The MAL protein is crucial for proper membrane condensation at the ciliary base, which is required for primary cilium elongation

The base of the primary cilium contains a zone of condensed membranes whose importance is not known. Here, we have studied the involvement of MAL, a tetraspanning protein that exclusively partitions into condensed membrane fractions, in the condensation of membranes at the ciliary base and investiga...

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Detalles Bibliográficos
Autores: Reales, E., Bernabé-Rubio, M., Casares-Arias, J., Rentero, C., Fernández-Barrera, J., Rangel Sánchez, Laura, Correas Hornero, María Isabel, Enrich, C., Andrés, G., Alonso, M.A.
Tipo de recurso: artículo
Fecha de publicación:2015
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/675808
Acceso en línea:http://hdl.handle.net/10486/675808
https://dx.doi.org/10.1242/jcs.164970
Access Level:acceso abierto
Palabra clave:Centrosome
Condensed membranes
MAL
Primary ciliogenesis
Biología y Biomedicina / Biología
Descripción
Sumario:The base of the primary cilium contains a zone of condensed membranes whose importance is not known. Here, we have studied the involvement of MAL, a tetraspanning protein that exclusively partitions into condensed membrane fractions, in the condensation of membranes at the ciliary base and investigated the importance of these membranes in primary cilium formation. We show that MAL accumulates at the ciliary base of epithelial MDCK cells. Knockdown of MAL expression resulted in a drastic reduction in the condensation of membranes at the ciliary base, the percentage of ciliated cells and the length of the cilia, but did not affect the docking of the centrosome to the plasma membrane or produce missorting of proteins to the pericentriolar zone or to the membrane of the remaining cilia. Rab8 (for which there are two isoforms, Rab8A and Rab8b), IFT88 and IFT20, which are important components of the machinery of ciliary growth, were recruited normally to the ciliary base of MAL-knockdown cells but were unable to elongate the primary cilium correctly. MAL, therefore, is crucial for the proper condensation of membranes at the ciliary base, which is required for efficient primary cilium extension