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Mechanics of Microsporidian Polar Tube Firing

Pattana Jaroenlak1, Mahrukh Usmani1, Damian C Ekiert2,3

  • 1Department of Cell Biology, New York University School of Medicine, New York, NY, USA.

Experientia Supplementum (2012)
|May 11, 2022
PubMed

Insights

Microsporidia use a unique, harpoon-like polar tube (PT) to infect host cells. This coiled organelle rapidly transforms into a long tube, delivering infectious cargo for microsporidian replication.

Area of Science:

  • Microbiology
  • Cell Biology
  • Parasitology

Background:

  • Microsporidia are obligate intracellular parasites.
  • They possess reduced genomes and require host cells for replication.
  • Infection is initiated by a specialized invasion organelle, the polar tube (PT).

Purpose of the Study:

  • To discuss the structure of the microsporidian polar tube (PT).
  • To explain the mechanics of the PT firing process.
  • To elucidate how the PT facilitates the movement of material from the spore.

Main Methods:

  • Review of existing literature on microsporidian polar tube structure and function.
  • Analysis of the biophysical mechanisms underlying polar tube firing.
  • Examination of the role of the polar tube in infectious cargo delivery.

Main Results:

  • The polar tube (PT) is a coiled organelle within microsporidian spores.
  • Upon germination, the PT undergoes rapid, large-scale conformational changes.
  • The PT forms a long tube, delivering infectious cargo into host cells on a millisecond timescale.

Conclusions:

  • The polar tube (PT) is a key, characteristic organelle of microsporidia.
  • Its rapid firing mechanism is essential for host cell invasion and parasite replication.
  • Understanding PT structure and mechanics is crucial for comprehending microsporidian pathogenesis.
Keywords:
Cargo transportExtruded PTNuclear deformationPTPT configurationPT firingPT firing dynamicsPT structuresPolar tubeSpore germination

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