Cloning and functional analysis of two type III-secreted effectors in Pseudomonas syringae pv. glycinea

Abstract:

For studying the pathogenesis of the soybean pathogen Pseudomonas syringae pv. glycinea, two types of homologous genes of III-secreted effectors, named as HopAB1s and HopAF1s respectively, were first cloned from Pseudomonas syringae pv. glycinea by means of inverse PCR (iPCR) method. The ORF of HopAB1s gene contained 1 572 bp, encoding 523 amino acid residues. The ORF of HopAF1s gene contained 855 bp, encoding 283 amino acid residues. The two genes registered in GenBank with accession numbers JF826562 and JF826563. The N-terminus of HopAB1s was sufficient for E3 ubiquitin ligases functional domain. The two effectors were inserted into the binary PVX vector, trans-formed into Agrobactrium tumefaciens GV3101, and the Agrobacterium-mediated transient expression experiments confirmed that two effectors functioned to inhibit the ability of the pro-apoptotic protein Bax inducing PCD in plant. Furthermore, infection experiment results showed that the effectors can promote ability of Phylophthora nicotianae infecting tobacco (Nicotiana benthamiana). Two cloned genes both belong to suppressive effector, our research is lay a foundation for revealed the molecular pathogenesis of Pseudomonas syringae pv. glycinea.