PXD067693-1

PXD067693 is an original dataset announced via ProteomeXchange.

Title	Chaperonin TRiC bridges radial spokes for folding proteins locally translated in mammalian sperm flagella
Description	As animals evolved from external to internal fertilization, sperm flagella, which once transiently propelled sperm in water to reach nearby eggs, developed to beat for days or even longer within the female reproductive tract. How flagella were remodeled accordingly remains unclear. Unlike externally fertilizing zebrafish and sea urchin, mammalian sperm flagella feature a unique barrel-shaped bridge between axonemal radial spokes RS1 and RS2, though its components and function remain unknown. Here, using cryo-EM and cryo-ET combined with mass spectrometry and immunofluorescence staining, we reveal that this RS1-RS2 barrel (RRB) in mammalian sperm flagella is a group II chaperonin TRiC/CCT. We purified and resolved the unforeseen cryo-EM structure of TRiC from bovine sperm flagella, discovering that flagella TRiC contains the testis-specific CCT6B subunit. Additionally, we resolved the cryo-ET map of mouse sperm flagella RSs, containing the RRB, achieving local resolution of 10-14 Å. The in-situ RRB map displays two extra densities within its chambers in a polarized manner, suggesting the presence of folding substrates and a co-chaperone. In vivo cross-linking MS reveals diverse components interact with RRB TRiC before embedded into axoneme. Notably, mammalian flagella also contain components of translation machineries and actively synthesize proteins. Block TRiC ATPase activity abolishes sperm motility. Our results suggest that the RRB TRiC folds locally translated proteins to sustain mammalian flagella, providing new insights into flagellar remodeling in internally fertilizing species. Our findings also shed lights on male fertility and potential treatments for infertility.
HostingRepository	iProX
AnnounceDate	2025-08-12
AnnouncementXML	Submission_2025-08-25_02:14:38.290.xml
DigitalObjectIdentifier
ReviewLevel	Peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Unsupported dataset by repository
PrimarySubmitter	Nan Zhao
SpeciesList	scientific name: Bos taurus; NCBI TaxID: 9913;
ModificationList	No PTMs are included in the dataset
Instrument	Orbitrap Exploris 240

Revision	Datetime	Status	ChangeLog Entry
0	2025-08-25 02:14:18	ID requested
⏵ 1	2025-08-25 02:14:38	announced

Dataset with its publication pending

submitter keyword: TRiC, mammalian sperm flagella, cryo-EM

Lihua Zhang
contact affiliation	Dalian Institute of Chemical Physics
contact email	lihuazhang@dicp.ac.cn
lab head
Nan Zhao
contact affiliation	Dalian Institute of Chemical Physics
contact email	zhaonan@dicp.ac.cn
dataset submitter

iProX dataset URI