title: Riboflavin level manipulates the successive developmental sequences in Aspergillus nidulans.
abstract: Auxotrophic markers are useful in fungal genetic analysis. Among the auxotrophic markers, riboB2 is one of the most commonly used markers in many laboratory strains. However, riboB2 mutants in Aspergillus nidulans confer self-sterility and thus are unable to form hybrid cleistothecia by outcross when both parent strains harbor riboB2 auxotrophic marker under the standard protocol. To assess the role of riboflavin during the different developmental stages of A. nidulans, the limited concentrations of riboflavin were monitored. The commonly used dosage of riboflavin (2.5 µg/ml) in the standard medium recipe is enough for hyphal growth and conidiation in the riboflavin auxotrophic riboB2 mutants (enough at 0.02 and 0.5 μg/ml, respectively) in A. nidulans. However, the dosage is not enough to support mature cleistothecium formation. Furthermore, the self-sterile defects in riboB2 mutants on standard medium could be restored by the addition of 25 μg/ml riboflavin, although the required riboflavin concentrations are varied in different genotype strains in A. nidulans. Most importantly, the outcross between riboB2 mutants could also be achieved by the supply of riboflavin in the sexual developmental stage. Our results highlight the potential roles of auxotrophic markers in the development of fungi and improve the efficiency of the genetic analysis in A. nidulans.
authors.affiliation: Jiangsu Key Laboratory for Microbes and Functional Genomics, Engineering and Technology Research Center for Microbiology, College of Life Sciences, Nanjing Normal University, No. 1 Wen Yuan Rd, Qi Xia Qu, Nanjing, 210046, Jiangsu, China, 664661595@qq.com.
authors.forename: Hailin
authors.initials: H
authors.lastname: Zheng
authors.forename: Shenghua
authors.initials: S
authors.lastname: Zhang
authors.forename: Shizhu
authors.initials: S
authors.lastname: Zhang
authors.forename: Ling
authors.initials: L
authors.lastname: Lu
mesh_terms: D001233:Aspergillus nidulans / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D003433:Crosses, Genetic; D003470:Culture Media / Q000737:chemistry; D025301:Hyphae / Q000187:drug effects / Q000254:growth & development; D012256:Riboflavin / Q000378:metabolism*; D013172:Spores, Fungal / Q000187:drug effects / Q000254:growth & development
chemical_list: D003470:Culture Media; D012256:Riboflavin