Fig. 7

A working model for TIRP1 regulating self-association, autoactivity, and VW resistance of dual-TIR domain protein in the plant. Under normal growth conditions, the constitutive expression of TIRP1 mediates accumulation of sufficient protein to competitively bind to TIR1-TIR2, thus inhibiting their self-association, and subsequent immune response mediated by GhRVD1. The downregulation of TIRP1 expression after V. dahliae invasion releases the TIRP1 from TIR1-TIR2 domain of GhRVD1 and indirectly leads to increased TIR1-TIR2 self-association. Furthermore, increasing dimer of TIR1-TIR2 contributes to activate the transcription of hypersensitive response-related gene HSR203J/HIN1 and systemic acquired resistance-related gene NPR1/PR1, thus enhancing cotton resistance against V. dahliae. The width of the arrows indicates the strength of the downstream signaling. Blue circles represent molecules associated with V. dahliae infection