The Neurospora rca-1 Gene Complements an Aspergillus flbD Sporulation Mutant but Has No Identifiable Role in Neurospora Sporulation

Corresponding author: Daniel J. Ebbole, Dept. of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843-2132, dje0282{at}zeus.tamu.edu (E-mail).

Communicating editor: J. J. LOROS

The Aspergillus nidulans flbD gene encodes a protein with a Myb-like DNA-binding domain that is proposed to act in concert with other developmental regulators to control initiation of conidiophore development. We have identified a Neurospora crassa gene called rca-1 (regulator of conidiation in Aspergillus) based on its sequence similarity to flbD. We found that N. crassa rca-1 can complement the conidiation defect of an A. nidulans flbD mutant and that induced expression of rca-1 caused conidiation in submerged A. nidulans cultures just as was previously observed for overexpression of flbD. Thus, the N. crassa gene appears to be a functional homologue of A. nidulans flbD and this is the first demonstration of functional complementation of an A. nidulans sporulation defect using a gene from an evolutionarily distant fungus. However, deletion of the rca-1 gene in N. crassa had no major effect on growth rate, macroconidiation, microconidiation, or ascospore formation. The only phenotype displayed by the rca-1 mutant was straight or counterclockwise hyphal growth rather than the clockwise spiral growth observed for wild type. Thus, if rca-1 is involved in N. crassa development, its role is subtle or redundant.

This article has been cited by other articles:

				L. Bailey-Shrode and D. J. Ebbole The fluffy Gene of Neurospora crassa Is Necessary and Sufficient to Induce Conidiophore Development Genetics, April 1, 2004; 166(4): 1741 - 1749. [Abstract] [Full Text] [PDF]

				K. A. Borkovich, L. A. Alex, O. Yarden, M. Freitag, G. E. Turner, N. D. Read, S. Seiler, D. Bell-Pedersen, J. Paietta, N. Plesofsky, et al. Lessons from the Genome Sequence of Neurospora crassa: Tracing the Path from Genomic Blueprint to Multicellular Organism Microbiol. Mol. Biol. Rev., March 1, 2004; 68(1): 1 - 108. [Abstract] [Full Text] [PDF]

				F. Graïa, V. Berteaux-Lecellier, D. Zickler, and M. Picard ami1, an Orthologue of the Aspergillus nidulans apsA Gene, Is Involved in Nuclear Migration Events Throughout the Life Cycle of Podospora anserina Genetics, June 1, 2000; 155(2): 633 - 646. [Abstract] [Full Text]

				S. Lev, A. Sharon, R. Hadar, H. Ma, and B. A. Horwitz A mitogen-activated protein kinase of the corn leaf pathogen Cochliobolus heterostrophus is involved in conidiation, appressorium formation, and pathogenicity: Diverse roles for mitogen-activated protein kinase homologs in foliar pathogens PNAS, November 9, 1999; 96(23): 13542 - 13547. [Abstract] [Full Text] [PDF]

				L. A. Bailey and D. J. Ebbole The fluffy Gene of Neurospora crassa Encodes a Gal4p-Type C6 Zinc Cluster Protein Required for Conidial Development Genetics, April 1, 1998; 148(4): 1813 - 1820. [Abstract] [Full Text] [PDF]