Participation of the Arabidopsis thaliana PUT2 gene, encoding a polyamine transporter, in the plant defense response against Pseudomonas syringae

FLORES HERNÁNDEZ, E; GONZALEZ, ME; RODRÍGUEZ-KESSLER, M

Congreso; XIX National Plant Biochemistry and Molecular Biology Congress / XII Symposium Mexico-USA / 2nd ASPB Mexico Section; 2021

The interaction between plants and pathogens is very common in nature. For this reason, plants havedeveloped a highly regulated and complex defense system that is activated after pathogen recognition.The regulation of the plant defense system depends on several mediators, among which are polyamines.These polycationic aliphatic amines are present in all organisms, where they play essential functions forcell viability. In plants, polyamines participate in the establishment and regulation of the defense response,through changes in their metabolism (biosynthesis, conjugation-deconjugation, and catabolism), that resultin modifications of free and conjugated polyamines. However, it is unknown whether polyamine transporthas an implication in biotic stress response. In the present study, the importance of Polyamine UptakeTransport 2 (AtPUT2) in the interaction between Arabidopsis thaliana and Pseudomonas syringae pv.tomato DC3000 (Pst) was analyzed. Using a reporter promoter line (promAtPUT2::GUS) and analysis ofmRNA levels by qRT-PCR, it was found that AtPUT2 gene expression increased 6 hours post-inoculation(hpi) with Pst. In addition, the phenotype of a T-DNA insertional mutant line (Atput2-1) in response to Pstinfection was evaluated. A diminution in bacterial titers in the Atput2-1 mutant with respect to the wild-typeecotype was found 72 hpi. Furthermore, Atput2-1 mutant line had an increase in the expression levels ofthe PR-1 and ICS genes, two important markers of the salicylic acid pathway involved in plant response tobiotic stress. These results show that AtPUT2 is an interesting candidate to further evaluate the participationof polyamine transport in plant defense.