Abstract: This paper reviewed the structures and DNA recognition mechanisms of the main DNA sensors in fish, including TLR9/TLR21, STING, cGAS, DDX41 and PKZ. These DNA sensors could detect the DNA of pathogenic microorganisms, and finally induced the expression of type I IFN and inflammatory factors through a series of signal transduction. In addition, this review analyzed the differences of DNA sensors between fish and mammals, and discussed the deficiencies in the current research of fish DNA sensors. It provided theoretical guidance for further study of fish DNA sensors.

Key words: fish, DNA sensors, signal pathway, innate immune