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Presence of abnormal cilia in the mucosa of the male gonoduct of Bolinus (Murex) brandaris (Gastropoda, Prosobranchia, Muricidae) PDF

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Alderete de Majo etal.: Espermatogénesis en Sarasinula linguaeformis postulado de Franzen (1956) sustenta gía de la fecundación, acorde a la posi- queexiste una relaciónentre la morfolo- ción primitiva de los Veronicellidae gía del espermatozoide y la biología de dentro del contexto de los Euthyneura. la fecundación, y que la forma de las Esto último se fundamentaría porqueen células está influenciada no sólo por las los Opisthobranchia y Pulmonata, la relaciones filogenéticas, sino también forma de los espermatozoides se modi- por los requerimientos del espermato- fica y no se encontraron indicios de la zoide en el proceso de fecundación- condición primitiva en ninguno de los (Afzelius, 1979). casosestudiados (Franzen, 1955). De lo expuesto cabe inferir que el espermatozoide de Sarasinula linguaefor- mis ostentaría un modelo de tipo primi- AGRADECIMIENTOS tivo, a pesar que su modo de fecunda- ciónse realiza através de órganos copu- Los autores agradecen al Dr. J. W. ladores. Estehechopodría indicarquela Thomé la identificación de la especie morfología del espermatozoide aquí estudiada y al Ing. Pablo Brainovich su descrito, estaría vinculado más bien con colaboración en la transcripción con las relaciones filéticas que con la biolo- procesadordetextosencomputadora. bibliografía Afzelius,B.A., 1979.Spermstructureinre- Chatton, E. yTuzet, O., 1942. Production lationto Phylogenyin lowermetazoa. En parcertains individus de Lombriciens de Fawcett, D. W. y Bedford, J. M. (Eds.): spermatides normales et de spermatides The Spermatozoon: Mataration, MotiUty, nucléolées enpartiénumerique.Annales Swface Properties and Comparative As- de la Société RoyaleZoologique de Belgi- peéis. UrbanySchwarzenberg,Baltimore, que, 214: 894- 896. Munich, xvi + 441 pp. Chatton, E. yTuzet, O., 1943. Sur la for- AlderetedeMajo,A. M., 1988.Estudiosci- mationdegoniespolyvalentesetdesper- tológicosenoligoquetosterrícolasdelapro- mies géantes chez deux Lumbriciens. vincia de Tucumán. 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(London) Ltd., vi+ 462 pp. nada, ovogenesi e spermatogenesi in Va- JOOSSE,J., BOER, M. H.YCORNELISSE, C.J., ginulusborellianus(Colosi)einLaevícau- 1968. Gametogenesis and ovoposition in lis alte (Ferussac). Monítore Zoológico Lymnaea stagnalis as influenced by Italiano, 73, n. 1/3: 3-60, 1-30 est. gamma Irradiation and huger. Symposia Sabelli, B.,SabelliScanabissi,F.yMerloni, qf the Zoological Society qfLondon, 22: M., 1978. Distribution on Germ Cells in 213- 235. the Gonadic Acina ofDeroceras reticula- Lucas, A., 1971. Les Gametes des MoIIus- tum(MüIIer)(Gastropoda, Pulmonata,Sty- ques. Haliotis, 1 (2): 185-214. lommatophora).MonítoreZoológicoItaliano Martinucci,G. B.yFelluga, B., 1975.Early (n. s.), 12: 95-106. development of the cytophorus in pre- Thomé, J. W., 1975. Os géneros da familia meioticmalegonialcellsoíEiseniafoettda Veronicellidae ñas Américas (Mollusca, (Sav.).BolletttnodiZoología,42: 271-273. Gastropoda).IheringiaserieZoología(Bra- Martinucci, G. B., Felluga, B. y Carli, S., zíl), 48: 3-56. 