Pathway Human Homo sapiens

Cilium Assembly

R-HSA-5617833 in Reactome release 97: under Organelle biogenesis and maintenance, with 233 genes placed in it by the mapping files and 2 child pathways in the hierarchy.

The same number in the other species

Reactome writes the mouse and rat events it infers from a human pathway under the human number with the species token. A door opens only where that species' own list in this release holds the id: R-MMU-5617833 (mouse), R-RNO-5617833 (rat). Whether the event was inferred from this one is what the record says.

The record
The genes
Parents and children

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This page reads the pathway's record from its source while you read the rest; with scripts off the card stays at its loading line. Reload with scripts on to see it, or open the source's own page from the link in the card.

01The record

Reactome's own record of this pathway

What this tells you

The pathway list, the hierarchy and the genes on this page are read from the files Reactome publishes for Reactome release 97, built into this site on 2026-09-09: the pathway list, the hierarchy relationship file and the two gene mapping files. The record card is the one live read, Reactome's own record of this pathway.

Reactome's download page describes the mapping files: Mapping files link the source database identifier to the lowest level pathway diagram or subset of the pathway, all levels of the pathway hierarchy or database identifier to all reactions. [R13] The gene list here is the all-levels mapping of NCBI Gene ids, filled from the all-levels mapping of Ensembl ids where the NCBI file has no row for a gene; each row names which file it came from by the shape of its source id. Each row carries the evidence codes the file writes for it, as written and unranked, and both where the file writes both; no page of Reactome's documentation the survey read defines the codes, so this page does not expand them. A gene id the identity files do not name is kept as the source's own id with no door rather than turned into a symbol.

On citing what a search finds, Reactome says: It should be remembered that while we strive to contain the most current and accurate data, Reactome should not be used in citations where other primary sources of information are available. [R12] The record card prints the literature Reactome attaches to a curated pathway for that reason. The data are public domain: All data in the Reactome database and files derived from that data are licensed under the Creative Commons Public Domain Dedication (CC0). User may copy, modify, and distribute these data, even for commercial purposes, without asking for permission. Attribution is encouraged but not required. [R10] The pathway illustrations are licensed apart, under CC BY 4.0, and none is shown here.

A gene on this list is one Reactome places in this pathway in this release, and that is all the row says: it does not say the gene is expressed in a tissue or associated with a disease, which are the other two explorers' questions, read from other sources. Reactome's papers of record are [R01] [R02].

[R01] Ragueneau E, Gong C, Sinquin P, Sevilla C, Beavers D, Grentner A, et al. (2026). The Reactome Knowledgebase 2026. Nucleic Acids Research 54:D673-D681. PMID 41251150, doi 10.1093/nar/gkaf1223.
[R02] Milacic M, Beavers D, Conley P, Gong C, Gillespie M, Griss J, et al. (2024). The Reactome Pathway Knowledgebase 2024. Nucleic Acids Research 52:D672-D678. PMID 37941124, doi 10.1093/nar/gkad1025.
[R10] Reactome, reactome.org. License Agreement. https://reactome.org/license, read 2026-09-09.
[R12] Reactome, reactome.org. Citing us. https://reactome.org/cite, read 2026-09-09.
[R13] Reactome, reactome.org. Download. https://reactome.org/download-data, read 2026-09-09.

Stable id: R-HSA-5617833.8
Class: Pathway
Species: Homo sapiens (human)
Inferred: no: a curated human pathway
Disease pathway: no
Released: 2014-12-11
Last updated: 2023-06-07
Events inside: 2, counted from the record

Cilia are membrane-covered organelles that extend from the surface of eukaryotic cells. Cilia may be motile, such as respiratory cilia) or non-motile (such as the primary cilium) and are distinguished by the structure of their microtubule-based axonemes. The axoneme consists of nine peripheral doublet microtubules, and in the case of many motile cilia, may also contain a pair of central single microtubules. These are referred to as 9+0 or 9+2 axonemes, respectively. Relative to their non-motile counterparts, motile cilia also contain additional structures that contribute to motion, including inner and outer dynein arms, radial spokes and nexin links. Four main types of cilia have been identified in humans: 9+2 motile (such as respiratory cilia), 9+0 motile (nodal cilia), 9+2 non-motile (kinocilium of hair cells) and 9+0 non-motile (primary cilium and photoreceptor cells) (reviewed in Fliegauf et al, 2007).

