Analysis of the contraction of an organelle using its birefringency: the R‐fibre of the Ceratium (Dinoflagellate) flagellum*

Cell Biology International - Tập 28 - Trang 387-396 - 2004
Hidemi Sato1, Claude Greuet2, Monique Cachon2, Jacky Cosson2
1Nagano University, Shimonogo, Ueda-Shi, Nagano, 386-12, Japan
2U.M.R. 7009 du CNRS, Biologie du Développement, Observatoire Océanologique de Villefranche-sur-Mer, 06230 Villefranche-sur-mer, France

Tóm tắt

AbstractSome organelles responsible for contraction consist of bundles of 2–4 nm filaments called nanofilaments. Such organelles are present in the longitudinal flagellum of Ceratium (Dinoflagellate): the R‐fibre is the motor system for contraction and parallels the axoneme, which is responsible for wave generation. We used a highly sensitive polarization microscope developed by one of the authors to measure the birefringence of these nanofilament bundles during contraction in vivo. Our results show that the R‐fibre gives a highly birefringent signal, retarding the polarization to much the same extent irrespective of the direction of polarization. By rotating the axis of the microscope compensator we confirmed that the birefringence is positive, suggesting that the bundles run parallel to the longitudinal axis of the flagellum. Conversely, when the compensator was rotated contrary to the direction of retardation, the bundle appeared dark (except when the organelle was in a fully contracted state). Experiments performed on detergent‐treated and ATP‐reactivated flagella show that a portion of the flagella regained activity with the addition of ATP in the presence of low Ca2+ concentrations. This demonstrates the ability to reactivate flagellar motility after permeabilization and that axonemal microtubules were not responsible for the strong flagellar birefringence. Combined with complementary data from DIC microscopy of demembranated flagella and electron microscopy, these findings have led to the development of a model of the R‐fibre and a comparison with other types of birefringent nanofilament bundles, such as the myoneme of Acantharia.

Tài liệu tham khảo

10.1038/229127a0 10.1126/science.1085544 10.1126/science.142.3596.1169 10.1002/cm.970170406 Cachon J, 1964, Leptospathium navicula nov. gen. nov. sp. et Leptophyllus dasypus nov. gen. nov. sp, Péridiniens Noctilucidae Kent du plancton néritique de Villefranche‐sur‐mer, Bull Inst Océanogr Monaco, 62, 1 10.1016/0303-2647(81)90038-1 10.1002/cm.970030106 10.1016/0248-4900(88)90055-X 10.1016/0248-4900(91)90063-S 10.1016/0248-4900(92)90192-4 10.1111/j.1768-322X.1989.tb00770.x 10.1016/0248-4900(88)90050-0 Febvre J, 1971, Le myonème d'Acanthaire: essai d'interprétation ultrastructurale et cinétique, Protistologica, 379 10.1016/0248-4900(88)90012-3 Greuet C, 1967, Organisation ultrastructurale du tentacule d' Erythropsis pavillardi Kofoïd et Swezy, Péridinien Warnowiidae Lindemann, Protistologica, 335 Greuet C, 1981, Microtubules in microorganisms, 21 10.1002/cm.970060221 Hartshorne N.H, 1960, A handbook for chemists and others, 76 10.1007/978-1-4757-6925-8 10.1111/j.1550-7408.1981.tb02860.x Maruyama T, 1982, Fine structure of the longitudinal flagellum in Ceratium tripos, a marine dinoflagellate, J Cell Sci, 58, 109, 10.1242/jcs.58.1.109 10.1111/j.1550-7408.1985.tb03023.x Maruyama T, 1985, Extraction model of the longitudinal flagellum of Ceratium tripos (Dinoflagellida): reactivation of flagellar retraction, J Cell Sci, 75, 313, 10.1242/jcs.75.1.313 Lecointre G, 2001, Classification phylogenetique du vivant 10.1111/j.1529-8817.1989.tb00114.x 10.1126/science.202.4371.975 10.1083/jcb.67.3.501 10.1267/ahc.24.343 Soyer M.‐O, 1968, Présence de formations fibrillaires complexes chez Noctiluca miliaris Suriray et discussion de leur rôle dans la motilité de ce Dinoflagellé, CR Acad Sci Paris, 266, 2428 10.1007/BF00340048 10.1016/S0022-5320(69)90033-1 Swann M.M, 1950, Refinments in polarized light microscopy, J Exp Biol, 27, 226, 10.1242/jeb.27.2.226 10.1083/jcb.68.3.497
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Cell Biology International

Tập 28

387-396

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