ASD4, a new GATA factor of Neurospora crassa, displays sequence-specific DNA binding and functions in ascus and ascospore development.
A new gene encoding a novel GATA factor, ASD4, of Neurospora crassa was isolated and demonstrated to possess one intron and to specify an open reading frame encoding a protein with 427 amino acid residues. The ASD4 protein contains a single GATA-type zinc finger and a putative coiled-coil domain. Unlike related proteins, DAL80 in yeast and NREB in Penicillium, ASD4 does not appear to be involved in regulation of nitrogen metabolism. An Asd-4 null mutant obtained by the rip procedure did not show any effect upon nitrogen control, but instead resulted in severe defects in ascus and ascospore genesis. The Asd-4 rip mutant is dominant to Asd-4+. A cross of the Asd-4 mutant with wild-type resulted in fruiting bodies that appeared to be normal macroscopically but which were complete devoid of asci and ascospores. Introduction of the Asd-4+ gene into the Asd-4 rip mutant corrected the defect in ascus and ascospore development in crosses with wild-type. Mobility shift assays demonstrated that ASD4 acts as a sequence-specific DNA binding protein and recognizes DNA fragments that contain GATA core elements. Gel filtration and cross-linking experiments revealed that the ASD4 protein exists as a tetramer in solution. These results suggest that the ASD4 protein functions positively as a transcriptional regulator of sexual development in Neurospora.
Feng
B
B
Department of Biochemistry, The Ohio State University, Columbus, Ohio 43210, USA.
Haas
H
H
Marzluf
G A
GA
D015152:Blotting, Northern; D003545:Cysteine / Q000737:chemistry / Q000235:genetics / Q000502:physiology; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology*; D016296:Mutagenesis; D009492:Neurospora crassa / Q000737:chemistry* / Q000235:genetics / Q000502:physiology*; D009584:Nitrogen / Q000378:metabolism; D017434:Protein Structure, Tertiary / Q000235:genetics; D020449:Repetitive Sequences, Amino Acid; D012996:Solutions; D013172:Spores, Fungal / Q000737:chemistry / Q000235:genetics / Q000502:physiology; D014170:Transformation, Genetic; D016335:Zinc Fingers / Q000235:genetics / Q000502:physiology
D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D012996:Solutions; D003545:Cysteine; D009584:Nitrogen