8X2U

Radial spoke head-neck dimer

Summary for 8X2U

• Entry DOI: 10.2210/pdb8x2u/pdb
• EMDB information: 38020
• Descriptor: DPY30 domain containing 2, DnaJ homolog subfamily B member 13, Radial spoke head protein 3 homolog B, ... (7 entities in total)
• Functional Keywords: radial spoke, cilia, structural protein
• Biological source: Mus musculus (house mouse); More
• Total number of polymer chains: 20
• Total formula weight: 846964.19

Authors

Meng, X.,Cong, Y. (deposition date: 2023-11-10, release date: 2024-02-07)

Primary citation

Meng, X.,Xu, C.,Li, J.,Qiu, B.,Luo, J.,Hong, Q.,Tong, Y.,Fang, C.,Feng, Y.,Ma, R.,Shi, X.,Lin, C.,Pan, C.,Zhu, X.,Yan, X.,Cong, Y.
Multi-scale structures of the mammalian radial spoke and divergence of axonemal complexes in ependymal cilia.
Nat Commun, 15:362-362, 2024

PubMed Abstract: Radial spokes (RS) transmit mechanochemical signals between the central pair (CP) and axonemal dynein arms to coordinate ciliary motility. Atomic-resolution structures of metazoan RS and structures of axonemal complexes in ependymal cilia, whose rhythmic beating drives the circulation of cerebrospinal fluid, however, remain obscure. Here, we present near-atomic resolution cryo-EM structures of mouse RS head-neck complex in both monomer and dimer forms and reveal the intrinsic flexibility of the dimer. We also map the genetic mutations related to primary ciliary dyskinesia and asthenospermia on the head-neck complex. Moreover, we present the cryo-ET and sub-tomogram averaging map of mouse ependymal cilia and build the models for RS1-3, IDAs, and N-DRC. Contrary to the conserved RS structure, our cryo-ET map reveals the lack of IDA-b/c/e and the absence of Tektin filaments within the A-tubule of doublet microtubules in ependymal cilia compared with mammalian respiratory cilia and sperm flagella, further exemplifying the structural diversity of mammalian motile cilia. Our findings shed light on the stepwise mammalian RS assembly mechanism, the coordinated rigid and elastic RS-CP interaction modes beneficial for the regulation of asymmetric ciliary beating, and also facilitate understanding on the etiology of ciliary dyskinesia-related ciliopathies and on the ependymal cilia in the development of hydrocephalus.

PubMed: 38191553
DOI: 10.1038/s41467-023-44577-1

Experimental method

ELECTRON MICROSCOPY (3.57 Å)