9V10

Cryo-EM structure of the 48-nm repeat doublet microtubule from mouse sperm

This is a non-PDB format compatible entry.

Summary for 9V10

• Entry DOI: 10.2210/pdb9v10/pdb
• EMDB information: 64623 64624 64625 64626 64679
• Descriptor: Cilia- and flagella-associated protein 95, Sperm axonemal maintenance protein CFAP97D1, Meiosis-specific nuclear structural protein 1, ... (64 entities in total)
• Functional Keywords: sperm flagellar doublet microtubules, structural protein
• Biological source: Mus musculus (house mouse); More
• Total number of polymer chains: 589
• Total formula weight: 27941667.98

Authors

Liu, Q.,Gui, M.,Wu, J.P.,Zhou, L.N. (deposition date: 2025-05-19, release date: 2026-05-27)

Primary citation

Liu, Q.,Zhou, L.,Liang, X.,Chen, P.,Li, B.,Yang, S.,Liu, Y.,Zhao, H.,Hu, J.,Feng, S.,Xie, S.,Wu, J.,Gui, M.
Doublet microtubule-associated tektins and enzymes differentially regulate sperm flagellar integrity and motility.
Nat Commun, 17:-, 2026

PubMed Abstract: Doublet microtubule (DMT)-associated proteins assemble and drive sperm flagella, which are essential for successful fertilization. However, the exact roles of different DMT-associated proteins in sperm function and the underlying molecular mechanisms remain elusive. Here, we generate four gene-knockout mice based on high-resolution structures targeting distinct DMT components: two intermediate filament-like tektins (TEKT1, TEKT5) and two enzymes (TSSK6, DUSP21). The depletion of TEKT1, shared by sperm flagella and motile cilia, causes male infertility characterized by impaired sperm motility and loss of the tektin bundle, whereas sperm-specific Tekt5 knockout (KO) mice remain fertile with largely normal flagellar function, indicating functional divergence within the tektin family. Tssk6 KO spermatozoa exhibit severely disturbed morphology and motility, resulting in homozygote infertility and heterozygote subfertility. Phosphoproteomics reveals dysregulated phosphorylation of axonemal proteins, highlighting the critical role of kinase-mediated signaling in regulating sperm motility. Conversely, Dusp21 KO mice display no fertility or sperm motility defects, suggesting compensatory phosphatase activity. Phenotypic comparisons between Tekt1 and Tssk6 KO mice suggest their involvement in distinct subtypes of asthenozoospermia. Overall, this study elucidates how filamentous and enzymatic DMT proteins govern sperm function through divergent mechanisms, which have implications for molecular diagnosis of male infertility.

PubMed: 41764189
DOI: 10.1038/s41467-026-69714-4

Experimental method

ELECTRON MICROSCOPY (3.7 Å)