| Title | Structure and Function of the Mating-type Locus in the Homothallic Ascomycete, Didymella zeae-maydis |
|---|---|
| Author | Sung-Hwan Yun1*, Olen C. Yoder2,3, and B. Gillian Turgeon2 |
| Address | 1Department of Medical Biotechnology, Soonchunhyang University, Asan 336-745, Republic of Korea, 2Department of Plant Pathology and Plant-Microbe Biology, Ithaca, NY 14853, USA, 3Celgene Corp., 10300 Campus Point Drives, San Diego, CA 92121, USA |
| Bibliography | Journal of Microbiology, 51(6),814–820, 2013, |
| DOI | 10.1007/s12275-013-3465-2 |
| Key Words | Didymella zeae-maydis, mating-type genes, sexual reproduction, homothallism |
| Abstract | Homothallic Didymella zeae-maydis undergoes sexual reproduction by selfing. Sequence analysis of the mating type (MAT) locus from this fungus revealed that MAT carries both MAT1-1-1 and MAT1-2-1 genes found in heterothallic Dothideomycetes, separated by ~1.0 kb of noncoding DNA. To understand the mechanistic basis of homothallism in D. zeae-maydis, each of the MAT genes was deleted and the effects on selfing and on ability to cross in a heterothallic manner were determined. The strain carrying an intact MAT1-1-1 but defective MAT1-2-1 gene (MAT1-1-1;ΔMAT1-2-1) was self-sterile, however strains carrying an intact MAT1-2-1 but defective MAT1-1-1 gene (ΔMAT1-1-1;MAT1-2-1), when selfed, showed delayed production of a few ascospores. Attempts to cross the two MAT deletion strains yielded fewer ΔMAT1-1-1;MAT1-2-1 than MAT1-1-1;ΔMAT1-2-1 progeny and very few ascospores overall compared to WT selfs. This study demonstrates that, as in the other homothallic Dothideomycetes, both MAT genes are required for full fertility, but that, in contrast to other cases, the presence of a single MAT1-2-1 gene can induce homothallism, albeit inefficiently, in D. zeae-maydis. |