axonemal nexin link

GO:0005931 · Cytoskeleton · Multiprotein complex · Proposed

A protein complex in ciliary and flagellar axonemes that interconnects neighboring outer doublet microtubules. [GO:0005931]

Synonyms: axonemal interdoublet link; nexin-dynein regulatory complex; N-DRC

Part of: axoneme (GO:0005930)

UniProt location names: UniProt Consortium, CC BY 4.0. Reference label and route sources.

Components

Component	Type	Part of / acts on	Grounding	Genes	Stoichiometry	Essential	Role
axonemal nexin-link subunits	Protein	part of	Reviewed label only (reviewed name; no accession asserted)			UNKNOWN	Protein subunits that build the axonemal nexin-link complex. `GO:0005931` GO identifies the axonemal nexin link as a protein complex. `DOI:10.1073/pnas.1910960116` Gui et al. 2019 used Chlamydomonas N-DRC mutants and tagged subunits to localize scaffold and associated subunits in the axonemal nexin-dynein regulatory complex.

Taxonomic distribution

NCBITaxon:3055 Chlamydomonas reinhardtii — COMMON: Chlamydomonas flagellar axonemes carry axonemal nexin links that have been resolved by cryoelectron tomography. [DOI:10.1083/jcb.200908067]

Canonical examples

NCBITaxon:3055 Chlamydomonas reinhardtii — Green-algal model whose wild-type and N-DRC mutant flagellar axonemes were compared by cryoelectron tomography. [DOI:10.1083/jcb.200908067]

Functions

regulation of cilium movement GO:0003352 — The Chlamydomonas axonemal nexin link connects neighboring outer doublets and forms part of the dynein-regulatory network that coordinates flagellar beating.
- DOI:10.1083/jcb.200908067 Heuser et al. 2009 identified the dynein regulatory complex as the axonemal nexin link in Chlamydomonas.
- DOI:10.1073/pnas.1910960116 Gui et al. 2019 refined Chlamydomonas N-DRC subunit positions and connections to neighboring axonemal structures.

Mechanism graphs

The axonemal nexin link connects doublets (FUNCTION)

In Chlamydomonas flagella, N-DRC subunits form an axonemal nexin link that connects neighboring outer doublet microtubules and contributes to dynein regulation.

Subject	Predicate	Object	Evidence
axonemal nexin-link subunits	are part of	axonemal nexin link	`DOI:10.1073/pnas.1910960116` Gui et al. 2019 structurally localized scaffold and associated subunits within the Chlamydomonas N-DRC.
axonemal nexin link	links	outer doublet microtubules	`GO:0005931` GO defines the axonemal nexin link by its interconnections between axonemal outer doublets. `DOI:10.1083/jcb.200908067` Heuser et al. 2009 identified the Chlamydomonas dynein regulatory complex as the nexin link.
axonemal nexin link	participates in	regulation of cilium movement	`DOI:10.1083/jcb.200908067` Heuser et al. 2009 described the DRC/nexin link as a regulatory node in cilia and flagella. `DOI:10.1073/pnas.1910960116` Gui et al. 2019 analyzed N-DRC structural connections implicated in flagellar beat regulation.

Discussions

CURATION_TODO (OPEN): Resolve exact source-neutral groundings for the full 11-or-more-member axonemal N-DRC subunit cohort. GO exactly identifies the axonemal nexin link as a protein complex, but this curation pass did not verify exact InterPro, Pfam or other source-neutral accessions for the complete 11-or-more-member Chlamydomonas N-DRC subunit set or its conserved ortholog groups.

Evidence

GO:0005931 Gene Ontology cellular-component term for the axonemal nexin link.
GO:0005930 Gene Ontology places the axonemal nexin link within the axoneme.
DOI:10.1083/jcb.200908067 Heuser et al. 2009, 'The dynein regulatory complex is the nexin link and a major regulatory node in cilia and flagella', Journal of Cell Biology.
DOI:10.1073/pnas.1910960116 Gui et al. 2019, 'Scaffold subunits support associated subunit assembly in the Chlamydomonas ciliary nexin-dynein regulatory complex', PNAS.

Curation history

2026-09-23T11:14:29Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-23T11:15:38Z codex · EXPANDED_RECORD — Added axoneme parthood, N-DRC synonymy, a reviewed-label-only N-DRC subunit component, Chlamydomonas scope, cilium-movement regulation function, GO and DOI evidence, a nonmechanistic N-DRC graph, and a component-grounding TODO.
2026-09-23T11:16:02Z codex · REFINE_AXONEMAL_NEXIN_LINK_GRAPH — Changed the axonemal nexin-link graph edge from regulates to participates in so the structure points at the cilium-movement regulation process without regulating the regulation node itself.
2026-09-23T11:26:04Z codex · ADDRESSED_REVIEW — Resolved PR #1387 review issues #1388 and #1389 by renaming the graph title so it does not say GO:0005931 regulates doublets and broadening the subunit-grounding TODO to the complete 11-or-more-member N-DRC cohort.

Source: data/structures/cytoskeleton/axonemal_nexin_link.yaml