Cilium biogenesis involves the anchoring of the basal body, a centriole-derived organelle, near the plasma membrane and the subsequent polymerization of the microtubule-based axoneme and extension of the plasma membrane (reviewed in Ishikawa and Marshall, 2011; Reiter et al, 2012). Although the ciliary membrane is continuous with the plasma membrane, the protein and lipid content of the cilium and the ciliary membrane are distinct from those of the bulk cytoplasm and plasma membrane (reviewed in Emmer et al, 2010; Rohatgi and Snell, 2010). This specialized compartment is established and maintained during cilium biogenesis by the formation of a ciliary transition zone, a proteinaceous structure that, with the transition fibres, anchors the basal body to the plasma membrane and acts as a ciliary pore to limit free diffusion from the cytosol to the cilium (reviewed in Nachury et al, 2010; Reiter et al, 2012). Ciliary components are targeted from the secretory system to the ciliary base and subsequently transported to the ciliary tip, where extension of the axoneme occurs, by a motor-driven process called intraflagellar transport (IFT). Anterograde transport of cargo from the ciliary base to the tip of the cilium requires kinesin-2 type motors, while the dynein-2 motor is required for retrograde transport back to the ciliary base. In addition, both anterograde and retrograde transport depend on the IFT complex, a multiprotein assembly consisting of two subcomplexes, IFT A and IFT B.

The importance of the cilium in signaling and cell biology is highlighted by the wide range of defects and disorders, collectively known as ciliopathies, that arise as the result of mutations in genes encoding components of the ciliary machinery (reviewed in Goetz and Anderson, 2010; Madhivanan and Aguilar, 2014).

Literature Reactome attaches

When cilia go bad: cilia defects and ciliopathiesNat. Rev. Mol. Cell Biol., 2007, vol. 8, p. 880-93PubMed 17955020
Ciliogenesis: building the cell's antennaNat. Rev. Mol. Cell Biol., 2011, vol. 12, p. 222-34PubMed 21427764
The base of the cilium: roles for transition fibres and the transition zone in ciliary formation, maintenance and compartmentalizationEMBO Rep., 2012, vol. 13, p. 608-18PubMed 22653444
Molecular mechanisms of protein and lipid targeting to ciliary membranesJ. Cell. Sci., 2010, vol. 123, p. 529-36PubMed 20145001
The ciliary membraneCurr. Opin. Cell Biol., 2010, vol. 22, p. 541-6PubMed 20399632
Trafficking to the ciliary membrane: how to get across the periciliary diffusion barrier?Annu. Rev. Cell Dev. Biol., 2010, vol. 26, p. 59-87PubMed 19575670
Intraflagellar transport complex structure and cargo interactionsCilia, 2013, vol. 2, p. 10PubMed 23945166

Reactome's record lists 14 orthologous events, R-MMU-5617833 (Mus musculus), R-RNO-5617833 (Rattus norvegicus) among the species this site serves, and 12 in species this site opens no page for.

Reactome ContentService, this pathway's record · Reactome v97 · read 2026-10-01 ET · Reactome pathway browser"Cilium Assembly". Reactome, release 97, https://reactome.org/PathwayBrowser/#/R-HSA-5617833 with StableID: R-HSA-5617833.8 (accessed 2026-10-01 ET). Reactome version 97 (CC0).

Reading this pathway's record from Reactome (the pathway record).Still reading. A first read of a pathway can take a while; this page waits up to 35 seconds for it, and its scripts then bring in the panel, or a line saying what did not arrive.

02The genes

Genes Reactome places in this human pathway

The mapping files place 233 genes in this human pathway; showing 101 to 200, in pages of 100, sorted by symbol for reading. The order carries no ranking.

