Sequence analysis and expression of the Penicillium chrysogenum nitrate reductase encoding gene (niaD)

摘要

The nitrate icduclu.se gene (niuD) of the filamentous fungus Penicillium cltnso/icinim encodes a protein of 864 aniino acids. The derived protein sequence shows IW'v and 12% sequence identity to the corresponding Aspergillus niger and A, nultihms proteins, respectively. The coding region of the Penicillium gene is interrupted by six small inlrons, as deduced by comparison with the ninl) sequences of A. nifer and A. nithilims, whereby the positions of the inlrons are perfectly conserved between these three fungal genes. Northern blot analysis indicated a 2.8 kb transcript and showed that expression of this gene is controlled at the level of niRNA accumulation depending on both induction by nitrate and nitrogen metabolite derepre.ssion. Induction of transcription of niaD was found lo be paralleled by expression of the major nitrogen regulatory gene nrc.