Beyond 9+0: noncanonical axoneme structures characterize sensory cilia from protists to humans

Gluenz, E. , Höög, J. L., Smith, A. E., Dawe, H. R., Shaw, M. K. and Gull, K. (2010) Beyond 9+0: noncanonical axoneme structures characterize sensory cilia from protists to humans. FASEB Journal, 24(9), pp. 3117-3121. (doi: 10.1096/fj.09-151381) (PMID:20371625) (PMCID:PMC2923350)

Abstract

The intracellular amastigote stages of parasites such as Leishmania are often referred to as aflagellate. They do, however, possess a short axoneme of cryptic function. Here, our examination of the structure of this axoneme leads to a testable hypothesis of its role in the cell biology of pathogenicity. We show a striking similarity between the microtubule axoneme structure of the Leishmania mexicana parasite infecting a macrophage and vertebrate primary cilia. In both, the 9‐fold microtubule doublet symmetry is broken by the incursion of one or more microtubule doublets into the axoneme core, giving rise to an architecture that we term here the 9v (variable) axoneme. Three‐dimensional reconstructions revealed that no particular doublet initiated the symmetry break, and moreover it often involved 2 doublets. The tip of the L. mexicana flagellum was frequently intimately associated with the macrophage vacuole membrane. We propose that the main function of the amastigote flagellum is to act as a sensory organelle with important functions in host‐parasite interactions and signaling in the intracellular stage of the L. mexicana life cycle.— Gluenz, E., Höög, J. L., Smith, A. E., Dawe, H. R., Shaw, M. K., Gull, K. Beyond 9+0: noncanonical axoneme structures characterize sensory cilia from protists to humans.

• Item Type: Articles
• Additional Information: This work was funded by the Wellcome Trust, the Beit Memorial Fellowships for Medical Research, the Jackson Scholarship Fund (Merton College Oxford, to A.E.S.), an EMBO long‐term fellowship (to J.L.H.), and the E. P. Abraham Trust. K.G. held a Wellcome Trust Principal Research Fellowship, H.R.D. is a Beit Memorial Fellow, and J.L.H. is a Sir Henry Wellcome Fellow. The Boulder Laboratory for 3D Electron Microscopy of Cells is supported by National Institutes of Health Biotechnology grant RR00592 to A. Hoenger (University of Colorado, Boulder, CO, USA).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Gluenz, Dr Eva
• Authors: Gluenz, E., Höög, J. L., Smith, A. E., Dawe, H. R., Shaw, M. K., and Gull, K.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: FASEB Journal
• Publisher: Federation of American Society of Experimental Biology (FASEB)
• ISSN: 0892-6638
• ISSN (Online): 1530-6860
• Published Online: 06 April 2010