1977.Developmentanddegenerationofcy- TuzET, O., 1940. Sur la spermiogénése de tophorusdurlngspermiohistogenesisin£i- VOncidiella céltica Cuvier et la place des seniafoetida(Sav.). BoüettinodiZoología, Oncidiidadanslaclassification.Archivede 44: 383- 398. Zoologíe Experiméntale et Genérale, 81 Quattrini, D. yLanza, B., 1964a. Lesferule (1939-1942): 371-394. cinetoplasmatiche(«Kinetoplasmakugein» Tuzet, o., 1950. Le spermatozoide dans la diMerton) delle cellule nutriciin Vagínu- serieanímale.RevueSuíssedeZoologíe,57: lus borellianus (Colosi). (Molí., Gastro- 433- 451. poda, Soleolifera). BollettinodeltaSocieta Tuzet, O.yMariaggi,J., 1951.Laspermato- ItalianadiBiologíaSperimentale, 40 (15): génése de Physa acuta Drapamaud. Bu- 911- 913. lletindelaSocíetéd'HístoíreNaturellede Quattrini, D. y Lanza, B., 1964b. La con- Toulouse, 86: 245-251. sistenza numérica deigruppi isogeni de- Watts, A. H. G., 1952. Spermatogenesis in Ilalineagerminale maschiledi Vaginulus the slugArionsubjuscus. JournaloJMor- borellianus (Colosi). (Molí., Gastropoda, phology, 91: 53-77. Soleolifera). Bollettino della Societa Ita- Yasuzumi, G., Tanaka, H., Tezuka, O. yNa- liana di Biología Sperimentale, 40 (19): KANOS, S., 1959.Theultrastructureofor- 1155- 1157. gandíesappearinginspermatidsandnu- Quattrini, D. y Lanza, B., 1964c. Osserva- tritive cells ofCípangopaludina malleata. zioni sullaovogenesie sullaspermatoge- ZeítschriftJür Zellforschung und Mikros- nesi di Vaginulus borellianus (Colosi). kopischeAnatomíe, 50: 632- 643. (Molí., Gastropoda,Soleolifera).Bollettino diZoología, 31 (2): 541-553, 4 est. Recibido el 9-III-1993 Aceptado el 20-XI-1993 168 IBERUS, 14 (2): 169-178, 1996 Presence of abnormal cilia in the mucosa of the male gonoduct of Bolinus (Murex) hrandaris (Gastropoda, Prosobranchia, Muricidae) Presencia de cilios anormales en la mucosa del gono- ducto masculino de Bolinus (Murex) hrandaris (Gastro- poda, Prosobranchia, Muricidae) María José AMOR* ABSTRACT Abnormal cilia, in which the bridges between the plasma membrane and the external microtubules are broken, are found in the mucosa of the male gonoduct of Bolinus (Murex) brandaris. As some authors have described this kind of ciliá in other species as artifacts produced bythe osmolahty ofthefixative médium, wefixedthe samples in diffe- rent osmolarity media, finding in all cases the presence of these abnormal cilia. A des- cription ofthe ultrastructure oftheabnormal ciliaofthe male gonoductof Bolinus(Murex) brandarisand suggestionsconcerning the role ofthe paddie ciliaare presented. RESUMEN En lamucosadelgonoductomasculinode Bolinus(Murex)brandarishansidodetectados cilios anormales, caracterizados por la ruptura de los puentes que unen los microtúbulos externosdel axonemay la membranaplasmática. Comoalgunosautores han descritoen otrasespeciesestaclasedecilioscomoartefactosproducidosporlaosmolaridaddelmedio de fijación empleado, hemos fijado muestras con diferentes osmolaridades obteniendo siemprelapresenciadeestosciliosanormales. Unadescripcióndelaultrastructuradelos cilios anormales del conducto deferente de Bolinus (Murex) brandaris, asícomo diferen- tessugerencias sobre su posible misión, son discutidas en el presentetrabajo. PALABRASCLAVE:Ciliosanormales,mediodefijación,gonoductomasculino,Bolinus(Murex)brandaris, Gastropoda,Muricidae. KEYWORDS: Abnormalcilia, fixativemédium,malegonoduct,Bolinus(Murex)brandaris, Gastropoda, Muricidae. INTRODUCTION Swellingsintheplasmamembraneof paddie cilia, while Heimler (1978) na- someciliawerefirstdescribedbyLuther med them discocilia. Nevertheless, other 85 years ago (Wasikand Mikolajczyk, authors refer to them indistinctly as 1991).As the shape ofcilia maybe chan- paddie ciliaordiscocilia (Dilly, 1977a,b; gedbecauseoftheseswellings,Tamarin, MateraandDavis, 1982andWasikand Lewis and Askey (1976), called them Mikolajczyk, 1991). * DepartmentofAnimalandVegetalCellBiology.UniversitatdeBarcelona. Avda.Diagonal,645,08022 Barcelona. 