The γ-aminobutyric acid (GABA) is a widely distributed neurotransmitter in living organisms, known for its inhibitory role in animals. GABA exerts calming effects on the mind, lowers blood pressure in animals, and enhances stress resistance during the growth and development of plants. Enhancing GABA content in plants has become a focal point of current research. In plants, GABA is synthesized through two metabolic pathways, the GABA shunt and the polyamine degradation pathway, with the GABA shunt being the primary route. Extensive studies have investigated the regulatory mechanisms governing GABA synthesis. At the genetic level, GABA production and degradation can be modulated by gene overexpression, signaling molecule-induced expression, transcription factor regulation, and RNA interference. Additionally, at the level of transporter proteins, increased activity of GABA transporters and proline transporters enhances the transport of glutamate and GABA. The activity of glutamate decarboxylase, a key enzyme in GABA synthesis, along with various external factors, also influences GABA synthesis. This paper summarizes the biological functions, metabolic pathways, and regulatory mechanisms of GABA, providing a theoretical foundation for further research on GABA in plants.

β-glucan is an important component of crop cell walls, and its chemical structure is closely related to its physiological function. Among them, (1,3;1,4)-β-glucan (mixed-linkage β-glucan, MLGs) is a unique type of β-glucan in graminaceous crops. In recent years, the identification and functional analysis of the β-glucan synthesis gene family have provided key molecular targets for quality improvement of crops. This review systematically examines the classification, structure, and function of the β-glucan synthetic gene family, focusing on the regulatory network. This will lay a theoretical foundation for the further improvement of the β-glucan content in crops.