Abstract: An isolated DNA having the promoter sequence of the hex gene of P. chrysogenum or a DNA fragment that is hybridizable to the complement of the promoter sequence under stringent conditions and is capable of directing expression of DNA downstream of the fragment in P. chrysogenum. Also a process for promoting expression of a coding sequence of interest in a microorganism using the isolated DNA and a process to block expression of a gene of interest in a microorganism using the isolated DNA are disclosed.

Abstract: The invention relates to promoters of the genes glutamate dehydrogenase, &bgr;-acetylhexosaminidase and &ggr;-actin and their use in systems of expression, secretion and anti-sense of filamentary fungi. The invention also relates to the use of the promoters of the genes which code: (I) glutamate dehydrogenase NADP depending (EC.1.4.1.4) of Penicillium chrysogenum, (II) &ggr;-N-actylhexosaminidase (EC.3.2.1.52) of Penicillium chrysogenum and (III) &ggr;-actin of Penicillium chrysogenum and Acrimonium chrysogenum, which can be used for the construction of potent vectors of expression and secretion useful both for P. chrysogenum and for A. chrysogenum and related species. These promoters can also be used for blocking the genic expression through anti-sense construction. Under the control of the above mentioned promoters, it is possible to conduct the expression of other genes in filamentary fungi, thereby increasing the production of antibiotics and/or proteins inherent to the same.