8cx6

TPX2 Minimal Active Domain on MicrotubulesTPX2 Minimal Active Domain on Microtubules

Structural highlights 8cx6 is a 1 chain structure with sequence from Xenopus laevis. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: Solid-state NMR Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function TPX2A_XENLA Spindle assembly factor. Required for normal assembly of mitotic spindles. Mediates the binding kif15 and aurka to spindle microtubules. Required for targeting kif15 to microtubule minus ends. Activates aurka by promoting its autophosphorylation and protects the phosphorylated residue against dephosphorylation (By similarity). Publication Abstract from PubMed Targeting protein for Xklp2 (TPX2) is a key factor that stimulates branching microtubule nucleation during cell division. Upon binding to microtubules (MTs), TPX2 forms condensates via liquid-liquid phase separation, which facilitates recruitment of microtubule nucleation factors and tubulin. We report the structure of the TPX2 C-terminal minimal active domain (TPX2(alpha5-alpha7)) on the microtubule lattice determined by magic-angle-spinning NMR. We demonstrate that TPX2(alpha5-alpha7) forms a co-condensate with soluble tubulin on microtubules and binds to MTs between two adjacent protofilaments and at the intersection of four tubulin heterodimers. These interactions stabilize the microtubules and promote the recruitment of tubulin. Our results reveal that TPX2(alpha5-alpha7) is disordered in solution and adopts a folded structure on MTs, indicating that TPX2(alpha5-alpha7) undergoes structural changes from unfolded to folded states upon binding to microtubules. The aromatic residues form dense interactions in the core, which stabilize folding of TPX2(alpha5-alpha7) on microtubules. This work informs on how the phase-separated TPX2(alpha5-alpha7) behaves on microtubules and represents an atomic-level structural characterization of a protein that is involved in a condensate on cytoskeletal filaments. Structural basis of protein condensation on microtubules underlying branching microtubule nucleation.,Guo C, Alfaro-Aco R, Zhang C, Russell RW, Petry S, Polenova T Nat Commun. 2023 Jun 21;14(1):3682. doi: 10.1038/s41467-023-39176-z. PMID:37344496 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

spinqualitylabelsall models 8cx6 Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image