Genes Reactome places in this human pathway, page 2 of 3
Gene	Authority id	Mapping file id	Evidence codes
GeneGRHL1	AuthorityHGNC:17923	Mapping file id29841 NCBI file	EvidenceTAS
GeneGRHL2	AuthorityHGNC:2799	Mapping file id79977 NCBI file	EvidenceTAS
GeneGRHL3	AuthorityHGNC:25839	Mapping file id57822 NCBI file	EvidenceTAS
GeneHAUS1	AuthorityHGNC:25174	Mapping file id115106 NCBI file	EvidenceTAS
GeneHAUS2	AuthorityHGNC:25530	Mapping file id55142 NCBI file	EvidenceTAS
GeneHAUS3	AuthorityHGNC:28719	Mapping file id79441 NCBI file	EvidenceTAS
GeneHAUS4	AuthorityHGNC:20163	Mapping file id54930 NCBI file	EvidenceTAS
GeneHAUS5	AuthorityHGNC:29130	Mapping file id23354 NCBI file	EvidenceTAS
GeneHAUS6	AuthorityHGNC:25948	Mapping file id54801 NCBI file	EvidenceTAS
GeneHAUS7	AuthorityHGNC:32979	Mapping file id55559 NCBI file	EvidenceTAS
GeneHAUS8	AuthorityHGNC:30532	Mapping file id93323 NCBI file	EvidenceTAS
GeneHDAC6	AuthorityHGNC:14064	Mapping file id10013 NCBI file	EvidenceTAS
GeneHSP90AA1	AuthorityHGNC:5253	Mapping file id3320 NCBI file	EvidenceTAS
GeneIFT122	AuthorityHGNC:13556	Mapping file id55764 NCBI file	EvidenceTAS
GeneIFT140	AuthorityHGNC:29077	Mapping file id9742 NCBI file	EvidenceTAS
GeneIFT172	AuthorityHGNC:30391	Mapping file id26160 NCBI file	EvidenceIEA, TAS
GeneIFT20	AuthorityHGNC:30989	Mapping file id90410 NCBI file	EvidenceIEA, TAS
GeneIFT22	AuthorityHGNC:21895	Mapping file id64792 NCBI file	EvidenceIEA, TAS
GeneIFT25	AuthorityHGNC:25019	Mapping file id51668 NCBI file	EvidenceIEA, TAS
GeneIFT27	AuthorityHGNC:18626	Mapping file id11020 NCBI file	EvidenceIEA, TAS
GeneIFT38	AuthorityHGNC:19009	Mapping file id23059 NCBI file	EvidenceIEA, TAS
GeneIFT43	AuthorityHGNC:29669	Mapping file id112752 NCBI file	EvidenceTAS
GeneIFT46	AuthorityHGNC:26146	Mapping file id56912 NCBI file	EvidenceIEA, TAS
GeneIFT52	AuthorityHGNC:15901	Mapping file id51098 NCBI file	EvidenceIEA, TAS
GeneIFT54	AuthorityHGNC:17861	Mapping file id26146 NCBI file	EvidenceIEA, TAS
GeneIFT56	AuthorityHGNC:21882	Mapping file id79989 NCBI file	EvidenceIEA, TAS
GeneIFT57	AuthorityHGNC:17367	Mapping file id55081 NCBI file	EvidenceIEA, TAS
GeneIFT70A	AuthorityHGNC:25853	Mapping file id92104 NCBI file	EvidenceIEA, TAS
GeneIFT70B	AuthorityHGNC:26425	Mapping file id150737 NCBI file	EvidenceIEA, TAS
GeneIFT74	AuthorityHGNC:21424	Mapping file id80173 NCBI file	EvidenceIEA, TAS
GeneIFT80	AuthorityHGNC:29262	Mapping file id57560 NCBI file	EvidenceIEA, TAS
GeneIFT81	AuthorityHGNC:14313	Mapping file id28981 NCBI file	EvidenceIEA, TAS
GeneIFT88	AuthorityHGNC:20606	Mapping file id8100 NCBI file	EvidenceIEA, TAS
GeneINPP5E	AuthorityHGNC:21474	Mapping file id56623 NCBI file	EvidenceTAS
GeneIQCB1	AuthorityHGNC:28949	Mapping file id9657 NCBI file	EvidenceTAS
GeneKIF17	AuthorityHGNC:19167	Mapping file id57576 NCBI file	EvidenceTAS
GeneKIF24	AuthorityHGNC:19916	Mapping file id347240 NCBI file	EvidenceTAS
GeneKIF3A	AuthorityHGNC:6319	Mapping file id11127 NCBI file	EvidenceTAS
GeneKIF3B	AuthorityHGNC:6320	Mapping file id9371 NCBI file	EvidenceTAS
GeneKIF3C	AuthorityHGNC:6321	Mapping file id3797 NCBI file	EvidenceTAS
GeneKIFAP3	AuthorityHGNC:17060	Mapping file id22920 NCBI file	EvidenceTAS
GeneLZTFL1	AuthorityHGNC:6741	Mapping file id54585 NCBI file	EvidenceTAS
GeneMAPRE1	AuthorityHGNC:6890	Mapping file id22919 NCBI file	EvidenceTAS
GeneMARK4	AuthorityHGNC:13538	Mapping file id57787 NCBI file	EvidenceTAS
GeneMCHR1	AuthorityHGNC:4479	Mapping file id2847 NCBI file	EvidenceTAS
GeneMCIDAS	AuthorityHGNC:40050	Mapping file id345643 NCBI file	EvidenceIEA, TAS
GeneMIR34B	AuthorityHGNC:31636	Mapping file idENSG00000207811 Ensembl file	EvidenceTAS
GeneMIR34C	AuthorityHGNC:31637	Mapping file idENSG00000207562 Ensembl file	EvidenceTAS
