Cao Zhi, Chen Hongyu, Zhou Chenli, Gong Ming, Li Yan, Shao Youran, Wu Yingying, Bao Dapeng
School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China.
National Engineering Research Center of Edible Fungi, Key Laboratory of Applied Mycological Resources and Utilization of Ministry of Agriculture, Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai 201403, China.
Metabolites. 2024 Jan 27;14(2):94. doi: 10.3390/metabo14020094.
γ-Aminobutyric (GABA) acid is a nutrient and signaling molecule existing in many plants, participating in the regulation of metabolism and various physiological activities. Two strains of (a white variety and a brown variety) were investigated to study the impact of exogenous GABA on mycelial growth and the response to stress. Mycelial growth, microscopic morphology, antioxidant profile, and expression in were investigated under salt, dehydration, or cold stress. The results indicated that 5 mM GABA stimulated mycelial growth under standard cultivation conditions, whereas GABA addition over 10 mM hindered the growth. Under salt, dehydration, or cold stress, treatment with 5 mM GABA significantly enhanced the mycelial growth rate and density of both strains by promoting front hyphae branching. Meanwhile, the activities of key antioxidant enzymes such as peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) were enhanced by GABA, thereby augmenting the defensive network against abiotic stress. Additionally, expression and GABA concentration were increased under abiotic stresses as a resistance regulation response. The exogenous addition of GABA strengthened the upregulation of expression and GABA production. These findings indicated that exogenously adding low concentrations of GABA effectively enhanced the mycelial growth and antioxidant profile of , thereby improving its resistance against stresses.
γ-氨基丁酸（GABA）是一种存在于许多植物中的营养和信号分子，参与新陈代谢和各种生理活动的调节。研究了两株（一个白色品种和一个棕色品种）以研究外源GABA对菌丝体生长的影响以及对应激的反应。在盐、脱水或冷胁迫下，研究了菌丝体生长、微观形态、抗氧化特征以及中的表达。结果表明，在标准培养条件下，5 mM GABA刺激菌丝体生长，而添加超过10 mM的GABA则会阻碍生长。在盐、脱水或冷胁迫下，用5 mM GABA处理通过促进前沿菌丝分支显著提高了两株菌株的菌丝体生长速率和密度。同时，GABA增强了过氧化物酶（POD）、过氧化氢酶（CAT）和抗坏血酸过氧化物酶（APX）等关键抗氧化酶的活性，从而增强了抵御非生物胁迫的防御网络。此外，在非生物胁迫下，表达和GABA浓度作为抗性调节反应而增加。外源添加GABA增强了表达和GABA产生的上调。这些发现表明，外源添加低浓度的GABA有效地增强了的菌丝体生长和抗氧化特征，从而提高了其对胁迫的抗性。
