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Mast, a conserved microtubule-associated protein required for bipolar mitotic spindle organization

C L Lemos1, P Sampaio, H Maiato

  • 1Laboratório de Genética Molecular da Mitose, Instituto de Biologia Molecular e Celular, Universidade do Porto, R.Campo Alegre, 823, 4150-180 Porto, Portugal.

The EMBO Journal
|July 19, 2000
PubMed

Insights

The study identifies the multiple asters (mast) gene, crucial for cell division. Mutations cause abnormal cell structures, highlighting Mast

Area of Science:

  • Cell Biology
  • Genetics
  • Molecular Biology

Background:

  • Mitotic abnormalities can lead to polyploidy and aneuploidy.
  • Microtubule-organizing centers (MTOCs) are critical for spindle formation.
  • The function of novel proteins in mitosis requires elucidation.

Purpose of the Study:

  • To identify and characterize the function of the novel gene multiple asters (mast).
  • To investigate the role of the Mast protein in mitotic processes.
  • To understand the evolutionary conservation and localization of Mast.

Main Methods:

  • Mutational analysis in Drosophila melanogaster.
  • Immunofluorescence microscopy using anti-Mast antibodies.
  • Analysis of enhanced green fluorescent protein-Mast fusion proteins.
  • Microtubule-binding assays.

Main Results:

  • The multiple asters (mast) gene encodes a 165 kDa protein.
  • Mast mutant neuroblasts exhibit severe mitotic defects, including abnormal spindle formation.
  • Mast protein localizes to centrosomes, spindle, centromeres, and spindle midzone during mitosis.
  • Mast is a microtubule-associated protein with high affinity for polymerized microtubules.

Conclusions:

  • Mast plays a critical role in centrosome separation and bipolar mitotic spindle organization.
  • The Mast protein family is evolutionarily conserved from yeast to humans.
  • Mast is essential for accurate chromosome segregation during cell division.

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