Escherichia coli mazEF Toxin-Antitoxin System asa Tool to Target Cell Ablation in Plants

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Résumé

Background/Aims: The Escherichia coli MazF is an endoribonuclease that cleaves mRNA at ACA sequences, thereby triggering inhibition of protein synthesis. The aim of this study
is to evaluate the efficiency of the mazEF toxin-antitoxin system in plants to develop biotechnological tools for targeted cell ablation. Methods: A double transformation strategy, combining expression of the mazE antitoxin gene under the control of the CaMV 35S promoter, reported to drive expression in all plant cells except within the tapetum, together
with the expression of the mazF gene under the control of the TA29 tapetum-specific promoter in transgenic tobacco, was applied. Results: No transgenic TA29-mazF line could be
regenerated, suggesting that the TA29 promoter is not strictly tapetum specific and that MazF is toxic for plant cells.The regenerated 35S-mazE/TA29-mazF double-transformed lines gave a unique phenotype where the tapetal cell layer

Mots-clés

Toxin-antitoxin system, MazF endoribonuclease, Escherichia coli, Nicotiana tabacum, Tapetum, Targeted cell ablation