Citrus MAF1, a Repressor of RNA Polymerase III, Binds the Xanthomonas citri Canker Elicitor PthA4 and Suppresses Citrus Canker Development

摘要: Transcription activator-like (TAL) effectors from Xanthomonas species pathogens act as transcription factors in plant cells; however, how TAL activate host is unknown. We found previously that of the citrus canker pathogen citri, known PthAs, bind carboxyl-terminal domain sweet orange (Citrus sinensis) RNA polymerase II (Pol II) and inhibit activity CsCYP, a cyclophilin associated with Pol functions negative regulator cell growth. Here, we show PthA4 specifically interacted MAF1 (CsMAF1) protein, an III III) repressor controls ribosome biogenesis growth yeast (Saccharomyces cerevisiae) human. CsMAF1 bound human rescued maf1 mutant by repressing tRNAHis transcription. The expression slightly restored synthesis, indicating counteracts activity. In addition, interference plants reduced levels displayed dramatic increase tRNA marked phenotype proliferation during formation. Conversely, overexpression was detrimental to seedling growth, inhibited attenuated development. Furthermore, required elicit cankers leaves depletion X. citri-infected tissues correlates development hyperplastic lesions presence PthA4. Considering CsCYP function suppressors orange, our data indicate citri target regulators coordinately genes involved proliferation.