Hansenula polymorpha NMR2 and NMR4, two new loci involved in nitrogen metabolite repression.
In the yeast Hansenula polymorpha (Pichia angusta) nitrate assimilation is tightly regulated and subject to a dual control: nitrogen metabolite repression (NMR), triggered by reduced nitrogen compounds, and induction, elicited by nitrate itself. In a previous paper [Serrani, F., Rossi, B. and Berardi, E (2001) Nitrogen metabolite repression in Hansenula polymorpha: the nmrl-l mutation. Curr. Genet. 40, 243-250], we identified five loci (NMR1-NMR5) involved in NMR, and characterised one of them (NMR1), which likely identifies a regulatory factor. Here, we describe two more mutants, namely nmr2-1 and nmr4-1. The first one possibly identifies a regulatory factor involved in nitrogen metabolite repression by various nitrogen sources alternative to ammonium. The second one, apparently involved in ammonium assimilation, probably has sensor functions.
Rossi
Beatrice
B
Laboratorio di Genetica Microbica, DiSA, Università Politecnica delle Marche, Via Brecce Bianche, 60131 Ancona, Italy.
Manasse
Sonia
S
Serrani
Federica
F
Berardi
Enrico
E
D005656:Fungal Proteins / Q000378:metabolism*; D005786:Gene Expression Regulation; D005809:Genes, Regulator; D009584:Nitrogen / Q000378:metabolism*; D010843:Pichia / Q000235:genetics* / Q000378:metabolism*; D000644:Quaternary Ammonium Compounds / Q000378:metabolism; D012097:Repressor Proteins
D005656:Fungal Proteins; D000644:Quaternary Ammonium Compounds; D012097:Repressor Proteins; D009584:Nitrogen