Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2021 May 19:9:661350.
doi: 10.3389/fcell.2021.661350. eCollection 2021.

Intraflagellar Transport Proteins as Regulators of Primary Cilia Length

Wei Wang  1 , Brittany M Jack  1 , Henry H Wang  1 , Matthew A Kavanaugh  1 , Robin L Maser  2 , Pamela V Tran  1
Affiliations
Review

Intraflagellar Transport Proteins as Regulators of Primary Cilia Length

Wei Wang et al. Front Cell Dev Biol. .

Abstract

Primary cilia are small, antenna-like organelles that detect and transduce chemical and mechanical cues in the extracellular environment, regulating cell behavior and, in turn, tissue development and homeostasis. Primary cilia are assembled via intraflagellar transport (IFT), which traffics protein cargo bidirectionally along a microtubular axoneme. Ranging from 1 to 10 μm long, these organelles typically reach a characteristic length dependent on cell type, likely for optimum fulfillment of their specific roles. The importance of an optimal cilia length is underscored by the findings that perturbation of cilia length can be observed in a number of cilia-related diseases. Thus, elucidating mechanisms of cilia length regulation is important for understanding the pathobiology of ciliary diseases. Since cilia assembly/disassembly regulate cilia length, we review the roles of IFT in processes that affect cilia assembly/disassembly, including ciliary transport of structural and membrane proteins, ectocytosis, and tubulin posttranslational modification. Additionally, since the environment of a cell influences cilia length, we also review the various stimuli encountered by renal epithelia in healthy and diseased states that alter cilia length and IFT.

Keywords: IFT-A; IFT-B; cilia disassembly; ciliogenesis; ectocytosis; kidney; posttranslational modification.

PubMed Disclaimer

Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

FIGURE 1
FIGURE 1
The primary cilium and roles of IFT in cilium assembly/disassembly. Consisting of a 9 + 0 arrangement of a microtubular axoneme ensheathed by a specialized ciliary membrane, the primary cilium assembles initially within the cytoplasm at the modified centriole (1), which becomes the basal body that forms the base of the primary cilium at the plasma membrane. Extension and maintenance of the cilium, along with the entry and exit of structural and functional components and the BBSome, are mediated by IFT (2–4). Roles for IFT in ectocytosis (5) and cilia disassembly (6) have also been implicated (see text for details). The positive (+) and negative (–) ends of axonemal and cytoplasmic microtubules are indicated. The polycystins, PC1 and PC2, are localized at the ciliary membrane and are mutated in ADPKD.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Abdul-Majeed S., Nauli S. M. (2011). Dopamine receptor type 5 in the primary cilia has dual chemo- and mechano-sensory roles. Hypertension 58 325–331. 10.1161/hypertensionaha.111.172080 - DOI - PMC - PubMed
    1. Alazami A. M., Seidahmed M. Z., Alzahrani F., Mohammed A. O., Alkuraya F. S. (2014). Novel IFT122 mutation associated with impaired ciliogenesis and cranioectodermal dysplasia. Mol. Genet. Genomic Med. 2 103–106. 10.1002/mgg3.44 - DOI - PMC - PubMed
    1. Anvarian Z., Mykytyn K., Mukhopadhyay S., Pedersen L. B., Christensen S. T. (2019). Cellular signalling by primary cilia in development, organ function and disease. Nat. Rev. Nephrol. 15 199–219. 10.1038/s41581-019-0116-9 - DOI - PMC - PubMed
    1. Badano J. L., Mitsuma N., Beales P. L., Katsanis N. (2006). The ciliopathies: an emerging class of human genetic disorders. Annu. Rev. Genomics Hum. Genet. 7 125–148. 10.1146/annurev.genom.7.080505.115610 - DOI - PubMed
    1. Badgandi H. B., Hwang S. H., Shimada I. S., Loriot E., Mukhopadhyay S. (2017). Tubby family proteins are adapters for ciliary trafficking of integral membrane proteins. J. Cell Biol. 216 743–760. 10.1083/jcb.201607095 - DOI - PMC - PubMed

LinkOut - more resources