Phosphorylation of syndapin I F-BAR domain at two helix-capping motifs regulates membrane tubulation
Annie Quana, Jing Xue, Jerome Wielens, Karen J Smillie, Victor Anggono, Michael W Parker, Michael A Cousin, Mark E Graham, Phillip J Robinson
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA | NATL ACAD SCIENCES | Published : 2012
Syndapin I (PACSIN 1) is a synaptically enriched membrane tubulating protein that plays important roles in activity-dependent bulk endocytosis and neuronal morphogenesis. While syndapin I is an in vitro phosphoprotein, it is not known to be phosphorylated in neurons. Here, we report the identification of two phosphorylation sites, S76 and T181, of syndapin I from nerve terminals. Both residues are located at the N-terminal helix-capping motifs (N-Cap) of different α-helices in the F-BAR domain, important for F-BAR homodimer curvature and dimer-dimer filament assembly, respectively. Phospho-mimetic mutations of these residues regulate lipid-binding and tubulation both in vitro and in cells. N..View full abstract
We wish to thank our colleagues at the Children's Medical Research Institute (CMRI) for providing reagents and technical assistance. This work is supported by grants from the Australian National Health and Medical Research Council, the Ramaciotti Foundation, Cancer Institute N.S.W., and the Ian Potter Foundation. A. Q. is supported by a CMRI postgraduate research scholarship.