| Claim/annotation field | Organism/system | Key evidence (1-2 sentences) | Publication (first author, year, journal) | URL | Citation ID |
|---|---|---|---|---|---|
| Verified identity / family assignment | *Neurospora crassa*; conserved fungal/animal orthology | CIA30 was first described in *N. crassa* as a complex I intermediate-associated protein; later work identifies human NDUFAF1 as its ortholog, supporting annotation of UniProt O42636 as the fungal CIA30/NDUFAF1-family assembly factor rather than a catalytic complex I subunit. | Schiller, 2022, *Science Advances* | https://doi.org/10.1126/sciadv.add3855 | (pqac-00000021) |
| Primary molecular function | *N. crassa* | CIA30 is a transient complex I assembly factor/chaperone, not a mature holoenzyme subunit. In *N. crassa* it associates with the large membrane-arm assembly intermediate and is released during assembly progression. | Schulte, 2001, *Journal of Bioenergetics and Biomembranes* | https://doi.org/10.1023/a:1010730919074 | (pqac-00000028) |
| Biological process | *N. crassa* | Complex I assembly proceeds modularly, with peripheral and membrane arms formed separately; CIA30 participates specifically in membrane-arm biogenesis by associating with the large membrane-arm intermediate. | Schulte, 2001, *Journal of Bioenergetics and Biomembranes* | https://doi.org/10.1023/a:1010730919074 | (pqac-00000028) |
| Subcellular localization | *N. crassa* | CIA30 has an N-terminal mitochondrial import sequence of 12 amino acids, supporting mitochondrial localization consistent with its role in respiratory complex I biogenesis. | Schulte, 2001, *Journal of Bioenergetics and Biomembranes* | https://doi.org/10.1023/a:1010730919074 | (pqac-00000028) |
| Sub-mitochondrial localization / topology inference | Human ortholog; relevant conserved inference for fungal CIA30 | Human CIA30/NDUFAF1 is imported into the mitochondrial matrix and associates with inner-membrane assembly intermediates. This strongly supports annotation of fungal CIA30 as a matrix-side assembly factor acting on the inner membrane arm during assembly. | Dunning, 2007, *The EMBO Journal* | https://doi.org/10.1038/sj.emboj.7601748 | (pqac-00000025, pqac-00000026) |
| Complex/intermediate association | *N. crassa* | The large membrane-arm intermediate contains five mitochondrially encoded and six nuclear-encoded complex I subunits plus CIA30 and CIA84; CIA30 is absent from mature complex I. | Schulte, 2001, *Journal of Bioenergetics and Biomembranes* | https://doi.org/10.1023/a:1010730919074 | (pqac-00000028) |
| Intermediate size / composition | *N. crassa* | Disruption of a 21.3 kDa complex I subunit caused accumulation of ~350 kDa and ~200 kDa membrane intermediates; the ~350 kDa species contains multiple mtDNA-encoded subunits, at least six nuclear-encoded subunits, and CIA30/CIA84. | Dunning, 2007, *The EMBO Journal* | https://doi.org/10.1038/sj.emboj.7601748 | (pqac-00000030) |
| Bound versus free assembly-factor pools | *N. crassa* | In wild type, CIA proteins exist in roughly equal bound and free pools. Blocking small membrane-arm assembly shifts CIA proteins toward the bound pool, whereas failure to form a stable large intermediate leaves CIA proteins exclusively free. | Schulte, 2001, *Journal of Bioenergetics and Biomembranes* | https://doi.org/10.1023/a:1010730919074 | (pqac-00000029) |
| Specificity of effect | *N. crassa* | Characterization of cia mutants indicates that complex I is the only respiratory complex detectably affected; no other respiratory target was identified in the cited study. | Schulte, 2001, *Journal of Bioenergetics and Biomembranes* | https://doi.org/10.1023/a:1010730919074 | (pqac-00000029) |
| Role in mature enzyme vs assembly | *N. crassa* | CIA30 and CIA84 bind independently to the ~350 kDa assembly intermediate but do not interact with fully assembled complex I, supporting a chaperone/assembly-factor role rather than a structural role in the final enzyme. | Dunning, 2007, *The EMBO Journal* | https://doi.org/10.1038/sj.emboj.7601748 | (pqac-00000030) |
| Gene disruption / phenotype when disrupted | *N. crassa* and family-level inference | Deletion/disruption of CIA genes in *N. crassa* severely disrupts complex I assembly, motivating their use as candidate assembly-factor genes in other organisms. This supports annotation of cia30 as essential for efficient complex I biogenesis. | Janssen, 2002, *Human Genetics* | https://doi.org/10.1007/s00439-001-0673-3 | (pqac-00000017) |
