства и различия в структуре сперматозоидов у D. undula и некоторых других цестод
issn 0084-5604
url https://nasplib.isofts.kiev.ua/handle/123456789/64496
citation_txt Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae) / Z. Swiderski, R.V. Salamatin, V.V. Tkach // Вестник зоологии. — 2000. — Т. 34, № 4-5. — С. 93-97. — Бібліогр.: 12 назв. — англ.
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fulltext Vestnik zoologii, 34(4—5): 93—97, 2000 © 2000 Z. Swiderski, R. V. Salamatin, V. V. Tkach UDC 595.121 ELECTRON MICROSCOPICAL STUDY OF SPERMATOZOA OF THE CESTODE DILEPIS UNDULA (CYCLOPHYLLIDEA, DILEPIDIDAE) Z. Swiderski1, R. V. Salamatin2, V. V. Tkach2 1W. Stefański Institute of Parasitology, Polish Academy of Sciences, 51/55 Twarda st., 00-818 Warsaw, Poland 2I. I. Schmalhausen Institute of Zoology, vul. B. Khmelnits’kogo, 15, Kyiv-30, MSP, 01601 Ukraine Accepted 25 January 2000 Electron Microscopical Study of Spermatozoa of the Cestode Dilepis undula (Cyclophyllidea, Dilepididae). Swid- erski Z., Salamatin R. V., Tkach V. V. – The fine structure of spermatozoon of the dilepidid cestode Dilepis undula is described. The main structural elements of the sperm cell are: 1) plasma membrane and underlying single row of cortical microtubules; 2) a single axoneme of the unique platyhelminth 9+˝1˝ type; 3) periaxonemal sheath composed of the crystalline-like material; 4) elongated electron-dense nucleus; 5) crested body. The similarities and differences between the ultrastructure of spermatozoa of D. undula and that of some other cestodes, are briefly discussed. Key wo rd s : spermatozoa, ultrastructure, Cestoda, Dilepididae, Dilepis undula. Ýëåêòðîííî-ìèêðîñêîïè÷åñêîå èññëåäîâàíèå ñïåðìàòîçîèäîâ öåñòîäû Dilepis undula (Cyclophyllidea, Dilepididae). Ñâèäåðñêèé Ç., Ñàëàìàòèí Ð. Â., Òêà÷ Â. Â. – Îïèñàíî òîíêîå ñòðîåíèå ñïåðìàòîçîèäîâ Dilepis undula. Îñíîâíûìè ñòðóêòóðíûìè ýëåìåíòàìè ñïåðìàòîçîèäà ÿâëÿþòñÿ: 1) ïëàçìàòè÷åñêàÿ ìåìáðàíà ñ ïîäëåæàùèì îäíèì ðÿäîì êîðòèêàëüíûõ ìèêðîòðóáî÷åê; 2) åäèíñòâåííàÿ àêñîíåìà, óñò- ðîåííàÿ ïî òèïó 9+˝1˝, óíèêàëüíîìó äëÿ ïëîñêèõ ÷åðâåé; 3) öèëèíäðè÷åñêèé ïåðèàêñîíåìàëüíûé “ôóòëÿð”, îáðàçîâàííûé èç êðèñòàëëîïîäîáíîãî ìàòåðèàëà; 4) óäëèíåííîå ýëåêòðîííî-ïëîòíîå ÿäðî è 5) ãðåáíåâèäíîå òåëî. Êðàòêî îáñóæäåíû ñõîäñòâà è ðàçëè÷èÿ â ñòðóêòóðå ñïåðìàòîçîèäîâ ó D. undula è íåêîòîðûõ äðóãèõ öåñòîä. Êëþ÷åâûå ñëîâà : ñïåðìàòîçîèäû, óëüòðàñòðóêòóðà, Cestoda, Dilepididae, Dilepis undula. Inroduction Ultrastructural characteristics of spermatozoa provide important criteria for the systematics and analysis of the phylogenetic relationships among cestodes (Swiderski, 1968, 1970; Euzet et al., 1981; Justine, 1991, 1995, 1998; Bâ, Marchand, 1995). Up to now, data on the spermatozoa ultrastructure of about 70 cestode species belonging to all 12 recognised orders of Eucestoda, are available in the literature (see Justine, 1991, 1998; Bâ, Marchand, 1995). For more detailed analysis, however, spermatozoa of more cestode taxa should be studied. According to our knowledge, ultrastructure of spermatozoa of only one dilepidid species, Molluscotaenia crassiscolex, has been examined so far (Swiderski, Tkach, 1996). Miquel and Marchand (1997) in their paper on the spermatozoa of Dipylidium caninum noted that it was the first study on the representative of Dilepididae. However, in their later paper (Miquel, Marchand, 1998) the authors corrected this systematic allocation of D. caninum which, according to the widely accepted classification (Jones, 1994), belongs to the family Dipylidiidae. The aim of the present study is to describe the