7YTJ

Cryo-EM structure of VTC complex

Summary for 7YTJ

• Entry DOI: 10.2210/pdb7ytj/pdb
• EMDB information: 34090
• Descriptor: Vacuolar transporter chaperone 4, Vacuolar transporter chaperone 1, Vacuolar transporter chaperone 3, ... (6 entities in total)
• Functional Keywords: vtc complex, poly p., transport protein
• Biological source: Saccharomyces cerevisiae (baker's yeast); More
• Total number of polymer chains: 5
• Total formula weight: 238128.20

Authors

Guan, Z.Y.,Chen, J.,Liu, R.W.,Chen, Y.K.,Xing, Q.,Du, Z.M.,Liu, Z. (deposition date: 2022-08-15, release date: 2023-02-22, Last modification date: 2025-07-02)

Primary citation

Guan, Z.,Chen, J.,Liu, R.,Chen, Y.,Xing, Q.,Du, Z.,Cheng, M.,Hu, J.,Zhang, W.,Mei, W.,Wan, B.,Wang, Q.,Zhang, J.,Cheng, P.,Cai, H.,Cao, J.,Zhang, D.,Yan, J.,Yin, P.,Hothorn, M.,Liu, Z.
The cytoplasmic synthesis and coupled membrane translocation of eukaryotic polyphosphate by signal-activated VTC complex.
Nat Commun, 14:718-718, 2023

PubMed Abstract: Inorganic polyphosphate (polyP) is an ancient energy metabolite and phosphate store that occurs ubiquitously in all organisms. The vacuolar transporter chaperone (VTC) complex integrates cytosolic polyP synthesis from ATP and polyP membrane translocation into the vacuolar lumen. In yeast and in other eukaryotes, polyP synthesis is regulated by inositol pyrophosphate (PP-InsP) nutrient messengers, directly sensed by the VTC complex. Here, we report the cryo-electron microscopy structure of signal-activated VTC complex at 3.0 Å resolution. Baker's yeast VTC subunits Vtc1, Vtc3, and Vtc4 assemble into a 3:1:1 complex. Fifteen trans-membrane helices form a novel membrane channel enabling the transport of newly synthesized polyP into the vacuolar lumen. PP-InsP binding orients the catalytic polymerase domain at the entrance of the trans-membrane channel, both activating the enzyme and coupling polyP synthesis and membrane translocation. Together with biochemical and cellular studies, our work provides mechanistic insights into the biogenesis of an ancient energy metabolite.

PubMed: 36759618
DOI: 10.1038/s41467-023-36466-4

Experimental method

ELECTRON MICROSCOPY (3 Å)