NITROGEN REGULATION OF BLUE LIGHT-INDUCIBLE GENES IN NEUROSPORA-CRASSA

Sexual and asexual differentiation of Neurospora crassa are influenced by nitrogen availability and blue light. Nitrogen limitation induces the production of protoperithecia on solid medium and conidia in liquid medium. Both developmental processes are stimulated by blue light. We have analysed changes in mRNA levels for a variety of light-inducible genes (al, bli and con) under conditions of nitrogen limitation. We show that the photoregulated genes al-1, al-2, bli-4, bli-7, con-5 and con-10 are also regulated by nitrogen limitation. These genes exhibited nitrogen regulation in the nonphotoresponsive mutant strains wc-1 and wc-2. Therefore, the wc-1 and wc-2 gene products, although necessary for photoregulation of these al, bli and con genes, are not required for nitrogen regulation.