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Microtubule-dependent membrane dynamics in Ustilago maydis: Trafficking and function of Rab5a-positive endosomes

Vera Göhre1, Evelyn Vollmeister, Michael Bölker

  • 1Heinrich Heine University Düsseldorf; Center of Excellence on Plant Sciences (CEPLAS); Institute for Microbiology; Düsseldorf, Germany.

Communicative & Integrative Biology
|November 28, 2012
PubMed

Insights

Large endosomes carrying Rab5a (a G-protein) move along microtubules in Ustilago maydis, facilitating cell division, signaling, and mRNA transport for growth. These versatile endosomes act as crucial multipurpose platforms.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Mycology

Background:

  • Long-distance transport of vesicles along the cytoskeleton is essential for eukaryotic cellular processes like secretion and endocytosis.
  • Molecular motors facilitate the movement of secretory and endocytic vesicles along polarized microtubules.

Purpose of the Study:

  • To review the transport mechanism and biological functions of Rab5a-positive endosomes in the model microorganism Ustilago maydis.
  • To elucidate the role of these endosomes in various cellular processes throughout the Ustilago maydis life cycle.

Main Methods:

  • Review of existing literature on vesicle trafficking and motor proteins in Ustilago maydis.
  • Analysis of the functions associated with Rab5a-positive endosomes.

Main Results:

  • Rab5a-positive endosomes in Ustilago maydis are transported bi-directionally along microtubules by the motor proteins Kin3 and dynein (Dyn1/2).
  • These endosomes are involved in cytokinesis and pheromone signaling in haploid budding cells.
  • During filamentous growth, endosomes transport mRNA for maintaining polarity, likely enabling local protein translation.

Conclusions:

  • Rab5a-positive endosomes in Ustilago maydis are multifunctional organelles involved in diverse cellular processes.
  • The co-transport of mRNA by endosomes represents a novel mechanism supporting cellular polarity and growth.
  • Endosomes serve as versatile platforms for long-distance transport and localized cellular functions.
Keywords:
Basidiomyceteendosomesfilamentous fungimRNA transportmicrotubulespathogen

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