title: Molecular characterization of the qa-4 gene of Neurospora crassa.
abstract: The qa-4 gene of Neurospora crassa encodes 3-dehydroshikimate dehydratase, which catalyzes the third step of the quinic acid (qa) catabolic pathway. The enzyme has previously been purified and characterized as a monomer of approx. 37 kDal. The nucleotide sequence of the qa-4 gene is presented here and the amino acid composition and tentative NH2-terminal sequence confirm the identification of the coding region within the qa-4 DNA sequence. There are no introns in the qa-4 coding region. By S1 nuclease mapping and primer extension analysis three distinct regions of transcription initiation were identified. Heterogeneity was also observed in the 3' ends of qa-4 mRNA. 5' and 3' untranslated regions of the qa-4 gene were compared with the corresponding regions in other Neurospora genes. Genomic blot analysis of twenty previously isolated qa-4 mutants revealed that two mutants, MC150 and MC191, have restriction patterns altered from wild type. In each strain the alteration occurs in the 3' half of the qa-4 coding region.
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D004271:DNA, Fungal / Q000235:genetics; D005796:Genes; D005800:Genes, Fungal; D008040:Genetic Linkage; D006836:Hydro-Lyases / Q000235:genetics*; D009491:Neurospora / Q000235:genetics*; D009492:Neurospora crassa / Q000235:genetics*; D011801:Quinic Acid; D012333:RNA, Messenger / Q000235:genetics
chemical_list: D004271:DNA, Fungal; D012333:RNA, Messenger; D011801:Quinic Acid; C044921:3-dehydroshikimate dehydratase; D006836:Hydro-Lyases