169 IBERUS, 14(2), 1996 They are frequently seen in marine althoughMateraandDavis(1982)have invertebrates, and several authors have observedtheminvivoinlightmicroscopy assigned various roles to them such as usingisotonicmédiumwith sea water in transport(DiLLY, 1977a,b;WasikandMi- the ciliated Cymatocilis convallaria, and KOLAJCZYK, 1991), a chemosensitive fuc- Heimler (1978) detected them in vivo tion (Materaand Davis, 1982), locomo- withaninterferencemicroscope. tion (Heimler, 1978) and even related The presence ofabnormal cilia in the themtoparasitism(Durfort,Bozzo,Po- male gonoduct of Bolinus (Murex) bran- QUET, Sacrista, GarcíaValero, Amor daris fixed in different osmolarity media and Ribes, 1990). They seem not to be and its possible evacuation role are dis- present in vertebrates, although swe- cussed inthispaper. llings in membrane of cilia have been described in the olfactory epithelium of MATERIALAND METHODS frogs and mice, and in dendrites of the crab Pagurus hirsutiusculiis, (Wasikand MiKOLAjczYK, 1991). Other authors sug- Specimens ofBolinus (Murex) branda- gest they are artifacts produced by the ris were collected off the Mediterranean difference in osmolarity of the fixative coast (St. Caries de la Rápita, Tarra- médium and the sea water (Ehlersand gona). Deferent ducts and penis were Ehlers, 1978; Short and Tamm, 1991), carefully removed and slices of about 300 Á were processed for transmission (Right page). Figure 1. Panoramic view ofthe mucosa ofthe gonoduct oíBolinus brandaris, with columnar cells (CO) showing cilia (C) sectioned at different levéis, microvilli (m) mito- chondria (M) and abundant glycogen granules (g). Agoblet cell (G) with granules at different degrees ofmaturity (asterisk) is also seen. (bb: basal bodies, C: Cilia, CO Columnar cells, G: goblet cell, g: glycogen granules, M; mitochondria m: microvilli, r: ciliary rootlets). Penis región. Fixed by hypertonic médium. Figure 2. Longitudinal section ofa cilium showing the characteristic striatedrootlet(r), the basalbody (bb), the transitionregión (T) andthe axoneme (a). Notice the bridges between the plasma membrane and the external microtubules at the beginning ofthe cilia (arrows). Deferent región. Fixed by tannic acid method. Hypotonic médium. Figure 3. Cross section ofcilia at different levéis showing rootlets (r), basal bodies (bb), transition región (T), cilia (C). Note bridges between the extemal microtubules and the plasmamembrane in the transition región (arrows). Abnormal cilia (star), and adhaerensjunc- tions between adjacent cells (asterisk) are also detected. Deferent región. Isotonic médium. Scalebars 1 |am. (Páginaderecha). Figura 1. Panorámicadelepiteliode lamucosadelgonoductomasculinode Bolinus brandaris en la región delpene,fijado en medio hipertónico, mostrando las células prismáticas (CO), con los cilios seccionados a diferentes niveles (C). microvilli (m), mitocon- drias (M), asi como abundantesgranulos deglucógeno (g). Puede observarse también lapre- sencia de una célula caliciforme (G) con granulos en diferentes grados de maduración en su interior (asterisco), (bb: corpúsculos básales; C: cilios; CO: