Research progress in the application of detection techniques for plant protein phosphorylation

In plant signal transduction, protein phosphorylation is an essential posttranslational modification that plays a vital role in various aspects of plant life, including growth, development, and response to environmental stresses. During plant growth and development, from seed germination to mature organ formation, protein phosphorylation acts as a master regulator controlling the activity of key proteins involved in cell division, differentiation, and expansion. Additionally, plants encounter stresses such as drought, high salinity, extreme temperatures, and pathogen attack. Protein phosphorylation quickly triggers stress-responsive signaling cascades in response to these conditions, activating stress-related gene expression, regulating the synthesis of osmoprotectants to preserve cellular water balance, and modulating antioxidant enzyme activity to scavenge reactive oxygen species produced under heightened stress. Therefore, protein phosphorylation is vital for plant adaptation and survival in harsh environments.

In recent years, as interest in understanding the molecular basis of plant biology has grown, numerous methods have been used to detect dynamic changes in protein phosphorylation and explore its functional mechanisms. These methods range from traditional biochemical techniques to advanced high-throughput technologies, each offering unique advantages for studying protein phosphorylation. This review provides a comprehensive summary of the diverse methods employed in researching plant protein phosphorylation signaling networks, along with recent advancements. First, an overview of the process, types, and classification of protein phosphorylation is presented. Protein phosphorylation involves the transfer of a phosphate group from a donor molecule, typically ATP, to specific amino acid residues on target proteins via protein kinases. The main types include serine, threonine, and tyrosine phosphorylation, each with distinct features and biological roles. Additionally, different amino acids can result in diverse phosphorylation forms. A classification system is also introduced, categorizing protein phosphorylation based on factors like the functional groups of target proteins and signaling pathways involved. Moreover, the methods for detecting protein phosphorylation are summarized in detail. Traditional techniques such as radioactive labeling, which tracks phosphate incorporation using radioactive isotopes, have been widely used but pose safety concerns and limit large-scale analysis. Modern approaches, including immunoblotting with phosphorylation-specific antibodies, enable specific detection of phosphorylated proteins through antigen-antibody interactions. High-throughput techniques like mass spectrometry-based phosphoproteomics have revolutionized the field, allowing large-scale identification and quantification of phosphorylated proteins within a single experiment, providing a global view of phosphorylation changes under different conditions. Finally, the progress in studying protein phosphorylation in plants is outlined, highlighting its roles in hormone signaling and resistance to salt, drought, cold, and disease stresses.

By summarizing recent key findings, this review offers a valuable reference for further investigation into plant protein phosphorylation. In the future, it may inspire new research directions and enhance our understanding of plant biology.