7TNS
Subpellicular microtubule from detergent-extract Toxoplasma gondii cells
This is a non-PDB format compatible entry.
Summary for 7TNS
| Entry DOI | 10.2210/pdb7tns/pdb |
| EMDB information | 26018 26019 |
| Descriptor | Microtubule associated protein SPM1, Tubulin alpha chain, Tubulin beta chain, ... (5 entities in total) |
| Functional Keywords | parasites, toxoplasma gondii, cytoskeleton, microtubules, tubulin, cell invasion |
| Biological source | Toxoplasma gondii More |
| Total number of polymer chains | 101 |
| Total formula weight | 4159286.59 |
| Authors | Sun, S.Y.,Pintilie, G.D.,Chen, M.,Chiu, W. (deposition date: 2022-01-21, release date: 2022-06-22, Last modification date: 2024-11-06) |
| Primary citation | Sun, S.Y.,Segev-Zarko, L.A.,Chen, M.,Pintilie, G.D.,Schmid, M.F.,Ludtke, S.J.,Boothroyd, J.C.,Chiu, W. Cryo-ET of Toxoplasma parasites gives subnanometer insight into tubulin-based structures. Proc.Natl.Acad.Sci.USA, 119:-, 2022 Cited by PubMed Abstract: Tubulin is a conserved protein that polymerizes into different forms of filamentous structures in , an obligate intracellular parasite in the phylum Apicomplexa. Two key tubulin-containing cytoskeletal components are subpellicular microtubules (SPMTs) and conoid fibrils (CFs). The SPMTs help maintain shape and gliding motility, while the CFs are implicated in invasion. Here, we use cryogenic electron tomography to determine the molecular structures of the SPMTs and CFs in vitrified intact and detergent-extracted parasites. Subvolume densities from detergent-extracted parasites yielded averaged density maps at subnanometer resolutions, and these were related back to their architecture in situ. An intralumenal spiral lines the interior of the 13-protofilament SPMTs, revealing a preferred orientation of these microtubules relative to the parasite's long axis. Each CF is composed of nine tubulin protofilaments that display a comma-shaped cross-section, plus additional associated components. Conoid protrusion, a crucial step in invasion, is associated with an altered pitch of each CF. The use of basic building blocks of protofilaments and different accessory proteins in one organism illustrates the versatility of tubulin to form two distinct types of assemblies, SPMTs and CFs. PubMed: 35121661DOI: 10.1073/pnas.2111661119 PDB entries with the same primary citation |
| Experimental method | ELECTRON MICROSCOPY (6.7 Å) |
Structure validation
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