fine structure of spermatozoon of the cestode Dilepis undula which is a characteristic representative of the family Dilepididae and a type species of the genus Dilepis. Material and methods Adult specimens of Dilepis undula (Schrank, 1788), containing mature and pregravid proglottids, were removed from the intestine of a fieldfare (Turdus pilaris), from the vicinity of Kyiv, Ukraine. The proglottids were quickly rinsed in saline, cut into small pieces and fixed in 4% glutaraldehyde in sodium cacodylate buffer (pH 7.4). After washing in the same buffer and postfixation for 2 h in 1% OsO4, they were dehydrated in an ethanol series, infil- trated with propylene oxide and embedded in Spurr's resin. Ultrathin sections, mounted on uncoated copper grids, double stained with lead citrate and uranyl acetate, were examined under a JEM-1200EX electron microscope oper- ated at an accelerateing voltage of 80 kV. Z. Swiderski, R. V. Salamatin, V. V. Tkach 94 Results Mature spermatozoa of D. undula are strongly elongated, filiform cells, tapered at both extremities and lacking mitochondria. They measure about 300—350 μm in length and their maximum diameter, in the nucleus containing region, is 0,5—0,6 μm. Fig. 1. Diagram and corresponding reconstruction of the spermatozoon of D. undula from the representative cross- sections of consecutive regions along longitudinal axis of sperm body. Abbreviations to all figures: Ax – axoneme; c – core; Cb – crested body; cm – central matrix; CU – central core unit of the axoneme; cx – cortex; DA – dynein arms; DPT – double peripheral tubules; M – plasma membrane; Mt – microtubules; N – nucleus; P – periaxonemal sheath; s – spokes; sf A – subfiber A or tubule A; sf B – subfi- ber B or tubule B. Ðèñ. 1. Äèàãðàììà è ñîîòâåòñòâóþùàÿ ðåêîíñòðóêöèÿ ñïåðìàòîçîèäà D. undula, ñîñòàâëåííàÿ èç ïîïåðå÷íûõ ñðåçîâ ó÷àñòêîâ, ïîñëåäîâàòåëüíî ðàñïîëîæåííûõ âäîëü ïðîäîëüíîé îñè ñïåðìàòîçîèäà. Ñîêðàùåíèÿ êî âñåì èëëþñòðàöèÿì: Ax – àêñîíåìà; c – öåíòðàëüíûé ýëåêòðîííî-ïëîòíûé öèëèíäð ñåðäöå- âèííîé ÷àñòè àêñîíåìû; Cb – ãðåáíåâèäíîå òåëî; cm – öåíòðàëüíûé ìàòðèêñ; CU – ñåðäöåâèííàÿ ÷àñòü àêñîíåìû; cx – êîðòåêñ; DA – äèíåèíîâûå âûðîñòû; DPT – äâîéíûå ïåðèôåðè÷åñêèå ìèêðîòðóáî÷êè (äóá- ëåòû); M – ïëàçìàòè÷åñêàÿ ìåìáðàíà; Mt – êîðòèêàëüíûå ìèêðîòðóáî÷êè; N – ÿäðî; P – öèëèíäðè÷åñêèé ïåðèàêñîíåìàëüíûé “ôóòëÿð”; s – “ñïèöû”; ñîåäèíÿþùèå ïåðèôåðè÷åñêèå äóáëåòû ñ ñåðäöåâèííîé ÷àñòüþ àêñîíåìû; sf A – ìèêðîòðóáî÷êà “À” â äóáëåòå; sf B – ìèêðîòðóáî÷êà “Â” â äóáëåòå. Study of Spermatozoa of the Cestode Dilepis undula… 95 Main structural components of the sperm cell are: (1) plasma membrane and underlying single row of cortical microtubules; (2) a single axoneme of the unique platyhelminth 9+˝1˝ type; (3) periaxonemal sheath composed of the crystalline-like material; (4) elongated elec- tron-dense nucleus; (5) crested body (Mokhtar-Maamouri, Swiderski, 1975). Smooth plasma membrane is of uniform thickness. Cortical microtubules, situated under the plasma membrane (figs 2, 6, 7) are spiralled at variable angle (between 35—45°) to the spermatozoon axis. The axoneme is 0.15—0.18 μm in diameter (figs 6, 7). It contains a central core unit (0.05—0.06 μm) and nine peripheral doublets of microtubules (figs 1, 2, 6). The central core unit consists of an electron-dense core and two cylindrical areas around it composed of: (a) an electron-lucent matrix, and (b) an electron-dense cortex. The peripheral doublet unit of axoneme is composed of: (1) subfiber A or tubule A connected by spoke with the central region through an electron-dense region which