T3SS in Pseudomonas syringae and the regulatory mechanism:a review

Abstract:

The Gram-negative Pseudomonas syringae causes diverse plant diseases. It injects effector proteins into host cells via type III secretion system (T3SS), thereby suppressing the immune system of the host and colonizing the host. RhpR/S, the main regulator of T3SS, directly regulates hrpR/S and other virulence-related pathways in response to changes in environmental signals. The expression of the T3SS genes is also affected by other regulatory factors, including sigma factor HrpL, two-component system GacA/S, Lon protease, second messenger molecules, and environmental signals. This paper aims to brief the composition and functions of T3SS in P. syringae and review the regulatory mechanism of T3SS in the bacterial species, which is expected to serve as a reference for in-depth research on the pathogenic mechanisms of P. syringae.