Exploring PiTs: Functional and structural characterization of human SLC20 family members

• Applicant: Dr. Charlott Stock
• Subject Area: Structural Biology ; Biochemistry
• Term: from 2021 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 462647097

• Final Report Year: 2023

Final Report Abstract

The topic of this Walter Benjamin Postdoc fellowship conducted in the lab of Prof. Poul Nissen at Aarhus University were SLC20A1/2 or PiT1/2 which are rather enigmatic eukaryotic sodium-dependent phosphate transporters. They are ubiquitously expressed throughout the human body and were long described as housekeeping phosphate transporters. In recent years, both the discovery of an embryonic lethal phenotype of PiT1 KO in mice and the involvement of PiT1/2 in adapted and genetic calcification disorders brought these transporters into focus. The goal of this proposal was to foster understanding of the molecular mechanisms of PiT1/2 via functional and structural analysis. Unfortunately the results obtained during this fellowship were very limited. Although vigorously tried, protein production and purification to good quality and quantity could not be achieved. To allow further scientific development and diversification a second target protein was included towards the end of the study and enabled the planned short-term research stay in the lab of Markus Seeger / University of Zurich and training in and application of single-particle analysis in cryo-EM.

Publications

• Deciphering ion transport and ATPase coupling in the intersubunit tunnel of KdpFABC. Nature Communications, 12(1).
  Silberberg, Jakob M.; Corey, Robin A.; Hielkema, Lisa; Stock, Charlott; Stansfeld, Phillip J.; Paulino, Cristina & Hänelt, Inga
  
• Autoinhibition and regulation by phosphoinositides of ATP8B1, a human lipid flippase associated with intrahepatic cholestatic disorders. eLife, 11.
  Dieudonné, Thibaud; Herrera, Sara Abad; Laursen, Michelle Juknaviciute; Lejeune, Maylis; Stock, Charlott; Slimani, Kahina; Jaxel, Christine; Lyons, Joseph A.; Montigny, Cédric; Pomorski, Thomas Günther; Nissen, Poul & Lenoir, Guillaume
  
• Inhibited KdpFABC transitions into an E1 off-cycle state. eLife, 11.
  Silberberg, Jakob M.; Stock, Charlott; Hielkema, Lisa; Corey, Robin A.; Rheinberger, Jan; Wunnicke, Dorith; Dubach, Victor RA; Stansfeld, Phillip J.; Hänelt, Inga & Paulino, Cristina
  
• eGFP as an All-in-One Tag for Purification of Membrane Proteins. Methods in Molecular Biology, 171-186. Springer US.
  Heger, Tomáš; Stock, Charlott; Laursen, Michelle Juknaviciute; Habeck, Michael; Dieudonné, Thibaud & Nissen, Poul