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Updated: Aug 9, 2026
07:47
Microscopy of Fission Yeast Sexual Lifecycle
Published on: March 9, 2016
Multiple genes encoding pheromones and a pheromone receptor define the B beta 1 mating-type specificity in
L J Vaillancourt1, M Raudaskoski, C A Specht
1Department of Microbiology and Molecular Genetics, L. P. Markey Center for Molecular Genetics, University of Vermont, Burlington 05405, USA.
Genetics
|June 1, 1997
Summary
The wood-rotting mushroom Schizophyllum commune has two mating type loci, B alpha and B beta, each with pheromone and receptor genes. These genes control sexual reproduction, with evidence suggesting a common ancestor for both loci.
Area of Science:
- Mycology
- Genetics
- Molecular Biology
Background:
- Mating in the fungus Schizophyllum commune is controlled by multiple B mating types.
- These mating types are regulated by genes located in two distinct loci: B alpha and B beta.
- Sexual morphogenesis is initiated by mating type incompatibility at either locus.
Purpose of the Study:
- To investigate the genetic makeup and function of the B beta mating type locus in Schizophyllum commune.
- To compare the B beta locus with the previously studied B alpha locus.
- To explore the evolutionary origins of these mating type genes.
Main Methods:
- Gene prediction and sequence analysis of the B beta 1 locus.
- Comparison of DNA sequences between B alpha 1 and B beta 1 loci.
- Functional inference based on homology to known mating pathways.
Main Results:
- The B beta 1 locus contains at least three pheromone genes and one pheromone receptor gene.
- These B beta genes function analogously to those in the B alpha locus but are specific to the B beta series.
- Sequence comparison suggests that the B alpha and B beta loci share a common ancestral sequence.
Conclusions:
- The B beta locus plays a crucial role in regulating mating compatibility, similar to the B alpha locus.
- The structural and sequence similarities between B alpha and B beta loci provide insights into the evolution of mating type genes in S. commune.
- This study elucidates the genetic mechanisms underlying mating in a key model basidiomycete fungus.
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