S. Masloff et al., The pro1(+) gene from Sordaria macrospora encodes a C-6 zinc finger transcription factor required for fruiting body development, GENETICS, 152(1), 1999, pp. 191-199
During sexual morphogenesis, the filamentous ascomycete Sordaria macrospora
differentiates into multicellular fruiting bodies called perithecia. Previ
ously it has been shown that this developmental process is under polygenic
control. To further understand the molecular mechanisms involved in fruitin
g body formation, we generated the protoperithecia forming mutant pro1, in
which the normal development of protoperithecia into perithecia has been di
srupted. We succeeded in isolating a cosmid clone from an indexed cosmid li
brary, which was able to complement the pro1(-) mutation. Deletion analysis
, followed by DNA sequencing, subsequently demonstrated that fertility was
restored to the pro1 mutant by an open reading frame encoding a 689-amino-a
cid polypeptide, which we named PRO1. A region from this polypeptide shares
significant homology with the DNA-binding domains found in fungal Ca zinc
finger transcription factors, such as the GAL4 protein from yeast. However,
other typical regions of Cg zinc finger proteins, such as dimerization ele
ments, are absent in PRO1. The involvement of the pro1(+) gene in fruiting
body development was further confirmed by trying to complement the mutant p
henotype with in vitro mutagenized and truncated versions of the pro1 open
reading frame. Southern hybridization experiments also indicated that pro1(
+) homologues are present in other sexually propagating filamentous ascomyc
etes.