Research On The Signal Pathway Of Arabidopsis Protein RIN13

NLRs(Nucleotide-binding / Leucine-rich Repeat Receptors)function as plant immunity receptors to mediate effector-triggered immunity(ETI),which confers local programmed cell death to inhibit further spread of pathogenic bacteria in the plant.As an RPM1(Resistance to P.Syringae pv Maculicoala 1)interaction protein,RIN13(RPM1 Interacting Protein 13)can enhance plant disease resistance and inhibit the hypersensitive response(HR).Overexpression of RIN13 in Arabidopsis(OE-RIN13)induces dwarfism of the plant,enhanced disease resistance,high salicylic acid(SA)level and the up-regulation of the genes mediated by SA signaling.Overexpression of RIN13 causes stomatal closure,which results in enhancing the plant disease resistance.Nevertheless,the resistance mechanisms of RIN13,causing stomatal closure and upregulation of SA still elusive.In this research,through yeast two-hybrid system,we found two candidates of RIN13 interacting proteins: ARF1(Auxin Response Factor 1)and ARIA(Arm Repeat Protein Interacting with ABF2),which involved in the auxin and abscisic acid signaling pathway respectively.RIN13 cannot interact with other ARFs family protein in Y2 H assay but can affect the transcriptional ability of the ARFs family proteins.RIN13 affects the nuclear localization of ARF1 and ARF2,and can interact with ARF5 and result in the degradation of ARF5 protein.There are complex interactions between ARFs family proteins,RIN13 may interact with some ARFs proteins and then affects the transcriptional function of other ARFs family members indirectly.Since RIN13 induces the stomatal closure,we crossed ost1 or slac1 knock-out mutant with OE-RIN13 and found that ost1 rescued RIN13-induced dwarf phenotype,suggesting OST1 participates RIN13 signal transduction.