células prismáticas; G: célula caliciforme; g: gránulas de glucógeno; M: mitocondrias; m: microvilli; r: raíces ciliares). Figura2. Cortelongitudinaldeunciliomorfológicamentenormaldelconductodeferentemos- trandolacaracterísticaestriacióndela raízciliar(r), elcorpúsculobasal(bb), laregión inter- media (T)yelaxonema (a). Pueden observarseasimismo lospuentes entre la membranaplas- mática y los microtúbulos externos en la zona delnacimiento del cilio (flechas). Fijación con ácido tánicoen medio hipotónico. Figura3. Corte transversaldeciliosdelconductodeferente a diferentes niveles mostrando las raíces ciliares (r), los corpúsculos básales (bb), la región intermedia (T) y los axonemas (a). Obsérvense lospuentes en la región intennedia entre los microtúbulosexternosylamembranaplasmática(flechas). Seobser\>atambién lapresenciade ciliosanonnales (estrella), asícomo algunas uniones adhaerens entrecélulas vecinas (asteris- co). Medio isotónico. Escalas 1pm. 170 . Amor: Presence ofabnormal cilia in the gonoduct oíBolinus brandaris vV ^/'^í" '". ' OfY 171 IBERUS, 14 (2), 1996 300 Á were processed for transmission thin sections (about 300 Á) were con- electrónmicroscopy. trasted with uranyl acétate and lead Aswe wanted to detectthe effects of citrate (Reynolds, 1963). theosmolarityofthefixationmédiumon For scanning electrón microscopy theshapeoftheciliainthemucosa,three observations, some dried samples were kindsoffixationmediawereprepared: passed through amyl acétate and dried -Hypotonic médium: Conventional tocriticalpoint. médium consisting of 2.5% gluta- To improve the observation of the raldehyde, 3.5% paraformaldehyde, buf- dispersión of the microtubules, samples fered with cacodylate buffer (pH 7.2- of 0.5 ¡iva were observed in a Hitachi H 7.4). Osmolarity: 454mOsmols. 800 MT, with an acceleration voltage -Isotonic médium: To the conventio- between 150-200KV, and a number 4 nal médium, we added NaCl progressi- objective diaphragm, although no new vely until obtaining an isotonic médium Information was obtained. The remai- with sea water (920 mOsmols, Short ning observations were made using andTamm, 1991). Philips EM200 and Philips EM 301 elec- -Hypertonic médium: We added trón microscopes, and a Hitachi S-2, 300 NaCltoanosmolarityof1279mOsmols. scanning electrón microscope in the To visualize the ciliary bridges Electron Microscope Service at the Uni- between the plasma membrane and versityofBarcelona. external microtubules, 1% tannic acid was added to the glutaraldehyde in some samples, as indicatedby Torikata RESULTS (1988). After washing with the same buffer, The mucosa of the gonoduct of Boli- all samples were postfixed with 1-2% nus (Murex) brandaris is formed by a co- Os04 and again washed with the same lumnar epithelium which shows abun- buffer. dant cilia and microvilli, and among The samples were dehydrated and these cells some goblet cells are found embedded in Spurr's resin (Spurr, (Amor, 1990a, b; Amor, 1992) (Fig. 1). 