Characterization of mating-type idiomorphs suggests that Morchella importuna, Mel-20 and M. sextelata are heterothallic
Morels (Morchella spp.) are highly prized for their culinary qualities and intensively collected worldwide by mycophiles. Morels are divided into three clades by phylogenetic analyses: black morels, yellow morels and the rufobrunnea clade. Morchella importuna, Mel-20 and M. sextelata are included in the black morel clade and are widely distributed in Yunnan province, China. M. importuna and M. sextelata have been artificially cultured in recent years, but their life cycles and reproductive systems are still poorly understood, which delays the progress of morel cultivation. In this study, the genomes of two ascospore isolates of M. importuna with opposite mating-type were sequenced and two idiomorphs, MAT1–1 and MAT1–2, were identified. The MAT1–2 idiomorph was 6.7 kb in length containing a single MAT1–2-1 gene, and the MAT1–1 idiomorph was 10.5 kb containing a MAT1–1-1 gene and two other open reading frames (ORFs), GME3123 and GME3124. These ORFs differed greatly from the homologues of previously published mating-type genes; therefore, we speculate that they are novel mating genes found only in morels. Single-ascospore populations of M. importuna, M. sextelata and Mel-20 were analysed, and the result indicated that the ratios of MAT1–1- and MAT1–2-harbouring idiomorphs were not significantly different from a 1:1 ratio. The results suggest that these three black morels are heterothallic.
KeywordsMorel MAT1–1-1 MAT1–2-1 Single-ascospore population
This work was supported by the National Natural Science Foundation Program of PR China (31460014) and the China Agriculture Research System (CARS-24).
- Chilvers MI, Jones S, Meleca J, Peever TL, Pethybridge SJ, Hay FS (2014) Characterization of mating type genes supports the hypothesis that Stagonosporopsis chrysanthemi is homothallic and provides evidence that Stagonosporopsis tanaceti is heterothallic. Currr Genet 60:295–302CrossRefGoogle Scholar
- Coppin E, Debuchy R, Arnaise S, Picard M (1997) Mating types and sexual development in filamentous ascomycetes. Microbiol. Mol Biol Rev 61:411–428Google Scholar
- Du XH, Zhao Q, Yang ZL (2014) Diversity, evolutionary history and cultivation of morels: a review. Mycosystema 33:183–197Google Scholar
- Hutchinson MI, Powell AJ, Tsang A, O’Toole N, Berka RM, Barry K, Grigoriev IV, Natvig DO (2016) Genetics of mating in members of the Chaetomiaceae as revealed by experimental and genomic characterization of reproduction in Myceliophthora heterothallica. Fungal Genet Biol 86:9–19CrossRefPubMedGoogle Scholar
- Miller SC(2005) Cultivation of Morchella US Patent 6,907,691Google Scholar
- Ower R, Mills GL, Malachowski JA(1986) Cultivation of Morchella. US patent 4594809Google Scholar
- Pagliaccia D, Douhan GW, Douhan LA, Peever TL, Carris LM, Kerrigan JL (2011) Development of molecular markers and preliminary investigation of the population structure and mating system in one lineage of black morel (Morchella elata) in the Pacific northwestern USA. Mycologia 103:969–982CrossRefPubMedGoogle Scholar
- Peng WH, Tang J, He XL, Chen Y, Tang H (2016) Status analysis of artificial cultivation of Morchella in Sichuan(Chinese). Edible Med Mush 24:145–150Google Scholar
- Pilz D, McLain R, Alexander S, Villarreal-Ruiz Berch S, Wurtz TL, Parks CG, McFarlane E, Baker B, Molina R, Smith JE (2007) Ecology and Management of Morels Harvested from the Forests of Western North America. Gen Tech Rep PNW-GTR-710. U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, PortlandGoogle Scholar
- Richard F, Bellanger JM, Clowez P, Hansen K, O’Donnell K, Urban A, Sauve M, Courtecuisse R, Moreau PA (2015) True morels (Morchella, Pezizales) of Europe and North America: evolutionary relationships inferred from multilocus data and a unified taxonomy. Mycologia 107:359–382CrossRefPubMedGoogle Scholar
- Shear CL, Dodge BO (1927) Life histories and heterothallism of the red bread mould fungi of the Monillia sitipholia group. J Agric Res 34:1019–1042Google Scholar