KMN network of the outer kinetochore in Drosophila melanogaster

The KMN network (Knl1, Mis12 complex and Ndc80 complex) is the core microtubule-binding module of the outer kinetochore. The Mis12 complex links the network to the centromere-proximal inner kinetochore; in Drosophila it binds the CENP-C homolog Cenp-C, because flies lack the CENP-T pathway. The Ndc80 complex binds spindle microtubules directly and forms load-bearing attachments. Knl1 (Spc105R in Drosophila) provides a scaffold for spindle assembly checkpoint proteins and for protein phosphatase 1. Drosophila has two Nnf1 paralogs, Nnf1a and Nnf1b, which form alternative Mis12 complexes.

MODULE:dmel_kmn_networkDRAFTCONCRETEProtein Complexmodules/dmel_kmn_network.yaml
outer kinetochoreGO:0000940
FB:FBgg0001871
FlyBase gene group KMN: Kmn protein network supercomplex
FlyBase release FB2026_03 groups 8 D. melanogaster genes as kmn protein network supercomplex (KMN); this module models that group.
GO:0000940
outer kinetochore
GO term grounding the module as outer kinetochore.

FlyBase lists Ndc80, Nuf2 and Spc25 in the Ndc80 complex group. The microtubule binding function is placed on the Ndc80 complex as a whole. Checkpoint proteins recruited by Spc105R (Bub1, BubR1, Bub3) and the RZZ complex (dmel_rzz_complex) are outside the module. FlyBase groups realized by this module: KMN (FBgg0001871). Subgroups folded into it: MIS12B, MIS12A, NDC80C, KNL1. Participants were generated from the FlyBase gene-group membership and mapped to UniProtKB by projects/FLYBASE_GENE_GROUPS/generate_modules.py from module_specs/dmel_kmn_network.yaml. None of the member genes has a gene review in this repository yet.

6Nodes
3Parts
1Variant Sets
2Variants
4Annotons
2Connections

Derived QC

Recommended-field compliance

100.0% recommended fields populated

All recommended fields populated.

Module deep research

✗ none found

No MODULE:dmel_kmn_network deep-research report alongside the module YAML.

Leaf nodes lacking representative members

✓ every leaf node grounds to a representative protein.

Template conformance

✓ every declared conforms_to bundle matches its template motif.

Function consistency and core coverage

0 gene-function check(s) reflected in core functions · 0 conflict(s) · 0 evidence or coverage gap(s) (1 comparison(s))

Retained noncore functions are reported separately; they do not require promotion to core functions. Support from representative genes does not establish conservation across the whole family. Missing reviews or identifiers leave a claim unverified.

AnnotonParticipantFunctionAssessment
ndc80_complex_complex PROTEIN_COMPLEX
Gene 		microtubule binding
GO:0008017 		Participant Unchecked
No direct UniProt participant to compare. Abstract selectors and complex-wide activities cannot be inferred from donor or subunit gene reviews.

Gene-review completeness (0/8 grounded genes reviewed)

0 complete review(s) · 0 with deep research · 8 missing review · 0 reviewed but lacking deep research

Gene Review Complete Deep research
Nnf1a A1ZBV9 ✗ — —
Spc105R M9PIC9 ✗ — —
Nnf1b Q8IPW3 ✗ — —
Spc25 Q9V3V7 ✗ — —
Nuf2 Q9VM45 ✗ — —
Mis12 Q9VS01 ✗ — —
Ndc80 Q9VYB1 ✗ — —
Kmn1 Q9VYX4 ✗ — —

Details

Context
Drosophila melanogasterNCBITaxon:7227
kinetochoreGO:0000776
KMN networkProtein Complexdmel_kmn_network

Spc105R (Knl1), Mis12 and Ndc80 complexes that form the microtubule-attachment core of the outer kinetochore.

outer kinetochoreGO:0000940
Context
Drosophila melanogasterNCBITaxon:7227
kinetochoreGO:0000776

Connections

mis12_complex -> ndc80_complex Positively Regulates
The Mis12 complex recruits the Ndc80 complex to the kinetochore.
mis12_complex -> knl1 Positively Regulates
The Mis12 complex recruits Spc105R/Knl1 to the kinetochore.
Part 1: checkpoint scaffold
Knl1 (Spc105R)Protein Complexknl1

Annotons

Spc105R Knl1 (Spc105R)
knl1_spc105r
Participant: Gene Product: Spc105R
Gene Product:
Spc105RUniProtKB:M9PIC9
Part 2: inner-kinetochore linker
Mis12 complexProtein Complexmis12_complex
Variant set: Nnf1a or Nnf1b Mis12 complex (One Or More)
Mis12 complex Nnf1a variantProtein Complexmis12_nnf1a

Annotons

Mis12 complex Nnf1a variant
mis12_nnf1a_complex
Participant: Protein Complex: Mis12 complex Nnf1a variant
Protein Complex:
Mis12 complex Nnf1a variantGO:0000444
Active units:
Kmn1
Participant: Gene Product: Kmn1
Gene Product:
Kmn1UniProtKB:Q9VYX4
Mis12
Participant: Gene Product: Mis12
Gene Product:
Mis12UniProtKB:Q9VS01
Nnf1a
Participant: Gene Product: Nnf1a
Gene Product:
Nnf1aUniProtKB:A1ZBV9
Mis12 complex Nnf1b variantProtein Complexmis12_nnf1b

Annotons

Mis12 complex Nnf1b variant
mis12_nnf1b_complex
Participant: Protein Complex: Mis12 complex Nnf1b variant
Protein Complex:
Mis12 complex Nnf1b variantGO:0000444
Active units:
Kmn1
Participant: Gene Product: Kmn1
Gene Product:
Kmn1UniProtKB:Q9VYX4
Mis12
Participant: Gene Product: Mis12
Gene Product:
Mis12UniProtKB:Q9VS01
Nnf1b
Participant: Gene Product: Nnf1b
Gene Product:
Nnf1bUniProtKB:Q8IPW3
Part 3: microtubule attachment
Ndc80 complexProtein Complexndc80_complex

Annotons

Ndc80 complex
ndc80_complex_complex
Participant: Protein Complex: Ndc80 complex
Protein Complex:
Ndc80 complexGO:0031262
Active units:
Ndc80
Participant: Gene Product: Ndc80
Gene Product:
Ndc80UniProtKB:Q9VYB1
Nuf2
Participant: Gene Product: Nuf2
Gene Product:
Nuf2UniProtKB:Q9VM45
Spc25
Participant: Gene Product: Spc25
Gene Product:
Spc25UniProtKB:Q9V3V7

Function

microtubule bindingGO:0008017