1969). Before ultrathinsectionswere cut, Cilia are longer in the penis región than 1/^msectionswere prepared and stained in the deferent región, and are set in the with 1% methylene blue-borax to select characteristic basal bodies that continué appropiate áreas for transmission elec- in the typical striated rootlets, longer in trónmicroscopyobservations. Theultra- the firstpart ofthe deferentductthanin (Rightpage). Figure4.Abnormalciliaobservedby scanningmicroscopy. Penis regiónhypoto- nic médium.A: panoramicview (C: normalcilia; asterisk: discocilia); B: detall ofanabnormal cilium with a subapical swelling (arrow); C: detall ofabnormal cilia with swellings in their central región ofthe cilia(arrows). Figure 5. Panoramic viewofabnormalciliaintransmission electrón microscopy. Notice the presence ofdisordered axonemes (arrowheads) as well as double axonemes (arrows), within the swellings ofthe plasma membrane (asterisk). Normal cilia(C)arealsoseen.Penisregión. Hypotonicmédium. Scalebars 1 |am. (Página derecha). Figura 4. Cilios anormales observados con microscopía electrónica de barrido. Región del pene. Medio hipotónico. A: vista panorámica (C: cilios normales. Asterisco:discocilios);B:detalledeuncilioanormalconunadilataciónsubapical(flecha); C: detalledeciliosanormalescondilatacionesenlaregiónmedia(flechas). Figura5. Vistapano- rámica de cilios normales (C)y cilios anormales con microscopía electrónica de transmisión (regióndelpene),pudiendoobservarse ladesorganización de losaxonemas(puntasdeflecha) ylapresenciadedosseccionesdeaxonema (flechas)dentrode lasdilatacionesdelamembra- naplasmática (asterisco). Mediohipotónico. Escalas 1 pm. 172 Amor: Presence ofabnormal cilia in the gonoduct ofBolinus brandaris 173 IBERUS, 14 (2), 1996 the rest of the gonoduct. This seems to appear in the ciliary membrane (Amor, be related with the higher density ofthe 1992) (Figs. 3, 5-11, 13 and 14). If these semenatthefirstlevéis ofthe gonoduct, swellings are found inthe central región where these smaller cilia and longer ro- of the cilium, only some bridges of the otlets could give more strength to eva- axoneme are broken, and some parts of cúate it, as we have polnted out pre- the axoneme are still connected to the viously (Amor, 1991). plasma membrane. However, if all At the transition región, cilia show^ bridges are broken, the axoneme the characteristic champagne-glass sha- appears free and separated from the ped (necklace)bridges (Fig. 2) described plasma membrane. In both cases, the byDentler (1981). Thesebridges, 5-6 in axoneme remains unaltered (Fig. 8 and number, are 36.6 nm long and 6.1 nm 14B). Incontrast, ifthese swellings occur thick, with a periodicity of 18.3 nm. In at the tip or near the tip of the cilium, the rest of the cilium, the bridges bet- the axoneme thencurves, and may form ween the plasma membrane and the ex- one or several loops inside the swelling ternal microtubules described by Den- of the membrane. Connections between tler (1990) are seen. These bridges are doblets of microtubules are often 17nm thick and 13.6 nm in length, with broken, and the axonemes become com- aperiodicityof40nm (Figs. 2,3). pletely disordered (Figs. 4-13 and 14A). These bridges are sometimes broken Inourmaterialwehave detected 23% of and swollen formations 1 /im wide swellings in the central región of the (Rightpage). Figure 6. Longitudinal section ofadiscocilium at the deferentduct level. Notice theswellingoftheplasmamembraneaswellasthedisorderingoftheaxonemeatthetopofthe cilium (arrow), while the rest ofthe axoneme remains unaltered. Isotonic médium. Figure 7. Differentarrangements ofthe axonemeinthe swellings oftheplasmamembrane inthe central región of the cilia. Glycogen granules (g) are also seen. Penis level. Tannic acid technique. Hypotonicmédium.Figure8. Detallofalongitudinal sectionofaswellingoftheplasmamem- brane in the central región ofa cilium (star). In this case, the axoneme (a) remains unaltered. Deferent