| Conserved assembly pathway role | Yeast (*Yarrowia lipolytica*) | Cryo-EM shows NDUFAF1-dependent assembly starts from an early PP-module “seed” containing ND2, NDUFC2, NDUFAF1 and fungal CIA84; a later PP intermediate contains all 12 PP-module subunits. This refines functional annotation of fungal CIA30 as an early PP/membrane-arm assembly factor. | Schiller, 2022, *Science Advances* | https://doi.org/10.1126/sciadv.add3855 | (pqac-00000012, pqac-00000020) |
| Mechanism: conformational control | Yeast (*Yarrowia lipolytica*) | NDUFAF1/CIA30 locks the central ND3 subunit in an assembly-competent conformation and binds the ND3 TMH1–2 loop, preventing premature rearrangements during PP-module maturation. | Schiller, 2022, *Science Advances* | https://doi.org/10.1126/sciadv.add3855 | (pqac-00000012) |
| Mechanism: protective binding of ND3 loop | Yeast (*Yarrowia lipolytica*) | At 3.2 Å resolution, NDUFAF1 is seen to sequester the ND3 TMH1–2 loop and shield its conserved cysteine in a binding cleft, implying a protective role during assembly before later module joining. | Laube, 2024, *Acta Crystallographica D* | https://doi.org/10.1107/S205979832400086X | (pqac-00000008, pqac-00000018, pqac-00000022, pqac-00000024) |
| Quantitative structural data | Yeast (*Yarrowia lipolytica*) | NDUFAF1-associated early and late PP intermediates were resolved as ~170 kDa and ~280 kDa complexes at 3.2 Å resolution, providing direct structural support for transient assembly-factor association. | Laube, 2024, *Acta Crystallographica D* | https://doi.org/10.1107/S205979832400086X | (pqac-00000018, pqac-00000022) |
| Quantitative disruption phenotype | Yeast (*Yarrowia lipolytica*) | Deletion of NDUFAF1 reduced complex I content to ~14% of control and abolished detectable ubiquinone reductase activity, demonstrating that CIA30-family proteins are essential assembly factors rather than accessory stabilizers. | Schiller, 2022, *Science Advances* | https://doi.org/10.1126/sciadv.add3855 | (pqac-00000012, pqac-00000015) |
| Conserved partner proteins / pathway context | Mammalian MCIA complex | NDUFAF1 is part of the mitochondrial complex I intermediate assembly (MCIA) complex with ECSIT and ACAD9, with additional peripheral membrane components; this places CIA30-family proteins in a conserved assembly network for the membrane/PP arm. | McGregor, 2023, *Nature Communications* | https://doi.org/10.1038/s41467-023-43865-0 | (pqac-00000011, pqac-00000019) |
| Conserved mechanistic partner insight | Mammalian MCIA complex | ECSIT binding remodels ACAD9 and triggers FAD release, converting ACAD9 from a fatty-acid oxidation enzyme into a complex I assembly factor. Although CIA30 itself is not catalytic, this explains the mechanistic context of the NDUFAF1-containing MCIA pathway. | McGregor, 2023, *Nature Communications* | https://doi.org/10.1038/s41467-023-43865-0 | (pqac-00000011, pqac-00000019) |
| Interaction landscape in vertebrates | Human | CIA30/NDUFAF1 associates with newly translated mtDNA-encoded ND1, ND2 and ND3 and with many nuclear-encoded complex I subunits; it co-migrates with B460 and B830 kDa assembly intermediates but not with late-assembling NDUFS5. | Dunning, 2007, *The EMBO Journal* | https://doi.org/10.1038/sj.emboj.7601748 | (pqac-00000025) |
| Quantitative intermediate sizes in vertebrates | Human | CIA30-containing complexes were observed at ~440–500 and 600–700 kDa in one study, with related reports placing them at 500–850 kDa; these detergent-sensitive assemblies are consistent with transient association with assembly intermediates rather than the mature holoenzyme. | Dunning, 2007, *The EMBO Journal* | https://doi.org/10.1038/sj.emboj.7601748 | (pqac-00000025) |
| Pathway terminology / module definitions | Eukaryotic complex I, general | Authoritative structural work defines the N module for NADH oxidation, the Q module for ubiquinone reduction, and the proximal/distal P modules (PP/PD) for proton pumping. CIA30/NDUFAF1 acts in PP-module assembly, which maps well onto earlier “membrane-arm intermediate” terminology from *N. crassa*. | Schiller, 2022, *Science Advances* | https://doi.org/10.1126/sciadv.add3855 | (pqac-00000021) |
| Link to membrane lipid remodeling | Yeast (*Yarrowia lipolytica*) | Tafazzin, the cardiolipin-remodeling enzyme, was unexpectedly found as an integral component of the early NDUFAF1/CIA30-containing PP seed complex, linking complex I assembly to cardiolipin remodeling. | Schiller, 2022, *Science Advances* | https://doi.org/10.1126/sciadv.add3855 | (pqac-00000012, pqac-00000020) |


*Table: This table summarizes organism-specific evidence for Neurospora crassa CIA30 and conserved mechanistic insights from orthologous NDUFAF1/CIA30 studies. It is useful for functional annotation because it separates direct Neurospora findings from higher-confidence family-level inferences about localization, assembly intermediates, mechanism, and disruption phenotypes.*