Affinage

TEKTIP1

Tektin bundle-interacting protein 1 · UniProt A6NCJ1

Round 2 corrected
Length
209 aa
Mass
24.2 kDa
Annotated
2026-04-28
7 papers in source corpus 2 papers cited in narrative 3 extracted findings

Mechanistic narrative

Synthesis pass · prose summary of the discoveries below

TEKTIP1 is a microtubule inner protein (MIP) that occupies the center of the tektin bundle within doublet microtubules of cilia and flagella, where it stabilizes bundle architecture by preferentially binding TEKT3 and facilitating TEKT3's association with other tektin family members (PMID:34715025, PMID:38448737). Loss of TEKTIP1 in mice causes disorganized axoneme ultrastructure, reduced sperm motility, and male subfertility, establishing it as essential for proper flagellar function (PMID:38448737).

Mechanistic history

Synthesis pass · year-by-year structured walk · 2 steps
  1. 2021 High

    Cryo-EM of the 48-nm repeat of mammalian doublet microtubules revealed TEKTIP1 as a previously uncharacterized MIP positioned at the center of the tektin bundle, establishing its structural niche within the axoneme.

    Evidence Cryo-EM atomic model reconstruction of bovine respiratory cilia doublet microtubules

    PMID:34715025

    Open questions at the time
    • No functional data existed at this stage to determine whether TEKTIP1 is required for tektin bundle integrity
    • Binding partners and interaction surfaces within the bundle were unresolved
    • Role in motile versus primary cilia was not distinguished
  2. 2024 High

    Knockout of Tektip1 in mice demonstrated that the protein is required for axoneme organization and sperm motility, and that it stabilizes the tektin bundle through preferential interaction with TEKT3, bridging the structural observation to a physiological function.

    Evidence Tektip1-knockout mouse model with sperm motility assays, TEM of axoneme ultrastructure, and Co-IP of tektin family members

    PMID:38448737

    Open questions at the time
    • TEKTIP1–TEKT3 interaction relies on Co-IP without reciprocal pull-down or structural mapping of the interface
    • Whether TEKTIP1 functions equivalently in respiratory cilia versus sperm flagella is untested
    • Mechanism by which TEKTIP1 loss disrupts TEKT3 native status (degradation, misfolding, or mislocalization) is not resolved

Open questions

Synthesis pass · forward-looking unresolved questions
  • It remains unknown whether TEKTIP1 loss affects motile cilia beyond sperm flagella, what structural determinants mediate its selective binding to TEKT3, and whether TEKTIP1 mutations cause ciliopathies or male infertility in humans.
  • No high-resolution structure of the TEKTIP1–TEKT3 interface
  • No human genetic data linking TEKTIP1 variants to disease
  • Function in respiratory or other motile cilia not directly tested

Mechanism profile

Synthesis pass · controlled-vocabulary classification · explore literature graph →
Molecular activity
GO:0005198 structural molecule activity 2
Localization
GO:0005856 cytoskeleton 2 GO:0005929 cilium 2
Pathway
R-HSA-1852241 Organelle biogenesis and maintenance 2
Partners
TEKT3
Complex memberships
tektin bundle

Evidence

Reading pass · 3 per-paper findings extracted from the source corpus
Year Finding Method Journal Conf PMIDs
2021 TEKTIP1 was identified as a novel microtubule inner protein (MIP) located at the center of the tektin bundle within doublet microtubules (DMTs) of mammalian cilia, resolved by cryo-EM of the 48-nm repeat of bovine respiratory cilia DMTs. Cryo-electron microscopy (cryo-EM) atomic model reconstruction of mammalian doublet microtubules Cell High 34715025
2024 TEKTIP1 is required for male fertility and sperm motility in mice; Tektip1-knockout males are subfertile with reduced sperm motility and disorganized axoneme structures, demonstrating TEKTIP1's physiological role in stabilizing the tektin bundle and axoneme of sperm flagella. Tektip1-knockout mouse model, sperm motility assays, transmission electron microscopy of axoneme ultrastructure Cellular and molecular life sciences : CMLS High 38448737
2024 TEKTIP1 preferentially interacts with TEKT3 among tektin family members, and loss of TEKTIP1 disrupts the native status of TEKT3 and impairs TEKT3's interactions with other tektins, indicating TEKTIP1 stabilizes the tektin bundle through its interaction with TEKT3. Co-immunoprecipitation (Co-IP), loss-of-function analysis in Tektip1-/- mice, assessment of tektin bundle organization Cellular and molecular life sciences : CMLS Medium 38448737

Source papers

Stage 0 corpus · 7 papers · ranked by NIH iCite citations
Year Title Journal Citations PMID
2004 The DNA sequence and biology of human chromosome 19. Nature 271 15057824
2021 De novo identification of mammalian ciliary motility proteins using cryo-EM. Cell 111 34715025
2016 High-throughput analyses of hnRNP H1 dissects its multi-functional aspect. RNA biology 50 26760575
2022 NUDT21 limits CD19 levels through alternative mRNA polyadenylation in B cell acute lymphoblastic leukemia. Nature immunology 46 36138187
2022 Pro-prion, as a membrane adaptor protein for E3 ligase c-Cbl, facilitates the ubiquitination of IGF-1R, promoting melanoma metastasis. Cell reports 12 36543142
2023 DNA methylation abnormalities induced by advanced maternal age in villi prime a high-risk state for spontaneous abortion. Clinical epigenetics 11 36945044
2024 Tektin bundle interacting protein, TEKTIP1, functions to stabilize the tektin bundle and axoneme in mouse sperm flagella. Cellular and molecular life sciences : CMLS 10 38448737