Interaction between Major Nitrogen Regulatory Protein NIT2 and Pathway-Specific Regulatory Factor NIT4 Is Required for Their Synergistic Activation of Gene Expression in Neurospora crassa
AUTOR(ES)
Feng, Bo
FONTE
American Society for Microbiology
RESUMO
In Neurospora crassa, the major nitrogen regulatory protein, NIT2, a member of the GATA family of transcription factors, controls positively the expression of numerous genes which specify nitrogen catabolic enzymes. Expression of the highly regulated structural gene nit-3, which encodes nitrate reductase, is dependent upon a synergistic interaction of NIT2 with a pathway-specific control protein, NIT4, a member of the GAL4 family of fungal regulatory factors. The NIT2 and NIT4 proteins both bind at specific recognition elements in the nit-3 promoter, but, in addition, we show that a direct protein-protein interaction between NIT2 and NIT4 is essential for optimal expression of the nit-3 structural gene. Neurospora possesses at least five different GATA factors which control different areas of cellular function, but which have a similar DNA binding specificity. Significantly, only NIT2, of the several Neurospora GATA factors examined, interacts with NIT4. We propose that protein-protein interactions of the individual GATA factors with additional pathway-specific regulatory factors determine each of their specific regulatory functions.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=108983Documentos Relacionados
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