Abstract - Khalouf

IRT1 is the major Fe2+ transporter in Arabidopsis roots, localized to the plasma membrane, exhibiting a high affinity towards Fe2+, and serving as the main player in the regulation of plant iron homeostasis (Vert, 2002). IRT1 belongs to the ZIP protein family, whose members share a similar topology (Guerinot, 2000) and many of them are dimers on the cell membrane (Ahern, 2019; Chun, 2019), IRT1 is regulated at various levels that favor optimal iron acquisition, such as the rapid transcriptional induction of IRT1 following iron deficiency (Connolly, 2002), and post-translational regulation through degradation and turnover of IRT1 (Kerkeb, 2008). Since dimerization can have roles in zinc transport in some ZIP proteins (Zhang, 2016), a question has arisen for us about the oligomerization state of IRT1 which wasn’t studied before and which could also play a role in iron uptake and regulations. In our group, we investigate the regulation, mobility, and oligomerization state of IRT1 at the molecular level. To isolate these processes from other cellular interactions occurring in plants, we established a synthetic system in which IRT1 was expressed with fluorescent protein tags. FRAP and FRET-APB were then detected to analyse its mobility and oligomerization state.

Hadeel Khalouf1, Inga Mohr1, Paulina Blair1, Cornelia Monzel1, and Petra Bauer1. (1 Heinrich Heine University, Düsseldorf, Germany)