partially occlude the lumen of the tubule A; (2) two dyneine arms attached to tubule A; and (3) subfiber B or tubule B (figs 1, 2, 6). The spokes connecting the peripheral doublets with the central region, sometimes appear on the cross-section with different prominence, which confirms their helical arrangement around the central core unit. The periaxonemal sheath has striated appearance on the sections. It is composed of crystalline-like material and consists of moderately electron-dense radial rods separated by electron-lucent spaces of the same thickness (figs 3—6). Numerous granules of moderately electron-dense material occur in the middle and posterior regions of the sper- matozoa. An electron-dense elongated nucleus forming a loose spiral around the axoneme (figs 1, 3, 5), is changing its shape and thickness, when observed on cross-sections at different levels. It begins as a cylindrical structure, initially round on cross-sections, and progressively flattens towards the posterior end, becoming crescent-shaped on the cross-sections (fig. 2). The pe- riodicity of the nuclear spiral varies along the nucleus length. The nucleus occupies relatively short part of the spermatozoon length. Externally, the spermatozoon shows near its anterior end a single, short, helical crested body, associated with cortical microtubules. Cross-sections through the spermatozoon, near its anterior and posterior tips, are much smaller in diameter and contain only the axoneme surrounded by the plasma membrane (fig. 1). Fig. 2. A three-dimentional diagram of the nucleus containing part of the spermatozoon. Note a complex structure of the 9+”1” axoneme of platyhelmynth type. Ðèñ. 2. Òðåõìåðíàÿ äèàãðàììà ÿäðîñîäåðæàùåãî ó÷àñòêà ñïåðìàòîçîèäà. Âàæíî îòìåòèòü ñëîæíóþ ñòðóêòóðó àêñîíåìû, óñòðîåííîé ïî òèïó 9+”1”, õàðàêòåðíîìó äëÿ ïëîñêèõ ÷åðâåé. Z. Swiderski, R. V. Salamatin, V. V. Tkach 96 Discussion An apical cone and a posterior electron-dense material, described in spermatozoa of some other cyclophyllidean cestodes (Justine, 1998; Miquel, Marchand, 1998), were not ob- served in two dilepidids examined so far (Swiderski, Tkach, 1996; present study); in both cases the fully mature spermatozoa stored in the seminal receptacle, were studied. In D. undula, only one crested body was observed, while 1 to 6 crest-like bodies were reported in other cestodes (for references see Miquel, Marchand, 1997, 1998). The main Figs 3—7. Details of supermatozoal ultrastructure. Figs 3—5: oblique sections through the nuclear part showing arrange- ment of microtubiules at different angles to the axoneme, spiral pattern of nucleus and periaxonemal sheath composed of the crystalline-like material. Figs 6—7: cross-sections through the anuclear parts. Note: a single row of cortical micro- tubules and striated appearance of the periaxonemal sheath. Ðèñ. 3—7. Äåòàëè óëüòðàñòðóêòóðû ñïåðìàòîçîèäà. Ðèñ. 3—5: ñðåçû ÷åðåç ÿäðîñîäåðæàùóþ ÷àñòü, äåìîíñòðè- ðóþùèå ðàñïîëîæåíèå ìèêðîòðóáî÷åê ïîä ðàçëè÷íûì óãëîì ê àêñîíåìå, ñïèðàëüíóþ ôîðìó ÿäðà, à òàêæå ïåðèàêñîíåìàëüíûé “ôóòëÿð”, ñîñòîÿùèé èç êðèñòàëëîïîäîáíîãî âåùåñòâà. Ðèñ. 6—7: ïîïåðå÷íûå ñðåçû ÷åðåç áåçúÿäåðíóþ ÷àñòü. Âàæíî îòìåòèòü íàëè÷èå îäíîãî ðÿäà êîðòèêàëüíûõ ìèêðîòðóáî÷åê è èñ÷åð÷åííîñòü ïåðè- àêñîíåìàëüíîãî “ôóòëÿðà”. Study of Spermatozoa of the Cestode Dilepis undula… 97 difference between two dilepidids, examined so far, is the presence of the periaxonemal sheath in D. undula (present study) and its absence in Molluscotaenia crassiscolex (Swiderski, Tkach, 1996). The fine structure of the spermatozoon of D. undula is similar to that