Identification of genes displaying differential expression in the nuc-2 mutant strain of the mold Neurospora crassa grown under phosphate starvation.

Subtractive hybridization was used to isolate transcripts up-regulated in the nuc-2 mutant strain of Neurospora crassa grown under phosphate starvation. Following differential screening, 66 cDNA clones of the total enriched were screened in a second round by reverse Northern hybridization. The 17 cDNA candidates displaying visual positive differential expression were sequenced, and functional grouping identified putative proteins possibly involved in diverse cellular processes as, for example, protein synthesis, signal transduction mechanisms, and transport facilitation. Four of them, confirmed by both virtual and Northern blot analyses, revealed genes involved in the initiation of mRNA translation that are significantly up-regulated in the nuc-2 mutant strain, which may be relevant to a further understanding of the molecular events involved in the phosphorus sensing in N. crassa.