8I7O

In situ structure of axonemal doublet microtubules in mouse sperm with 16-nm repeat

This is a non-PDB format compatible entry.

Summary for 8I7O

• Entry DOI: 10.2210/pdb8i7o/pdb
• EMDB information: 35210 35211 35229
• Descriptor: Tektin-1, EF-hand domain-containing family member C2, Protein FAM166A, ... (25 entities in total)
• Functional Keywords: microtubules, axoneme, sperm, filament, structural protein
• Biological source: Mus musculus (house mouse); More
• Total number of polymer chains: 189
• Total formula weight: 9097620.20

Authors

Zhu, Y.,Yin, G.L.,Tai, L.H.,Sun, F. (deposition date: 2023-02-01, release date: 2023-10-11, Last modification date: 2025-09-17)

Primary citation

Tai, L.,Yin, G.,Huang, X.,Sun, F.,Zhu, Y.
In-cell structural insight into the stability of sperm microtubule doublet.
Cell Discov, 9:116-116, 2023

PubMed Abstract: The propulsion for mammalian sperm swimming is generated by flagella beating. Microtubule doublets (DMTs) along with microtubule inner proteins (MIPs) are essential structural blocks of flagella. However, the intricate molecular architecture of intact sperm DMT remains elusive. Here, by in situ cryo-electron tomography, we solved the in-cell structure of mouse sperm DMT at 4.5-7.5 Å resolutions, and built its model with 36 kinds of MIPs in 48 nm periodicity. We identified multiple copies of Tektin5 that reinforce Tektin bundle, and multiple MIPs with different periodicities that anchor the Tektin bundle to tubulin wall. This architecture contributes to a superior stability of A-tubule than B-tubule of DMT, which was revealed by structural comparison of DMTs from the intact and deformed axonemes. Our work provides an overall molecular picture of intact sperm DMT in 48 nm periodicity that is essential to understand the molecular mechanism of sperm motility as well as the related ciliopathies.

PubMed: 37989994
DOI: 10.1038/s41421-023-00606-3

Experimental method

ELECTRON MICROSCOPY (4.5 Å)