described in other cyclophyllideans (Swiderski, 1970; Euzet et al., 1981; Justine, 1991, 1995, 1998; Bâ, Mar- chand, 1995) and is characterised by the presence of a single axoneme. This type of the spermatozoon organisation is observed in the evolutionary more advanced groups of cesto- des. It represents probably a result of the secondary reduction in the number of axonemes from the ancestral 2-axoneme type which is observed in more primitive Pseudophyllidea, Tetrarhynchidea and Proteocephalidea (Euzet et al., 1981). Acknowledgements The authors wish to thank Dr Yuri Kuzmin (Institute of Zoology NANU, Kyiv) for his technical assistance. The research was carried out in the framework of the scientific co-operation between the Institute of Zoology of the Ukrainian National Academy of Sciences and the Institute of Parasitology of the Polish Academy of Sciences. This study was financially supported by the grant ¹ 6 PO4Ñ 01314 from the Polish Committee for Scientific Research (KBN) and by a fellowship from the J. Mianowski Foundation (Warsaw, Poland) to R. Salamatin. Bâ C. T., Marchand B. Spermiogenesis, spermatozoa and phyletic affinities in the Cestoda // Mémoires du Muséum national d’Histoire naturelle. – 1995. – 166: Advances in spermatozoal phylogeny and taxonomy / Eds. B. G. M. Jamieson, J. Ausio, J.-L. Justine. – P. 87—95. Euzet L., Swiderski Z., Mokhtar-Maamouri F. Ultrastructure comparée du spermatozoïde des Cestodes. Relations avec la phylogenèse // Ann. Parasitol. – 1981. – 58. – P. 247—259. Jones A. Family Dipylidiidae // Keys to the Cestode parasites of Vertebrates / Eds. L. K. Khalil, A. Jones. – Cam- bridge : University Press, 1994. – P. 555—558. Justine J.-L. Phylogeny of parasitic Platyhelminthes: a critical study of synapomorphies proposed on the basis of the ultrastructure of spermiogenesis and spermatozoa // Canadian J. Zool. – 1991. – 69. – P. 1421—1440. Justine J.-L. Spermatozoal ultrastructure and phylogeny in the parasitic Platyhelminthes // Mémoires du Muséum national d’Histoire naturelle.– 1995. – 166: Advances in spermatozoal phylogeny and taxonomy. / Eds. B. G. M. Jamieson, J. Ausio, J.-L. Justine. – P. 55—86. Justine J.-L. Spermatozoa as phylogenetic characters for the Eucestoda // J. Parasitol. – 1998. – 84. – P. 385— 408. Miquel J., Marchand B. Ultrastructure of the spermatozoon of Dipylidium caninum (Cestoda, Cyclophyllidea, Dilepididae), an intestinal parasite of Canis familiaris // Parasitol. Research. – 1997. – 83. – P. 349—355. Miquel J., Marchand B. Ultrastructure of spermiogenesis and the spermatozoon of Anoplocephaloides dentata (Cestoda, Cyclophyllidea, Anoplocephalidae), an intestinal parasite of Arvicolidae rodents // J. Parasitol. – 1998. – 84. – P. 1128—1136. Mokhtar-Maamouri F., Swiderski Z. Étude en microscopie électronique de la spermatogénèse de deux cestodes Acan- thobothrium filicolle benedenii Loennberg, 1889 et Oncobothrium uncinatum (Rud., 1819) (Tetraphyllidea, Onchobothriidae) // Zeitschr. Parasitenk. – 1975. – 47. – P. 269—281. Swiderski Z. The fine structure of the spermatozoon of sheep tapeworm, Moniezia expansa (Rud., 1810) (Cyclophyl- lidea, Anoplocephalidae) // Zoologica Poloniae. – 1968. – 18. – P. 47—486. Swiderski Z. An electron microscope study of spermatogenesis in cyclophyllidean cestodes with emphasis on the comparison of fine structure of mature spermatozoa // J. Parasitol. – 1970. – 56. – P. 337—338. Swiderski Z., Tkach V. V. Ultrastructure of mature spermatozoon in dilepidid cestode Molluscotaenia crassiscolex (Linstow, 1890) // Parassitologia. – 1996. – 38. – P. 97.