GeneMIR449A	AuthorityHGNC:27645	Mapping file idENSG00000198983 Ensembl file	EvidenceTAS
GeneMIR449B	AuthorityHGNC:32794	Mapping file idENSG00000207728 Ensembl file	EvidenceTAS
GeneMIR449C	AuthorityHGNC:37302	Mapping file idENSG00000251856 Ensembl file	EvidenceTAS
GeneMKKS	AuthorityHGNC:7108	Mapping file id8195 NCBI file	EvidenceTAS
GeneMKS1	AuthorityHGNC:7121	Mapping file id54903 NCBI file	EvidenceTAS
GeneMOV10	AuthorityHGNC:7200	Mapping file id4343 NCBI file	EvidenceTAS
GeneMYB	AuthorityHGNC:7545	Mapping file id4602 NCBI file	EvidenceTAS
GeneNDE1	AuthorityHGNC:17619	Mapping file id54820 NCBI file	EvidenceTAS
GeneNEDD1	AuthorityHGNC:7723	Mapping file id121441 NCBI file	EvidenceTAS
GeneNEK2	AuthorityHGNC:7745	Mapping file id4751 NCBI file	EvidenceTAS
GeneNINL	AuthorityHGNC:29163	Mapping file id22981 NCBI file	EvidenceTAS
GeneNOTCH1	AuthorityHGNC:7881	Mapping file id4851 NCBI file	EvidenceTAS
GeneNPHP1	AuthorityHGNC:7905	Mapping file id4867 NCBI file	EvidenceTAS
GeneNPHP3	AuthorityHGNC:7907	Mapping file id27031 NCBI file	EvidenceTAS
GeneNPHP4	AuthorityHGNC:19104	Mapping file id261734 NCBI file	EvidenceTAS
GeneODF2	AuthorityHGNC:8114	Mapping file id4957 NCBI file	EvidenceTAS
GeneOFD1	AuthorityHGNC:2567	Mapping file id8481 NCBI file	EvidenceTAS
GenePAFAH1B1	AuthorityHGNC:8574	Mapping file id5048 NCBI file	EvidenceTAS
GenePCM1	AuthorityHGNC:8727	Mapping file id5108 NCBI file	EvidenceTAS
GenePCNT	AuthorityHGNC:16068	Mapping file id5116 NCBI file	EvidenceTAS
GenePDE6D	AuthorityHGNC:8788	Mapping file id5147 NCBI file	EvidenceTAS
GenePKD1	AuthorityHGNC:9008	Mapping file id5310 NCBI file	EvidenceIEA, TAS
GenePKD2	AuthorityHGNC:9009	Mapping file id5311 NCBI file	EvidenceIEA, TAS
GenePLK1	AuthorityHGNC:9077	Mapping file id5347 NCBI file	EvidenceTAS
GenePLK4	AuthorityHGNC:11397	Mapping file id10733 NCBI file	EvidenceTAS
GenePPP2R1A	AuthorityHGNC:9302	Mapping file id5518 NCBI file	EvidenceTAS
GenePRKACA	AuthorityHGNC:9380	Mapping file id5566 NCBI file	EvidenceTAS
GenePRKAR2B	AuthorityHGNC:9392	Mapping file id5577 NCBI file	EvidenceTAS
GeneRAB11A	AuthorityHGNC:9760	Mapping file id8766 NCBI file	EvidenceTAS
GeneRAB11FIP3	AuthorityHGNC:17224	Mapping file id9727 NCBI file	EvidenceTAS
GeneRAB3IP	AuthorityHGNC:16508	Mapping file id117177 NCBI file	EvidenceTAS
GeneRAB8A	AuthorityHGNC:7007	Mapping file id4218 NCBI file	EvidenceTAS
GeneRFX2	AuthorityHGNC:9983	Mapping file id5990 NCBI file	EvidenceTAS
GeneRFX3	AuthorityHGNC:9984	Mapping file id5991 NCBI file	EvidenceTAS
GeneRHO	AuthorityHGNC:10012	Mapping file id6010 NCBI file	EvidenceIEA, TAS
GeneRP2	AuthorityHGNC:10274	Mapping file id6102 NCBI file	EvidenceTAS
GeneRPGRIP1L	AuthorityHGNC:29168	Mapping file id23322 NCBI file	EvidenceTAS
GeneSCLT1	AuthorityHGNC:26406	Mapping file id132320 NCBI file	EvidenceTAS
GeneSDCCAG8	AuthorityHGNC:10671	Mapping file id10806 NCBI file	EvidenceTAS
GeneSEPTIN2	AuthorityHGNC:7729	Mapping file id4735 NCBI file	EvidenceTAS
GeneSFI1	AuthorityHGNC:29064	Mapping file id9814 NCBI file	EvidenceTAS
GeneSMO	AuthorityHGNC:11119	Mapping file id6608 NCBI file	EvidenceTAS
GeneSSNA1	AuthorityHGNC:11321	Mapping file id8636 NCBI file	EvidenceTAS
GeneSSTR3	AuthorityHGNC:11332	Mapping file id6753 NCBI file	EvidenceTAS
GeneTCP1	AuthorityHGNC:11655	Mapping file id6950 NCBI file	EvidenceTAS
GeneTCTN1	AuthorityHGNC:26113	Mapping file id79600 NCBI file	EvidenceTAS
GeneTCTN2	AuthorityHGNC:25774	Mapping file id79867 NCBI file	EvidenceTAS
GeneTCTN3	AuthorityHGNC:24519	Mapping file id26123 NCBI file	EvidenceTAS
GeneTFDP1	AuthorityHGNC:11749	Mapping file id7027 NCBI file	EvidenceIEA, TAS
GeneTMEM216	AuthorityHGNC:25018	Mapping file id51259 NCBI file	EvidenceTAS
GeneTMEM67	AuthorityHGNC:28396	Mapping file id91147 NCBI file	EvidenceTAS
GeneTNPO1	AuthorityHGNC:6401	Mapping file id3842 NCBI file	EvidenceTAS

