Histidine kinase is a type of sensor kinase widely found in bacteria, fungi, and plants, crucial for two-component signaling systems, monitoring environmental changes through phosphorylation reactions. Composed of a sensing domain and a transmitter domain, they are typically located on the cell membrane, activating response regulators through phosphorylation of their own histidine residue upon sensing external signals. The gene expression of histidine kinase is tissue and environment-specific, essential for biological processes such as environmental adaptation, pathogen defense, and biomembrane transmission. Mutations or dysregulation in their genes can lead to abnormal signal transduction pathways, affecting the growth and disease resistance of the organism.