región. Hypotonic médium. Figures 9-12. Cross sections ofabnormal cilia showing differentarrangements ofthe axoneme. Figure 9 shows the loops ofthe axoneme: «a» and «c» have the same orientation ofthe peripheric microtubules while «b» shows peripheric microtu- bules in the opposite direction (arrow). Deferent duct level. Hypertonic médium. Figure 13. Panoramic view of abnormal cilia (asterisks) showing microtubules undergoing dispersión (arrows). Besides, normal cilia are seen (C) as well as some glycogen granules (g). Hypotonic médium. Deferentlevel. Scale bars 1 |im. (Página derecha). Figura 6. Sección longitudinalde undiscociliodelconductodeferentemos- trando la dilatación de la membranaplasmática asícomo la desorganización delaxonema en elextremodelmismo (flecha), mientras elrestodelaxonemapermanece intacto. Medio isotó- nico. Figura 7. Diferentes disposiciones adoptadasporelaxonema en las dilataciones a nivel medio, en un corte delgonoducto a niveldelpene. También se observan algunosgranulos de glucógeno (g). Medio hipotónico. Acido tánico. Figura 8. Corte longitudinal de un cilio del conductodeferentepresentandounadilataciónaniveldela regiónmedia (estrella). Obsér\>ese comoenestecaso, elaxonema(a)noestáalterado. Mediohipotónico. Figuras9-12. Secciones transversales de varios cilios anormales mostrando las distintas disposiciones adoptadaspor elaxonema. En laFigura9,puedenobservarse lascurvaturasdelmismo: «a»y«c»presentan la misma orientación de los microtúbulosperiféricos mientras «b»presenta los microtúbulos periféricos orientados en sentido opuesto (flechas). Conducto deferente. Medio hipertónico. Figura 13. Imagenpanorámicadeciliosanormales(asteriscos)mostrandolosmicrotúbulosdel axonema en dispersión (flecha). A su lado se aprecian algunos cilios morfológicamente nor- males (C), asícomo algunosgranulosdeglucógeno (g). Conducto deferente. Medio hipotóni- co. Escalas 1pm. 174 Amor: Presence ofabnormal cilia in the gonoductofBolinus brandaris ITK^ \. ,3*5 »^*! 10 11 12 ~1' 4 «•^ * •*»^ '^ 175 IBERUS, 14 (2), 1996 Figure 14. Schematic representation ofthe arrangement ofmicrotubules in the abnormal cilia. A: swellings located in the tip ofthe cilium; 1: cross section, 2: longitudinal section. B: swe- Uingslocated inthe central regiónofthe cilium; a: axoneme, pm: plasmamembrane. Figura 14. Esquema de la disposición de los microtúbulos en los cilios anonnales. A: dilata- cionessituadasenelextremodelcilio; 1: sección transversal, 2: sección longitudinal. B: dila- tacionessituadas en la región mediadelcilio; a: axonema,pm: membranaplasmática. plasma membrane, and 65.7% of swe- diumhavenoeffectontheproportionor llings in the tip of the cilia. In the later configurationofthesepeculiarformations. case, a 59.2% could have two or more loops with an axoneme disorder, and only 6.5% do not show any axoneme DISCUSSION disorder. The rest of the ciliary shaft remainsidenticaltonormalcilia. Along the gonoduct of Bolinus These abnormal cilia seem not tobe (Murex) brandaris structure, there are distributed uniformly: there are áreas two populations of cilia: normal cilia whereabnormalcilia aremoreabundant with the characteristic configuration of (Fig. 4A), and theyrepresentabout4-6% rootlets, basal bodies and the 9-1-2 confi- ofthetotalcilia.Differentbuffersaswell guration of the axDneme (Amor, 1990a, as different osmolarities ofthe fixation b; Amor, 1992) ard a 4-6% of abnormal 176

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