title: Identification of degenerate nuclei and development of a SCAR marker for Flammulina velutipes.
abstract: Flammulina velutipes is one of the major edible mushrooms in the world. Recently, abnormalities that have a negative impact on crop production have been reported in this mushroom. These symptoms include slow vegetative growth, a compact mycelial mat, and few or even no fruiting bodies. The morphologies and fruiting capabilities of monokaryons of wild-type and degenerate strains that arose through arthrospore formation were investigated through test crossing. Only one monokaryotic group of the degenerate strains and its hybrid strains showed abnormal phenotypes. Because the monokaryotic arthrospore has the same nucleus as the parent strain, these results indicated that only one aberrant nucleus of the two nuclei in the degenerate strain was responsible for the degeneracy. A sequence-characterized amplified region marker that is linked to the degenerate monokaryon was identified based on a polymorphic sequence that was generated using random primers. Comparative analyses revealed the presence of a degenerate-specific genomic region in a telomere, which arose via the transfer of a genomic fragment harboring a putative helicase gene. Our findings have narrowed down the potential molecular targets responsible for this phenotype for future studies and have provided a marker for the detection of degenerate strains.
authors.affiliation: Environment-friendly Research Division, Gyeongsangnam-do Agricultural Research and Extension Services, Jinju, Republic of Korea.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Environment-friendly Research Division, Gyeongsangnam-do Agricultural Research and Extension Services, Jinju, Republic of Korea.
authors.forename: Kyung-Hee
authors.initials: KH
authors.lastname: Kim
authors.affiliation: Environment-friendly Research Division, Gyeongsangnam-do Agricultural Research and Extension Services, Jinju, Republic of Korea.
authors.forename: Chak Han
authors.initials: CH
authors.lastname: Im
authors.affiliation: Environment-friendly Research Division, Gyeongsangnam-do Agricultural Research and Extension Services, Jinju, Republic of Korea.
authors.forename: Asjad
authors.initials: A
authors.lastname: Ali
authors.affiliation: Greenpeace Mushroom Co., Chungdo, Republic of Korea.
authors.forename: Chang Yun
authors.initials: CY
authors.lastname: Lee
authors.affiliation: Mushroom Research Division, National Institute of Horticultural and Herbal Science, Rural Development Administration, Eumsung, Republic of Korea.
authors.forename: Won-Sik
authors.initials: WS
authors.lastname: Kong
authors.affiliation: Environment-friendly Research Division, Gyeongsangnam-do Agricultural Research and Extension Services, Jinju, Republic of Korea.
authors.forename: Jae-San
authors.initials: JS
authors.lastname: Ryu
mesh_terms: D002467:Cell Nucleus / Q000378:metabolism*; D055393:Flammulina / Q000378:metabolism*; D016615:Telomere / Q000235:genetics