Yeast Endocytic Adaptor AP-2 Binds the Stress Sensor Mid2 and Functions in Polarized Cell Responses
| Autor: | Chapa-y-Lazo, Bernardo, Allwood, Ellen G, Smaczynska-de Rooij, Iwona I, Snape, Mary L, Ayscough, Kathryn R |
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| Jazyk: | angličtina |
| Rok vydání: | 2014 |
| Předmět: |
Membrane Glycoproteins
Saccharomyces cerevisiae Proteins Mid2 Adaptor Protein Complex 2 Intracellular Signaling Peptides and Proteins Cell Polarity Membrane Proteins Original Articles Saccharomyces cerevisiae Clathrin Endocytosis pheromone stress pseudohyphae Cell Wall Candida albicans Saccharomycetales polarity Protein Binding |
| Zdroj: | Traffic (Copenhagen, Denmark) |
| ISSN: | 1600-0854 1398-9219 |
| Popis: | The AP-2 complex is a heterotetrameric endocytic cargo-binding adaptor that facilitates uptake of membrane proteins during mammalian clathrin-mediated endocytosis. While budding yeast has clear homologues of all four AP-2 subunits which form a complex and localize to endocytic sites in vivo, the function of yeast AP-2 has remained enigmatic. Here, we demonstrate that AP-2 is required for hyphal growth in Candida albicans and polarized cell responses in Saccharomyces cerevisiae. Deletion of APM4, the cargo-binding mu subunit of AP-2, causes defects in pseudohyphal growth, generation of a mating projection and the cell wall damage response. In an apm4 null mutant, the cell wall stress sensor Mid2 is unable to relocalize to the tip of a mating projection following pheromone addition, or to the mother bud neck in response to cell wall damage. A direct binding interaction between Mid2 and the mu homology domain of Apm4 further supports a model in which AP-2 binds Mid2 to facilitate its internalization and relocalization in response to specific signals. Thus, Mid2 is the first cargo for AP-2 identified in yeast. We propose that endocytic recycling of Mid2 and other components is required for polarized cell responses ensuring cell wall deposition and is tightly monitored during cell growth. |
| Databáze: | OpenAIRE |
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