A fungal actin-related protein involved in nuclear migration.
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 RO4 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.
Robb
M J
MJ
Department of Biology, Carleton University, Ottawa, Canada.
Wilson
M A
MA
Vierula
P J
PJ
D000199:Actins / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D001483:Base Sequence; D002467:Cell Nucleus / Q000502:physiology; D003001:Cloning, Molecular; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D009492:Neurospora crassa / Q000502:physiology
D000199:Actins; D005656:Fungal Proteins