A plant pathogen type III effector protein subverts translational regulation to boost host polyamine levels Wu, D. S. von Roepenack-Lahaye, E. Buntru, M. de Lange, O. Schandry, N. Perez-Quintero, A. L. Weinberg, Z. Lowe-Power, T. M. /Szurek, Boris Michael, A. J. Allen, C. Schillberg, S. Lahaye, T. Pathogenic bacteria inject effector proteins into host cells to manipulate cellular processes and facilitate the infection. Transcription-activator-like effectors (TALEs), an effector class in plant pathogenic bacteria, transcriptionally activate host genes to promote disease. We identify arginine decarboxylase (ADC) genes as the host targets of Brg11, a TALE-like effector from the plant pathogen Ralstonia solanacearum. Brg11 targets a 17-bp sequence that was found to be part of a conserved 50-bp motif, termed the ADC-box, upstream of ADC genes involved in polyamine biosynthesis. The transcribed ADC-box attenuates translation from native ADC mRNAs; however, Brg11 induces truncated ADC mRNAs lacking the ADC-box, thus bypassing this translational control. As a result, Brg11 induces elevated polyamine levels that trigger a defense reaction and likely inhibits bacterial niche competitors but not R. solanacearum. Our findings suggest that Brg11 may give R. solanacearum a competitive advantage and uncover a role for bacterial effectors in regulating ternary microbe-host-microbe interactions. 2019 text https://www.documentation.ird.fr/hor/fdi:010077209 fdi:010077209 Wu D. S., von Roepenack-Lahaye E., Buntru M., de Lange O., Schandry N., Perez-Quintero A. L., Weinberg Z., Lowe-Power T. M., Szurek Boris, Michael A. J., Allen C., Schillberg S., Lahaye T.. A plant pathogen type III effector protein subverts translational regulation to boost host polyamine levels. 2019, 26 (5), 638-649+ 5 p. EN