Find in Library

Transcription activator-like effectors (TALEs) play a significant role for pathogenesis in several xanthomonad pathosystems. <i>Xanthomonas phaseoli</i> pv. <i>manihotis</i> (<i>Xpm</i>), the causal agent of Cassava Bacterial Blight (CBB), uses TALEs to manipulate host metabolism. Information about <i>Xpm</i> TALEs and their target genes in cassava is scarce, but has been growing in the last few years. We aimed to characterize the TALE diversity in Colombian strains of <i>Xpm</i> and to screen for TALE-targeted gene candidates. We selected eighteen <i>Xpm</i> strains based on neutral genetic diversity at a country scale to depict the TALE diversity among isolates from cassava productive regions. RFLP analysis showed that <i>Xpm</i> strains carry TALomes with a bimodal size distribution, and affinity-based clustering of the sequenced TALEs condensed this variability mainly into five clusters. We report on the identification of 13 novel variants of TALEs in <i>Xpm</i>, as well as a functional variant with 22 repeats that activates the susceptibility gene <i>MeSWEET10a</i>, a previously reported target of TAL20<i>_Xam668</i>. Transcriptomics and EBE prediction analyses resulted in the selection of several TALE-targeted candidate genes and two potential cases of functional convergence. This study provides new bases for assessing novel potential TALE targets in the <i>Xpm–</i>cassava interaction, which could be important factors that define the fate of the infection.