Evidence codes on this page: IEA, TAS, as the mapping file writes them; a row carrying two was written twice by the file, once under each. The mapping file id says which file placed the gene: an NCBI Gene id from NCBI2Reactome_All_Levels.txt, an Ensembl gene id from Ensembl2Reactome_All_Levels.txt. The two files can disagree about a code, so a row's codes are the one file's view. Measured by this site's build over this release on 2026-09-09: of the 138,908 human pathway-gene pairs both files place, 207 (0.149 per cent, over 47 genes) carry TAS in the Ensembl file where the NCBI rows carry IEA alone.

Reactome mapping files, the human rows for this pathway · Reactome release 97 · read 2026-09-09 · Reactome downloads"NCBI2Reactome_All_Levels.txt" and "Ensembl2Reactome_All_Levels.txt", Reactome, release 97, https://reactome.org/download-data/ (date of access 2026-09-09). Data CC0; attribution encouraged.

03The hierarchy

Parents and children in this release's hierarchy

Parents

Organelle biogenesis and maintenanceR-HSA-1852241330 genes

Children

Reactome's hierarchy is a graph rather than a tree: a pathway can sit under more than one parent, and the gene counts are each pathway's own placements at every level under it, so a parent's count is not the sum of its children's.

Reactome, the human pathway list and hierarchy relationship file · Reactome release 97 · read 2026-09-09 · Reactome downloads"ReactomePathways.txt" and "ReactomePathwaysRelation.txt", Reactome, release 97, https://reactome.org/download-data/ (date of access 2026-09-09). Data CC0; attribution encouraged.