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Chromosomal genome sequence assembly and mating-type (MAT) locus characterization of the leprose asexual lichenized fungus Lepraria neglecta (Nyl.) Erichsen

Published online by Cambridge University Press:  15 March 2023

Bubba Pfeffer
Department of Biology, Eastern Washington University, Cheney, WA, USA
Chandler Lymbery
Department of Biology, Eastern Washington University, Cheney, WA, USA
Brendan Booth
Department of Biology, Eastern Washington University, Cheney, WA, USA
Jessica L. Allen*
Department of Biology, Eastern Washington University, Cheney, WA, USA
Author for correspondence: Jessica L. Allen. E-mail:


Complete chromosomal-level assemblies of fungal genomes are rare. The intimate ecological symbioses and complex reproduction strategies utilized by fungi make highly contiguous, gapless genome assemblies particularly difficult. Here, we use long-read sequencing on the Oxford Nanopore Technology MinION platform to sequence and assemble the genome of Lepraria neglecta (Ascomycota, Lecanorales). In addition to eight contigs ascribable to chromosomes, six of which are assembled telomere-to-telomere, we discovered the presence of a complete MAT locus with two conserved MAT1-2 genes and a putative MAT1-1 pseudogene. The full genome assembly of a widespread, common species presents an opportunity for new insights into lichen reproduction while the presence of the mating-type locus in the genome of an asexual lichen raises fundamental questions about reproductive biology in fungi generally.

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Copyright © The Author(s), 2023. Published by Cambridge University Press on behalf of the British Lichen Society

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