Transcriptional analysis of the mtA idiomorph of Neurospora crassa identifies two genes in addition to mtA-1

Mol Gen Genet. 1996 Apr 10;250(6):767-74. doi: 10.1007/BF02172989.


In Neurospora crassa, mating and heterokaryon formation between opposite mating-types is controlled by a single locus with two alternate forms termed mt A and mt a. Previously, an open reading frame (mt A-1) that confers mating identity and heterokaryon incompatibility was characterized in the 5.3 kb mt A idiomorph. In this study, we describe the structural and transcriptional characterization of two additional genes in the mt A idiomorph, Mt A-2 and mt A-3. The 373 amino acid mt A-2 ORF has 23% identity to the SMR1 ORF of Podospora anserina. DNA sequence analysis of a mutation affecting ascospore to 129 amino acids. The 324 amino acids mt A-3 ORF has an HMG domain and shows 22% amino acid identity to SMR2 of P. anserina. Transcripts from mt A-2 and mt A-3 are constitutively expressed during both vegetative and sexual reproduction. The presence of upstream ORFs in the mt A-2 and mt A-3 transcripts suggests the possibility of post-transcriptional regulation of the expression mt A-2 and mt A-3 polypeptides.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Blotting, Northern
  • Chromosome Mapping
  • Cloning, Molecular
  • Consensus Sequence / genetics
  • DNA-Binding Proteins / chemistry
  • DNA-Binding Proteins / genetics*
  • Fungal Proteins / chemistry
  • Fungal Proteins / genetics*
  • Gene Expression Regulation, Fungal / genetics
  • Genes, Fungal / genetics*
  • Molecular Sequence Data
  • Neurospora crassa / chemistry
  • Neurospora crassa / genetics*
  • Open Reading Frames
  • Polymerase Chain Reaction
  • Sequence Alignment
  • Sequence Analysis
  • Transcription, Genetic / genetics


  • DNA-Binding Proteins
  • Fungal Proteins
  • MTA-1 protein, Neurospora crassa
  • MTA-2 protein, Neurospora crassa
  • MTA-3 protein, Neurospora crassa

Associated data

  • GENBANK/M33876