AtsPLA2-α nuclear relocalization by the Arabidopsis transcription factor AtMYB30 leads to repression of the plant defense response
Solène Froidure, Joanne Canonne, Xavier Daniela, Alain Jauneau, Christian Brière, Dominique Roby, and Susana Rivas
Résumé:
The hypersensitive response (HR), characterized by a rapid and localized cell death at the inoculation site, is one of the most efficient resistance reactions to pathogen attack in plants. The transcription factor AtMYB30 was identified as a positive regulator of the HR and resistance responses during interactions between Arabidopsis and bacteria. Here, we show that AtMYB30 and the secreted phospholipase AtsPLA2-α physically interact in vivo, following the AtMYB30-mediated specific relocalization of AtsPLA2-α from cytoplasmic vesicles to the plant cell nucleus. This protein interaction leads to repression of AtMYB30 transcriptional activity and negative regulation of plant HR. Moreover, Atspla2-α mutant plants are more resistant to bacterial inoculation, whereas AtsPLA2-α overexpression leads to decreased resistance, confirming that AtsPLA2-α is a negative regulator of AtMYB30-mediated defense. These data underline the importance of cellular dynamics and, particularly, protein translocation to the nucleus, for defense-associated gene regulation in plants.
Revue:
PNAS
Lien:
https://www.pnas.org/content/107/34/15281.short