Auricularia heimuer is an important cultivated edible mushroom in China. This study used the early maturity, chrysanthemum-shaped, high yield strain “8808” and the late-maturity, single-shaped, high-quality strain “HW15” as parental strains. The objective was to develop a new strain of A. heimuer combining early maturity with excellent quality through protoplast fusion. Protoplasts from the parental strains were fused using a polyethylene glycol (PEG)-mediated method. The obtained hybrids were identified through clamp connection, antagonism tests, esterase isozyme analysis, and Inter-Simple Sequence Repeat (ISSR) molecular marker techniques, followed by ultimate selection through cultivation. Among the evaluated hybrids, strain R33 exhibited desirable agronomic traits: primordium formation occurred 4 days earlier than the parental strain HW15, harvest time was advanced by 6 days, yield increased by 14.7%, and the ratio of absorbed water improved by 29.8%. Transcriptomic analysis revealed that starch and sucrose metabolism as well as amino acid metabolism pathways were significantly upregulated in R33, which may be associated with its early maturity and high-yield phenotype. Overall, protoplast fusion technology can be used to create promising candidate strains that combine early maturity, high yield, and excellent quality.

This paper systematically reviews the research progress on the physiological functions, gene cloning, classification basis, and expression regulation mechanisms of laccase in edible and medicinal fungi. Laccase is a copper-containing polyphenol oxidase widely distributed in these fungi, characterized by broad-spectrum substrate catalytic activity and redox properties. It plays a central role in lignin degradation, pigment synthesis, and environmental pollutant treatment. Regarding gene cloning, researchers have successfully isolated and identified laccase genes from multiple species using techniques such as transcriptome sequencing, RACE amplification, and gene knockout. Expression regulation studies have revealed that laccase genes exhibit stage-specific expression patterns during mycelial growth, fruiting body development, and lignin degradation. In recent years, breakthroughs in genomics, transcriptomics, and gene editing technologies have greatly advanced research into the cloning, classification, and regulatory mechanisms of laccase genes. This article systematically reviews the diversity, clonal classification, and regulatory mechanisms of these genes, aiming to provide a reference for further research and industrial development of laccase in edible and medicinal fungi.