Molecular and General Genetics MGG

, Volume 247, Issue 5, pp 583–590

A fungal actin-related protein involved in nuclear migration

  • Malcolm J. Robb
  • Margaret A. Wilson
  • P. John Vierula
Original Paper


The ro-4 mutant of the filamentous fungus Neurospora crassa forms distinctive colonies in which hyphae grow into rope-like aggregates. This unusual morphology coincides with a defect in hyphal nuclear migration. The ro-4 gene was cloned from a cosmid library by complementation of the closely linked pab-2 gene. The deduced 380 amino acid protein is most similar to the vertebrate actin-related protein/centractin. The R04 protein is not essential for cell viability, and new strains created by inducing point mutations at the ro-4 locus have a phenotype which is very similar to that of the original mutant. This study provides genetic evidence that an actin-related protein plays a role in nuclear motility. Since nuclear motility is believed to be a microtubule-dependent process, the ro-4 gene product may function as a component of the dynactin complex which activates force generation by cytoplasmic dynein.


Actin-related protein Nuclear migration Cytoskeleton Neurospora 


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Copyright information

© Springer-Verlag 1995

Authors and Affiliations

  • Malcolm J. Robb
    • 1
  • Margaret A. Wilson
    • 1
  • P. John Vierula
    • 1
  1. 1.Department of BiologyCarleton UniversityOttawaCanada

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