Variations in Nuclear Condition and Colony Morphology of Protoplast Regenerated Strains of Lentinula edodes

Variations in Nuclear Condition and Colony Morphology of Protoplast Regenerated Strains of Lentinula edodes

Eunjin Kim†, Mi-Jeong Park†, Yeongseon Jang*, and Kang-Hyeon Ka

Forest Microbiology Division, Department of Forest Bio-Resources, National Institute of Forest Science, Suwon, Republic of Korea

†Equal contributors
*Correspondence: idjys@korea.kr

Protoplast refers to the cell comprised of plasma membrane, cytosol, and cellular organelles except cell wall. In plants and fungi, protoplasts could be isolated by treatment of cell wall digestive enzymes. Protoplast technology for mushrooms has been mainly used for developing new strains by protoplast fusion and dedikaryotization. More recently, genetic transformation and genome editing have been the central aim of protoplast-based biotechnology in mushrooms. Although protoplast isolation and regeneration methods have been used for more than four decades, the characteristics of the protoplast regenerated strains (protoclones) have yet not been extensively studied. In this study, we examined the frequency of neohaplonts, the mycelial growth rate, and colony morphology of the protoclones obtained from two gill-less strains of Lentinula edodes. Even the protoclones originated from the same parental strain showed different growth rate and colony morphology, and the levels of variations in the characteristics of protoclones were strain-specific. The results imply that the protoplast isolation and regeneration process itself may affect the mycelial phenotypes and therefore the characteristics of the strain obtained by protoplast-based biotechnology should be carefully assessed.