The ham-5, rcm-1 and rco-1 genes regulate hyphal fusion in Neurospora crassa
نویسندگان
چکیده
Mutants of Neurospora crassa unable to participate in vegetative hyphal fusion (anastomosis) were isolated and characterized. From this analysis, three genes, rcm-1, rco-1 and ham-5, were identified and shown to be required for hyphal fusion. The rcm-1 and rco-1 genes are homologues of the Saccharomyces cerevisiae SSN6 and TUP1 genes, which encode a dimeric transcription factor in yeast. We demonstrate that in N. crassa the rcm-1 and rco-1 genes are required for hyphal fusion and normal hyphal morphology, and influence both asexual and sexual development. The ham-5 gene encodes a 1686 amino acid protein with two putative WD40 domains, which might participate in protein-protein interactions. ham-5 deletion mutants had a reduced rate of hyphal extension and altered hyphal morphology, and were unable to produce the conidial anastomosis tubes that are required for hyphal fusion during colony initiation.
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