Biogenesis of the Inner Membrane Complex Is Dependent on Vesicular Transport by the Alveolate Specific GTPase Rab11B

PLoS Pathogens

Carolina Agop-Nersesian¹  Markus Meissner²  Saskia Egarter²  Gordon Langsley³  David J. P. Ferguson⁴  Bernardo J. Foth⁵ 

[1] Department of Infectiology, Parasitology, University Hospital Heidelberg, Heidelberg, Germany;Division of Infection & Immunity and Wellcome Centre for Parasitology, Faculty of Biomedical and Life Sciences, University of Glasgow, Glasgow, United Kingdom;Laboratoire de Biologie Cellulaire Comparative des Apicomplexes, Institut Cochin, Inserm, U567, CNRS, UMR 8104, Faculté de Médecine Paris V – Hôpital Cochin, Paris, France;Nuffield Department of Clinical Laboratory Science, Oxford University, Oxford, United Kingdom;School of Biological Sciences, Nanyang Technological University, Singapore, Republic of Singapore

关键词: Biosynthesis;    Microtubules;    Cell cycle;    cell division;    Cell membranes;    Parasite replication;    Cellular structures;    organelles;    Apicomplexa;    Golgi apparatus;   

DOI  :  10.1371/journal.ppat.1001029

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

Apicomplexan parasites belong to a recently recognised group of protozoa referred to as Alveolata. These protists contain membranous sacs (alveoli) beneath the plasma membrane, termed the Inner Membrane Complex (IMC) in the case of Apicomplexa. During parasite replication the IMC is formed de novo within the mother cell in a process described as internal budding. We hypothesized that an alveolate specific factor is involved in the specific transport of vesicles from the Golgi to the IMC and identified the small GTPase Rab11B as an alveolate specific Rab-GTPase that localises to the growing end of the IMC during replication of Toxoplasma gondii. Conditional interference with Rab11B function leads to a profound defect in IMC biogenesis, indicating that Rab11B is required for the transport of Golgi derived vesicles to the nascent IMC of the daughter cell. Curiously, a block in IMC biogenesis did not affect formation of sub-pellicular microtubules, indicating that IMC biogenesis and formation of sub-pellicular microtubules is not mechanistically linked. We propose a model where Rab11B specifically transports vesicles derived from the Golgi to the immature IMC of the growing daughter parasites.

【 授权许可】

CC BY